JPH01119327A - Apparatus for electrochemically controlling contamination of solid - Google Patents

Abstract

PURPOSE: To efficiently change the properties of a gaseous stream compsn. by providing the device with a porous solid state electrolyte forming the inside of a cell, a gas passageway, two electronically conductive regions and an electrode connecting member and arranging both regions in electrically opposing parts. CONSTITUTION: The surface of a ceramic body 15 of the cell 11 and the outside surface 11 of the cell are coated with the porous solid state electrolyte, such as Y2 O3 stabilized CrO2 , and the gas to be treated, such as NOx-contg. gas, is introduced from a fluid feeding path 14. The cell 10 executes an electrochemical treatment of reducing NOx, etc., by mounting to an electrode connector 21 and an opposing electrode connector or by energizing current an electrode conductor 25. Both electronically conductive regions 18 are interrupted by a region 23 having no electronic conductivity.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a solid electrochemical gas composition adjustment assembly, and in particular to vehicle exhaust, industrial exhaust such as mines and refineries, and fossil fuel pulverization plants. A novel air pollution control scrubber for removing sulfur oxides and nitrogen oxides from fluid streams such as flue gas, tail gas, industrial boilers, glass furnaces, natural gas-powered compressors, and exhaust gas from catalytic cracking regeneration towers. Regarding the assembly.

SUMMARY OF THE INVENTION The present invention provides an electrochemical fluid composition conditioning device or scrubber for modifying or removing gaseous or condensed phase components of a fluid stream, the device comprising a small or large surface area. consisting of porous, high surface area ceramic cells having an outer surface, a high surface area porous interior through which the fluid flow passes, and further having opposing ends forming the ends of the flow channels. It's very refreshing. At least two electrically conductive regions are located in electronically opposing portions of the cell (
segment). A first electrode connection is provided electronically insulated from the electrically opposing portion, and the first opposing electrode connection is in contact with an electronically conductive region of the cell. It is installed in the part where A sealing member is disposed at each end of the cell in a fluid-tight relationship with the end of the entire cell to form a continuous fluid path into and from the cell and/or between multiple or partitioned cells. Each sealing member has a distal end that mates with the distal end of the cell and forms a continuous, fluid-tight passageway through a device such as a vehicle exhaust pipe, flue, or the like.

Detailed Description of Preferred Embodiments> Upstream side sealing member 1 at one end, illustrating FIG.
2 and at the other end are placed in fluid-tight engagement with a downstream sealing member 13, together forming a comprehensive fluid inlet passage 14 commencing with a seal inlet 26;
A total pollution control device or scrubber assembly 10 is shown comprising an electrochemical scrubber cell 11.

Sealing between these major parts is critical in many applications, and the annular shoulder 19 facing the annular collar 29 (this is better shown in Figure 2)
reinforced by a compression fit between the The cell 10 is suitable for direct current, alternating current or other waveform current energization by attachment to an electrode connector 21 and a counter electrode connector or by attachment as shown below terminating in an electrode lead 25. The outer cell surface 11 is covered with a thin porous layer 18 of conductive material, which layer is interrupted by the absence of conductors to form regions 23t- of no electronic conductivity. Located within this area is an electrode connector 21 electrically connected to an electrode conductor 24 .

FIG. 2 shows one embodiment of the mating portion that forms the basic seal between seals 12 and 130 enclosing the electrochemical cell therebetween. Inside the cell 11 is a ceramic body 15
Consists of. The surface of the cell is covered with a coating 18 of conductive material and an inner coating 20 of electronically conductive material.

In this embodiment, the cell is shown in construction with female conical sealing-fit receiving hubs 16 at opposite ends thereof. Located within and extending from the conductive coating 18 is the insulated electrode connector 21'ft contained therein, in place of the conductive surface area 230 of FIG. Figure 3 is another embodiment of the connector shown. The interior of the cell defining the fluid passage portion 17 of the entire flow path 14 is covered with a conductive inner coating 20 .

Separated from the outer metallization 20 is an electrode connector 22;
This is electrode conductor wire 25! physically connected. Electrode lead wire 25 is shown communicating with the outside of fluid flow path 14 by pulling out electrode hole 24a and exiting to the outside of the device. If the cell is adjacent to the outer end, the electrode leads can also pass through the entire fluid flow path and outlet at the outer end of the device.

The conical structure shown in FIG. 2 in mating relationship with the seals 12 and 13 surrounding the cell is first set and then on each end of the cell around the outer periphery of each end seal. A fluid-tight engagement is achieved by providing a shoulder portion 19 K that is structured in contact with the opposing collar ring 29. The internal engagement of the mating hub portions 16 and 16g of the cell with the male conical ends 28 and 28a of the sealing member is not critical in some cases or when non-axial movement is not important. Fluid leakage due to the lack of a fluid-tight fit can be bridged by the outer annular hub and shoulders 29 and 19.

Figure 3 shows a jL egg-shaped ball-socket type cell hub 1.
6 and 16g are shown, the dirt mates with the sealed ends 28 and 28g of the socket and is easily assembled to provide a substantially airtight engagement. Electrode connector 21 is shown insulated from the conductive coating of the cell by placing it on the bare portion.

FIG. 4 is an exploded view that best illustrates the preferred conical end embodiment of the cell. During assembly, the end hubs are connected to end units 12 and 1.
30 into a predetermined position with the opposing member. Annular collar 2
It is necessary to use a low to moderate pressure m between the seal collar 29 and the shoulder ring 19, which is simply a contacting seal end face 27g overlaid by 9. A force ζ-limited passage is not necessary, although a restricted seal inlet pipe 26 is shown in this figure. The ends 12 and 13 fit oppositely into the structure of the cell hubs 16 and 16g, and the peripheral collar 2
Consisting of a mating insert with 9. Sealing member 12
and 13' ft through the fluid path is thus defined by the smaller interior of piping 27 and internal piping is therefore unnecessary. During assembly of the cell, the terminal hub 28 seats in the spaced apart portions of the terminal units 12 and 13 with a locking friction fit. (No hub is shown in unit 12).

As is clear from the figure, a small to medium compressive force is applied to the cell 1.
It must exist between the shoulder ring 19 of No. 1 and the annular seal collar 29. Although restricted inlet piping 26 is depicted in end units 12 and 13, such restricted piping is not required. Ends 12 and 13 are cell hub 1
It may simply consist of a fluid-tight open structure with a mating hub insert 28 that fits oppositely into the structures 6 and 16α. The fluid path through the sealing members 12 and 13 is defined by the inside of the piping surface 27 of the sealing member when the restrained piping 26 is removed.

FIG. 5 shows an end view of upstream end seal 12 having an optional collar 29 around its periphery configured to contact shoulder 19 of FIG. FIG. 6 is an end view of the cell 11. When assembled, the shoulder 19 contacts the collar of the seal unit 12, while the fluid passage 17 communicates with the fluid passage 14 of the end seal. An electrode connector 22 is placed on the inner conductive surface 20 (not shown in FIG. 6), while a counter electrode connector 21
Connected to outer conductive surface 18.

FIG. 7 is yet another alternative mating structure in which a graduated oval shape is used in place of the exemplary socket indentation of FIG. 3 or a conical shape as shown in FIGS. 2 and 3. Additionally, shoulder 19 is shown as a female variant, but this is only a matter of convenience; the element could be reversed.

A cell 111 in the form of a large surface area, porous, solid sintered core is depicted in FIG. Cell 111 is porous core 40
, which forms a large surface channel through which the electrolyte passes.

The interior of the core 40 is homogeneous, and the exterior wall 41 is non-porous or glazed to make the cell peripherally fluid-tight and from the passageway 14 to the porous end hubs 42 and 42 of the cell.
Provides a restricted fluid flow leading to g. electronic conduction band 4
3 and 44 are provided via separate platings of conductive metal, such as silver, on the outside surfaces of the cell and are connected by electrical leads 44 to a voltage source. Also in the flow path through the electrolyte core 40 are nine opposed electrical leads 45 connected to a voltage source 46 .

FIG. 9 is a cross-sectional view of cell 111 taken along approximately 9-9 of FIG. The porous sintered core 40 is coated with a fluid-tight electrolytically conductive layer 41. Within the electronically conductive core, an electrical connector 44 is connected to a voltage source 46 .

FIG. 10 shows another embodiment of a sintered solid core cell 211 in which a large surface area core 40 is enclosed in exhaust flow piping 50. The core 40 is positioned within the piping 50 with spacer struts 51 within the piping 50 that allow the incoming gas flow 14 to pass through the core and exit along the axially porous surface of the core and exit the exhaust flow piping. into or through the flue channel 56 as well as the outlet of the discharge end 53 of the core. The ceramic structure as a whole is ionically conductive.

The child conduction band (strip) has 46ft of nine opposing wires electrically fixed to it, which is connected to a voltage source.

FIG. 11 shows a cell 21 cut along approximately 11-11 in FIG.
1 best illustrates the porous core that is positioned within the exhaust piping 50 by spacer struts 51 and forming fluid channels 56 between the core surface and the exhaust flow piping 50. Electrical connectors 45 connect the electronically conductive core and the voltage source to create an ionically conductive cell in operation.

The above-mentioned convention can be used directly, for example, in the exhaust system of a vehicle or an internal combustion engine, and equally applicable in the form of a chimney or the like in large-scale industrial and flue gas treatment installations. Upon conversion of the oxides of gases, e.g. flue or exhaust gases, to the less toxic or non-toxic corresponding elemental gases, oxyhydrides, oxides or hydrides, they become solid and can be safely discharged without collection; Alternatively, it can be captured and therefore not released into the environment. Since nitrogen oxides can be reduced to nitrogen gas according to the invention, it is harmless and can be freely released into the atmosphere. However, in the treatment of large quantities of flue gas, vertical cooling of the flue gas through a scrubber and co-collection equipment is required.
It is desirable to provide a collection device with a bag or sediment (eal cooling). Alternatively, the elemental sulfur produced in the present invention can be captured as a liquid - and cooled to a solid, eg, an ingot.

If desired, rather than converting a fluid stream component such as nitrogen oxides to nitrogen gas, the conversion may be performed by adding hydrogen to produce a hydride or oxyhydride such as ammonia, and the resulting compound may be converted to nitrogen gas as known to those skilled in the art. It may be collected during the process. Alternatively, the thus generated reduced at, such as ammonia, can be catalytically or non-catalytically
It is also possible to further remove toxic or undesirable species from the gas stream by reacting with substances such as ow or SOx.

The electrochemical cell L of the invention consists of a porous, high surface area, solid electrolyte, preferably a porous, high surface area, solid metal oxide electrolyte such as yttria-stabilized zirconia.

A large number of solid metal oxides can be used as electrolytes in the practice of this invention. Suitable oxides include, but are not limited to, zirconia (Zde02), hafnia CH1
0), titania CT(0,), lanthanide C1anth
anidaa) e.g. Seria (CsOl), Salaria C
8 Town 03>, Ittoria CYtOs), Elvia CEr
zO@), Scandia (ScO2), Peropskiite CparovsJttaa), Pyrochlore Cpy
roahlorms λ calcia (CaO*), magnesia (CMyO), gadolinia (CGtbOs'), bismuth oxide (21stOn), etc., or a combination of one or more of the above oxides. Preferably, one or more metal salts may be included in the electrolyte. Particularly preferred metal salts are metal oxides, silicides, fluorides, carbides, borides or nitrides, provided that the oxidation state of the metal is 1 or greater, but not greater than 7. Typical salts include, but are not limited to, titanium diboride CTi1k), molybdenum disilicide CMo84z), chromium carbide CCrC), zirconium carbide (ZdeCχ magnesia CMrtO' with silicon carbide C34C), There are lanthanum aluminized (L%Om) and itria (y, on).

The preferred electrolyte is a stabilized solid oxide. Preferred stabilized solid oxides are yttria stabilized zirconia CYSZ), gadolinia stabilized ceria and erbia stabilized bismuth oxide. A particularly preferable electrolyte is 10W!
It is an ittria-stabilized zirconia containing % ittria gold. Further preferred stabilizing electrolytes include Erbia stabilized bismuth oxide, calcia stabilized zirconia containing 8-12 wt% calcia, and ceria stabilized with gadolinia and other lanthanides such as praseodymia and samaria.

The high surface area, porous, solid oxides of the present invention may include open cell foams, sintered packed beds, honeycombs having repeating polygonal shapes, provided that the polygons have three or more sides or are flat-sided. can be manufactured as open-cell tubes or shells), or as open-cell tubes or shells). 0.001 to 10
The oxide can be filled into a housing/g under pressure and sintered as a powder having a diameter of 1,000 microns, preferably 1.0 to 1,000 microns in diameter.

In a second embodiment, ittria-stabilized zirconia powder is blended with a hydrogen-bonded solid combustible organic binder in an isostatic press at room temperature and so,o,o.

Fill with pat. The use of balanced pressure avoids cracking or other damage to the ceramic. The cell is then fired at 1400° C. for 3 hours in post-air with gradual temperature increases. The temperature rise from room temperature to 600°C takes about 18 hours, then the temperature rises to 1400°C-1500°C for 3 to 4 hours, and then the temperature is maintained at 1400-1500°C for 1 to 4 hours, Preferably, substantially all sintering occurs during this time.

It is critical that the temperature be increased slowly over time to remove moisture and volatiles in a gentle and orderly manner, melting the binder and oxidatively removing the binder without damaging the loaded powder. .

Generally, the coarse oxide powder is mixed with 0.01 to 75 wt% of a metal-poor organic binder. Suitable organic binders include, but are not limited to,
Alcohols, carboxylic acids, preferably substances that are solid at room temperature, such as higher alkyl (fatty) alcohols, ethers and carboxylic acids, such as - by way of example, polyacrylic acid, polyvinyl alcohol, stearic acid, nonadecanol, polyethylene oxide, etc.

In addition to the coarse oxide powder and organic binder, the solid oxide electrolyte contains up to 50 wIt% of fine oxide powder (b
itT%-odal) and may preferably further include up to 5 sot% of ceramic fines as a sintering aid.

Porous fillers such as polymeric beads or reducible, fusible, non-reactive metal beads such as zinc, iron, nickel, copper or silver beads create the desired pore size and distribution in the sintered cells. It is particularly preferred to include in order to obtain. Metal beads have the advantage of structural support until the sintering stage;
It is melted and removed during sintering, which is extremely important.

Alternatively, the powder may be plated with, for example, nickel or zinc, before sintering, and this plating is then removed in a chemical bath, such as dilute hydrochloric acid, or heated under an argon or hydrogen atmosphere to sublimate or melt the powder. I can do it. Additionally, the cells can be etched, for example in hydrofluoric acid or sulfuric acid, to remove undesirable substances such as silica and silicates or to improve the pore structure.

To avoid cracking due to thermally undistributed stresses (the hot cell is preferably placed in a thermal homogenizer; such a device has a much greater thermal conductivity than the cell, and therefore the temperature within the cell Stainless steel or Inconel, nickel/chromium/iron alloy pipe profiles have been found to work well.Alternatively, the cells can be fabricated with a metal mesh fabric (fab).
In addition, to reduce heat transfer due to radiation from the cell, it may be wrapped with insulating ceramic, paper or fibers such as commercially available alumina (140 g) or zirconia (ZrO,) fiber neutralization encapsulation. But it's okay.

A particularly preferred embodiment encapsulates the cells in one or more layers of metal mesh and further encapsulates the material in one or more layers of ceramic fibers. It is suitable that the ``two-layered'' object fits neatly at room temperature or in the heated section of a gas pipe. This unit can then be installed as a pipe section in an emissions control assembly. When using a compression seal, it is necessary to place a cushioning material, such as a rubber pad, in the line of force of the compression mechanism to avoid cracking due to sudden compression.

The cell of the present invention can be machined by attaching the cell to a rotating chuck on a mechanical lathe and using fixed tools. The 1-ball” seal depicted in the accompanying drawings is conveniently formed when the ball mill is mounted on a stationary chuck and an oil-based silicon carbide (Etc) grid is used to aid the machining process. It prevents undesirable heating and cracking. Care must be taken to avoid this.Using this method, mirror-like, vacuum-tight ceramic pieces can be routinely exposed.

Cells without (outer) walls can be developed by filling the powder mixture into appropriately sized tubes. Powder/binder/porous filler is next! Compact in a semi- or isostatic press. Preferred tubing materials are zirconium, graphite, and low metal content plastics.

Parts of the cell can be used for electrolytic or non-electrodepositable metal deposition using conductive materials that are safe at operating temperatures.
mralm-etrolmam) can be made electrically conductive by coating or plating. Iron, cobalt, nickel, copper, iron and platinum are preferred plating materials. The shoulders or rings at the ends of the cell can be worn away so that there is no direct electrical contact between the electronically conductive material on the inside and outside of the cell. Alternatively, the terminal ring may be removed prior to the plating step.

Plating is generally performed in a manner well known to those skilled in the art to form at least two separate electrodes on the cell.

- For boat fishing, the silver plating solution is prepared using the following multi-step method.

Bath solution A, which accounts for 64 to 1% of the final plating solution, is 5 (l
of silver nitrate dissolved in 2 tons of distilled, deionized water.

Solution B, which accounts for 32 SO1% of the final solution, is prepared by dissolving 2 L of distilled, deionized real F) 90 t of potassium hydroxide. Bath liquid C, which accounts for 2ν01% of the final solution, is 800
Add 809 sucrose to swj distilled or deionized water and add 1
00- 95% ethanol or boil the solution for 30 minutes.
Made by aging for 0 days. Solution D, also about 2ν of the final solution
0.1% is distilled or deionized water, which acts as a diluent.

Add concentrated aqueous ammonia solution dropwise to solution A until a dark precipitate forms. Approximately half of Solution B is then added, followed by concentrated aqueous ammonia dropwise until only a small amount of precipitate remains.

1. Add ammonium hydroxide dropwise to the remainder of solution B while stirring at the same time. Add slowly dropwise. At this point, all precipitate should just barely dissolve. This solution must be chilled in ice water at 0°C and used within 1 hour. Cool the solution in ice water at about 0°C and slowly add to solution A while stirring.

Next, solution C is also cooled in ice water at 0° C. and added to the mixture while stirring.

Place the cell at room temperature in a cooled (0° C.) plating container, pour the plating solution onto the ceramic cell in the container, and warm it to room temperature.

The solution is then heated to a slow boil. It is preferred to provide a slight vibration or agitation effect during plating.

It will be obvious to those skilled in the art that the proportions of solutions C and D can be varied to obtain the desired results and that the cells can be coated prior to plating to control the location of metal deposition on the ceramic cells. Dew. It will also be apparent to those skilled in the art that multiple layer plating is preferred to improve cell performance.

It is generally desirable to clean and cure the coating between multiple layers. During the deposition of one or more layers, annealing is preferably carried out at a temperature of 100 DEG to 500 DEG C. for a period of 5 to 60 minutes.

Similarly, a nickel plating solution suitable for use in the present invention can be prepared as follows. Solution A is 1 in 1 (8% C in l)
It is made by distilling and deionizing concentrated hydrochloric acid of 4 and 10 d/l.

Solution B contains 1, 0.5 f/PdCl, and 10 mt/
Prepare by dissolving 1 liter of concentrated hydrochloric acid in deionized water. Solution C is 4
5 f/l NiC4.6H, 0,509/l NH,
C1,100 f/t of sodium citrate and 0.5
It consists of a solution CI made from f/l ammonium hydroxide. Solution C1 consists of 4509/l sodium hypophosphite.

To plate the electrode area of the cell, the suitably coated cell is immersed in solution gA for 5 minutes, rinsed with distilled water, and immersed in solution B for 5 minutes. Solutions A and B are sensitizing baths. Thereafter, solution C2 at about 200-300 eC per 1 part of solution CI is added with stirring and the cell is immersed therein. Preferably solution C is cooled in ice water, the room temperature cell is immersed therein, the plating solution is warmed to room temperature, and plating is carried out as described above.

Additional metals or combinations of metals suitable for use in the present invention include, but are not limited to, platinum, rhodium, palladium, copper, iron, ruthenium, iridium, nickel/zinc, silver/platinum, Nickel/zinc/cobalt,
Examples include copper/zinc, copper/nickel/zinc, nickel/palladium, nickel/ruthenium, nickel/platinum, copper/iron, etc. - For example, when platinum is used as the plating metal, the following method can be used. Distilled water (0.5m
) with stirring are added aqueous methylamine (10 ml of 40%) and ammonium hexachloroplatinate (0.5 t). Add hydrated hydrazine (2.5 cc) with stirring,
Gently pump the liquid over and into the cell, keep the liquid at room temperature, and place a heat lamp over the cell to focus on the cell. Platinum is plated on the ceramic surface of the container wall, where the relative warmth of the cell is cold.

This is of critical importance when using expensive materials such as platinum, ruthenium, rhodium and palladium.

After the black/gray film has been deposited, the apparatus may be heated to a temperature of 70 DEG C.-100 DEG C. to plate off the remaining platinum. The cell is then rinsed with distilled water and heated at the glabella to a temperature of about 250°C for about 5 to 60 minutes.

The platinum/rhodium bath is prepared according to the method described above for the platinum bath, replacing up to 90% of the ammonium hexachloroplatinate with the appropriate concentration of rhodium trichloride.3H,O.

Ruthenium plating bath is ruthenium chloride (0,2f > f
t0D7? of hydrochloric acid and 1O- of distilled water. Methylamine (5mj of 40%) is added to this and the solution is allowed to stand for about 1 hour.

Hydrazine hydrate (0.5 cc) is then added to the stirred solution and the cell is then immersed therein for plating. During plating, the solution may be heated to a temperature of 70° to 100°C.

A porous sinter cell provides a high surface area reactor. The desired (high) surface area can also be achieved by extrusion of honeycombs or foams, preferably in the form of open cells.

Therefore, the desired surface area has a pore size of 0.1 to 1000 microns, preferably 10 to 10 microns per inch.
It can be obtained in zero pore, sintered packed beds, (preferably extruded) honeycombs, or open cell ceramic foams.

One of the challenges in providing solid electrolyte scrubbers or air pollution control devices is providing a seal that withstands operating conditions without loss of integrity. Therefore, depending on the application, the seal assembly may be a critical part of the invention.

It is critical that the sealing force ζ allows movement of the cell against thermal effects, vibrations, shocks and other operating conditions in which leakage can cause accidents. The present invention allows such movement to be carried out by “
It is provided with a sealing element and a cell in a "pol and socket" configuration. As is clear from the accompanying drawings, the cell ends can be conical, spherical or tapered, with a conical to spherical transition shape, and are suitable for the appropriate construction of the seal. A spherical embodiment is preferred.

An o-ring arrangement can conveniently act as an interface to the sealing surface along the line of compression.

It is often convenient to use a seal as an electrical connection to the cell. It is advantageous to use electrically conductive materials as all or part of the seal. Suitable materials include stainless steels such as Inconel alloys, ceramics such as silicon carbide, chromium carbide or suitable carbides, oxides, nitrides and borides, "cermets", gold/non-metal composites such as nickel/chromium/carbide. chrome, clad or 1
Faced forms include alumina or mullite covered with proprietary materials such as silver.

The preferred seal material is Inconel 601 stainless steel with a machine finish and nine faces arc plasma sprayed with electrically conductive cermet of the type used to protect turbine blades. Also preferred are silicon carbide and non-proprietary ceramics such as alumina, coprite or mullite.

The end seal optionally consists of a thin lubricant/sealant coated hardened surface of a material such as silver that acts as a lubricant at temperatures below 700-900°C or approximately 1500°C.
It can be a conductive ceramic such as silicon carbide or molybdenum carbide that can withstand temperatures above 2600°C, or it can be a conductive ceramic such as alumina (T440m), zirconium oxide (ZrOt), or doria (T440m) that can withstand temperatures below about 2600°C. It may be an oxide.

Current and harmful gases (i.e. NO) passing through the cell of the present invention.

The relationship between the removal of So, ) is as follows:
(tonic) is the ionic current, t(aLacro%
4c) is the electron current). The current measured is therefore the simultaneous sum of two independent currents, the ion electric cam and the background-independent or electronic current. Therefore, the practically effective current is calculated by the formula: % Formula %) and is expressed as i-(. or mA-mA.

According to Faraday's law, the harmful gas removal efficiency and t(iosi
The value of a) can be expressed: 1 (iosia) = u x [S#q]
day'a aosaiant (96,4892)
) and q is the number of equivalents per mole of gas converted or the number of electrons passed per molecule.

The +-q values for common gases are:

Gas +#q No 2 NO, 4 80, 4 N, 0 2 Q, 4 "H, 02 Generally this value will be 2 for each oxygen atom removed from or added to the molecule.

Since it is more convenient to use L/v+ais than who l / a a a, if we convert from me l / a a a using an approximation that regards the Faraday law expression as an ideal gas, we get the following equation: (RxTx60) where mA is the current in milliamperes due to the electrochemical removal of harmful gases by the cell of the invention; F is Faraday (constant) and P is the atmospheric pressure (units) as it enters the cell.
is the pressure of the gas flow at; 1000 is the factor for using mA; R is the gas constant of 0.082; ÷
-q is as defined above; T is the absolute temperature of the gas before entering the cell, 60 is the conversion factor of saC-4min, and t/min is the total flow rate of the gas flow entering the cell. and (gas) (gas concentration) is the mole fraction or likewise the volume fraction of the harmful gas in the total gas stream.

When the cell reaction beam is a gas, - is an electron, SZ is stabilized zirconium, and N, S, and O are nitrogen, sulfur, and oxygen, it is expressed by the following formula.

At the cell anode the reaction is: 4a +5
Ot(Q)=S(I)+20”-4g +2NO(I
F) = Nt (g) + 20" - At the cell anode the reaction is given by the following equation: 20" = 02 (y) + 4 m - The overall cell reaction is given by the equation: %Formula %() For example stabilized zirconia as electrolyte In the case of lead as the electrode, the cell reaction is:

In the examples, the pressure is 1 atm unless otherwise specified. Measurements were made using a digital multimeter. The voltage source was a Huwlett-Packard DC power supply in all cases.

The infrared spectra of the gas streams were measured with Fourier transform JR.

Cyclic coulometric measurements were determined with a Pine Instruments (CPina Isatrsmants) potentiostat.

Example 1 Itria stabilized zirconia tube (ZiZoro0) having a length of 2-3 inches, an outer diameter of 3 inches and an inner diameter of 3 inches
α.

5o1os, 0hio) with 472 Ittria stabilized zirconia powder (500-800 microns) and 39 (D
CHlC(Ce7fs)t-OH, 50,0001
Filled b/i- using an isostatic press. The filled cells were fired in air at 1400°C for 3 hr after the temperature was slowly increased to 1400°C using the temperature-time profile shown in Table I (where R, TJd was room temperature).

Table 1 Temperature Time (Ay) R, T, →60℃ 0.560℃→600
℃ 18.0600℃→1400℃
3.51400℃ 3.0 1400℃→R,T, 7.0 Gently and regularly remove moisture and volatile matter, melt the binder, and bond without damaging the filled ittria-stabilized zirconia powder. 600 to oxidize and remove the agent.
The gradual rise to ℃ is extremely negative.

Example 2 The cell of Example 1 was silver plated in the following manner. 4 fl of a plating solution was prepared as follows. Solution A, which accounts for 64 wj% of the final plating solution, contains 2 t of distilled, deionized and 550 t of silver nitrate. It was allowed to cleave to p4. Solution B, which accounts for 32 vol% of the final solution, is distilled at 2t,
Potassium hydroxide at 90F per deionized water was dissolved and cleaved. Solution C, which accounts for 2 voJ% of the final solution, is 80
0- distillation, deionization true 80? Add sucrose, 10
The solution was prepared by adding 100 m of 95% ethanol and 3.5 m of concentrated nitric acid and boiling the solution for 30 min. The liquid solution, which made up about 2vol% of the final solution, was distilled, deionized water that acted as a diluent.

Aqueous ammonium hydroxide (aqueous ammonia) was added dropwise to solution A until a dark precipitate formed. Approximately half of Solution B was then added. Concentrated ammonium hydroxide was then added until a small amount of precipitate remained. The remainder of Solution B was then added with stirring and simultaneous dropwise addition of ammonium hydroxide. The resulting solution was cooled to ice water at 0°C. The solution is then heated to 0℃
The mixture was cooled to ice water and slowly added to solution A while stirring. Solution C was also cooled to ice water at 0° C. and then added to the mixture with stirring.

A room temperature cell made according to the method of Example 1 and appropriately coated was prepared using MaatmrfLmm.
The peristaltic pump and the entire system have a diameter of Z" (with the exception of the top, where a siphon piping is used to allow air bubbles to exit from the top). It is cooled to 0°C with a vertical siphon. It was placed in a box container. The cell was sealed in place using a pneumatic ram. The plating solution was placed in a plating container using an lt separatory funnel, and was circulated around the cell to raise the temperature to room temperature. The solution was then slowly boiled and decirculated to approximately IA.

The solution is then removed from the container, the cell is rinsed with distilled, deionized water, and the coating is placed in a split-top furnace at 200°C for 72 hours.
hr annealed. The efficiency of the cell in removing nitric oxide (NO) from a gas stream containing 175 pptm No was calculated to be 92%.

Example 3 A nitric oxide (No ) stream containing 1000 ppm NO was applied to the plated cell of Example 2 at a rate of 0.58 L/ln/
The current in the cell was measured with a Digital Msltisatar at a gas flow rate of 450° C., a temperature of 450° C., and a voltage of 2.00 V. The results are summarized in Table 3.

Table Plate E-E, i-4, (Thirst A) Efficiency 0 〇
-0,2810,34% 0.481 1.0 13%0
．． 682 2.8 36%0.8
88 5.2 68%1.082
7.7 100% 1.281
7.1 92% 1.481
7.3 95% 1.681
7.1 92% 1.881
7.5 98% In the table above, E-Eo is the overvoltage (applied voltage above the open circuit potential with respect to the silver/air reference electrode). The above data shows the relationship between overvoltage, ion current and NO removal efficiency. Aging the cell in air at 500° C. for 10 days improves cell efficiency.

The relationship between NO removal efficiency from a flowing gas stream and overpotential at 450° C. and 1000 ppm NO is illustrated in FIG.

Example 4 An oxidizing flux containing 100 ppm NO was passed through the cell of Example 2 at a gas flow rate of 19 t/A and a temperature of 748°C, with the applied overvoltage varying from 0 to 1 volt. . Capacitive turnover ratio (VoLsmatric tsrso
*are eats (VTR)] is removal NO? −mol/
The unit of SSS/cell core cIIL is determined by least squares analysis to be a linear function with an appropriate constant overvoltage, and the R2 correlation coefficient is included in the data set. The data is shown in the light.

Table ■ E-E 6 i-4, (tnA)
n/AfXc1fL"O00 0,202-039810-' 0.39 3.8 74xlO-
'0.59 6.3 125xlF
'0.79 8.3 163X10
-'0.99 10.5 206xl
O-'s/MXcm"=210X 10-"X(E-E
6) -2,5
The method of Example 4 was followed. The results shown in Table IV were obtained.

Table ■ E-E6 i-i, (tmA)
s/MXcm"OO0 0,202,241x ] 0-' 0.40 4.5 89
xlO-'0.60 8゜4
163X10″0.80 10.6
211xlO-'1.00 1
2.2 238xlO-s/M
(:r!L" = 253 × 10-' (E A7 o
) 3-2 × 10-' : R''=0.993 Example 6 An IJ-stabilized zirconia cell with a silver/platinum porous electrode was molded according to the method of Examples 1 and 2 in air. It was aged at 500° C. for 10 days.

Equipotential measurements of ionic current and capacitive turnover rate were performed at three temperatures of 624°C, 706°C, and 748°C and 19°C, varying the NO content of the gas stream from 0 to 175 ppm.
t/m/cIIL! The gas flow rate was 1.91'
The overvoltage of is higher than that used in commercial equipment, where the water electrolysis potential has a practical limit of about 1 volt higher than the applied voltage. These N09 degrees correspond to some woodcutter combustion devices, such as natural gas fired boilers. Table V A.

According to the least squares method, the data shown for VE and VC showed that VTR was linearly related to the NO content of the gas.

Constants and correlations aR1 are given for each of the three temperatures.

Table VA-624℃ ppm Noi-46 (tlLA)
n7M xcm”25 0.7
14xlF'50 1.5
29xlU'-'75 2.1
41xlO"100 2.4
47xlO-61252,753xlO-
'150 2.9 58xlO
-'175 3.1 61x
lO=s/MXcm”=0.348 (9pvyh #
o)+7.4810″;R″=0.97 Table VB-706°C ppm NOi −i g (tnA) %/
M X c11L'0 0
Q25 0.7 1
4X10-'50 2.8
54xlO-'75 4.1
82xlO=100 5.0
97xlO-01256,3126xlO= 150 7.6 152xlU
-'175 g, 3 16
3xlO-'s /J/X1m"=0.98 Cppm
No)+0.017X10-';R2=0.
994 Table VC-748℃ ppm No i-4, (mA)
s/j/xcm”0 0
Q25 2.3 46
xlO””50 5.1 1
U1xlU-'75 5.7
114xlU-'100 6.7
132xlO-'125 7
．． 6 151xlO-1508, 5169xl
O-6 1759,0177xlO-'s/MXC1ll''=0.96 (ppm 7VO)+
27 X 10-;R''=0.96 Example 7゜Using the cell of Example 2, a fluid flow containing 1001000 pp was applied at a flow rate of 0.581/s/cm'' and 4 cc.
Cells were passed at °C. The actually measured capacitive turnover rate versus overvoltage is summarized in Table 3.

Table ■ A' E6 s s, (mA) s/Mxcm”OQ
Q O, 2980; 1 0.3xlO-'0.498 0
．． 8 3, OX 10-'0.698 1.8 7. O
x 1 o-'0.898 2.3 9.1xlF' 1.098 3.2 12.7x 10-"1.298
3.7 14.5X 10-6s/MxcrIL”=
12.5xl 04(A'-A',) -1,9x 1
0-”;R”=0.98 Example 8゜ Using the cell of Example 2, 1000 Tpm-No?
::”8 fluid flow with a flow rate of 0.58 L/m/α2 and 5
The cells were run at 00°C. The actually measured capacitive turnover rate vs. overvoltage is summarized in ①.

Table ■ E-E, (-j, (mA) s/
#xcm”0.274 0.7
2.7X10-'0.475 1.4
5.4X10-60.675 1
．． 9 7.6x10-'0.874
2.9 11.5X10-'1.074
4.1 16.0X10-'1
．． 275 4.6 18. IXI
U-'1.476 5.3 20
．． 9X10-'n/M Xm'-14,9X 10-'
(A'-E,)-1,lXl0';R''-0,99
4 Examples 9-15 Ittria-stabilized zirconia cells of the present invention were prepared according to the method of Examples 1 and 2 under varying conditions summarized in Table 1.

Table ■ 20 2 2 1500'C2 2162,51400"C3 22661400°C 1 23 9 2 1400"C4 24921400°C 1 2512 2 1400°C 3 2612 2 1400"C3 Example 16゜According to the methods of Examples 1 and 20, the following method Calcia stabilized zirconia powder (ZrO20,87M,
A calcia-stabilized zirconia cell was manufactured from Ca00.13M).

12 to 349.9211t of zirconium propoxide
2.5N concentrated nitric acid was added. In another container, dissolve calcium carbonate (13?) in concentrated nitric acid, and after the foaming has stopped, add water (5 cc)
) was added. The zirconium propoxide and calcium carbonate solutions were combined to obtain a clear reddish-brown solution. The bath solution was added to the aqueous ammonia solution with vigorous stirring, centrifuged, and the fluid was discarded. The solid was dissolved in 0.1M aqueous ammonia (2x
), dried at a temperature of 90° C. for 12 A and residual nitrates were separated off, and heated to approximately 1000° C. to convert the material into the oxide phase. The thus obtained calcia-stabilized zirconia powder was transferred to a calcia-stabilized zirconia tube (Alfa C
chemical) and sintered by the method of Example 1.

Example 17 According to the method of Examples 1 and 2, calcia-stabilized-zirconia-doped ceria (Zr.

CaO1, Q, 87Af; Cab, 0.13M) was prepared. Dissolve zirconium propoxide (3 tcc) with concentrated nitrogen [(I Qcf-)K. In another container, concentrate nitric acid (4 c.
Calcium carbonate (1,3f
), and cerium chloride heptahydrate (3,7Sl) was added thereto. The 2m solution was mixed to obtain a reddish-brown solution, which was added to a vigorously stirred aqueous ammonia solution and further processed according to the method of Example 16.

Example 18゜Calcia stabilized ceria powder (CaO2% 0.85M”
,Cab.

0,151. f ), 1! ! Carbonated calcium (1,5?) was dissolved in deionized water (70%) containing (5ffi#), and cerium chloride heptahydrate (31,62?) was dissolved in brown nitric acid.
f) and according to the method of Example 16, Example 16
Manufactured by the method.

Example 19゜Itria stabilized zirconia powder (ZrO2; 0.9
1 M:Y, 0. ．． 0.09M) was prepared by the method of Example 16 into a solution of zirconium propoxide (3a6ml), methanol (30j16) and a-nitrogen K (A3mg), and yttrium nitrate hexahydrate (3,45f) in deionized water ( 70 Mj) and concentrated nitric acid (511 ft). After the conversion of the powder to the oxide phase was complete, cells were made using the methods of Examples 1 and 2.

EXAMPLE 2 A calcia stabilized zirconia cell doped with 0° iron oxide was prepared by the method of Examples 1 and 2 from a light green powder made by the arrow method. Iron bath liquid &! Ferrous chloride (2-031
Concentrated hydrobromic acid/ethylene glycol C2:3CV/V
)]. Zirconium propoxide (
A concentrated nitric acid (122,514) solution of 349,92y) and a concentrated nitric acid solution of calcium carbonate (13f) were combined according to the method of Example 167, and a part of the combined bath solution was mixed with a ferrous chloride solution according to Table 2. added to.

Table ■ ((ZrOt)o, ay <Ca0)olsEl-2c
FsO)zz Number of moles of F-0 F# Bath solution volume (m) 0, UO252,4XlO-'
0.23530.0050 4.8X10-
' 0.47060.0100 9.
7X10-” 0.94610.0200
1.93X10-' 1.89200
．． 0400 3.86X10-' 3.
78400 0 0 (control)
Example 21° Chromium oxide doped calcia stabilized zirconia cells were made according to the methods of Examples 1 and 20 from chromium oxide doped calcia stabilized zirconia powder prepared in the following manner. Chromium metal powder (Z5 t Alfa
ProduataLot, No. 113078) was dissolved in concentrated hydrobromic acid (40% K) to make a solution. The solution was initially dark green. After stirring for 1 liter at room temperature, liquid bromine (51 Lt) was added and the solution was heated for an additional 2 hours with stirring. The final bath solution was dark red. Zirconium propoxide (349,9211Lt) in concentrated nitric acid (12Z51
) Bath solution and concentrated nitric acid #I solution of calcium carbonate (1:l) were combined according to the method of Example 16, and part of the combined solution &X
Added to the chromium solution according to the instructions.

Table X (CZr0t)o,av (CaO)o,ts)t
-zccrO]zE Number of moles of chromium Volume of chromium bath solution (d) 0.0001 Z32X10
-' 000230.0003 6,9
6X10-' o, o O690,01002,
32xlO-' 0.02320.0300
6.96X10-' 0.06960.
0100 2.32X10-' 0.2
3200 0 0 (Control) Example 2Z A silver/platinum electrode was formed by electroless plating of each layer of silver and platinum on the ittria-stabilized zirconia cell produced by the method of Example 1, and the resulting cell about 800℃
Baked for 1 hour. The cell was placed in a Ls%db-7g tube furnace at 1
Heated at 40°C. A flow of argon containing No was passed through the hot cell in an open circuit (no current). 21 of FT-IH
The outlet or outlet stream was checked using a g% Gengaku cell and no ammonia was detected. The cell was kept open and hydrogen was added to the gas, but again no ammonia could be detected. Connect the cell slightly to a DC power supply and connect the platinum/
The inside of the cell was held cathodically at approximately 2.4 V with respect to an air reference electrode. The FT-JR spectrum of the gas effluent from the cell showed that ammonia was synthesized.

Example 23 In the cell and method of Example 22 where water vapor is added instead of hydrogen, an FT-IB of the gas effluent from the cell showed that ammonia was being synthesized.

Using the cells and methods of Examples 24 and 22, N and Uik were used as alternative raw material gases for No K. A 1'' T-IR of the effluent gas from the cell showed that ammonia was being synthesized.

Example 25 Using the cell and method of Example 23, water vapor was added to the gas stream instead of hydrogen. FT-J of effluent gas from cell
The R spectrum showed that ammonia was synthesized.

As is clear from Example p) above, regardless of the type of nitrogen oxides contained in the feed stream and regardless of the use of cheap water vapor as a source of hydrogen scum or hydrogen atoms, the invention Ammonia can be generated. Thus, the present invention is not only effective in removing toxic or undesirable components from fluid streams, but is also effective in generating useful products, such as ammonia, by processing the fluid streams. . Likewise carbon particles or carbon-rich components of the fluid stream, such as CO.

It should be appreciated that some or all of the oxygen atoms in COt C, Hy Og can be replaced by hydrogen according to the present invention to create, for example, methane.

EXAMPLE 26 To independently confirm the electrochemical data, direct measurement of the Not and SO3 content of the waste stream passing through a cell of the invention before and after the fluid stream passes through the reactor or scrubber cell. Gas phase FT-IR measurements were performed. Initially, the reactor cell was bypassed and the room temperature gas stream was passed directly through the FT-IR original cell to determine the baseline spectrum. As a control, we conducted the gas flow into the hot reactor cell under open circuit conditions (no current flowing through the cell) and verified that there was no noticeable change in the Not or SO1 content due to catalytic, thermal or various effects. Ta. A DC voltage was then applied to the reactor with no other changes to the settings and the gaseous effluent was analyzed again and found to have a reduced No and/or SO, 6 degrees.

At an operating temperature of 400°C, measurements of gas phase IR spectra show that the cell of the invention reduces the No concentration by about 85-90% and the SO! It was shown that the concentration was reduced by 100%. 5
At an operating temperature of 0.000C, both gases in the effluent stream were reduced to virtually zero. None of the compounds were present at any concentration above the detection limit of Fourier transform IH using a gas cell with a length of 21 mm.

The following examples show reactor sizes for a variety of applications.

Example 27゜LOOMW Reactor size for natural gas boiler is input as follows ffL: 250pp Starvation NO: 450±50
°C flue gas temperature (before air preheater or economizer)
Calculated from fuel natural gas (approximately cHa@210KC1 mole) as follows. The overall chemical formula for the combustion process is c#, +20t+s -Co, +211. O+
It has an enthalpy of 8 to +21 OKC.

I MW-I for heat input IAfW (megawatts) K
X l O+”W =2.39 x 10-s calories/#-〇-1,14
5 moles of exhaust gas in moles of CH,/,,a 1il1112/##C-3,13
xlO-”v-le NO/aaa-0,188 mol N
O/Excuse calculation m l Z5 x 10-”cm” (side/Mx3”-
15X10-'@)Is') Therefore, for a boiler heat input of IMW, a reactor volume of approximately 12.5 L is required.

This is approximately 1.6 cII of 1 diameter flue gas piping.
This corresponds to the I thickness part. Therefore, 1.25 m' reactor is 10
Required for 0MW natural cast-iron boilers.

Example 28 The power required to operate the reactor of the present invention can be calculated as follows: P-VXA-C0,50,5)XA-(0,50,5)X(FX2X3.13X10-
”% LeNo/saa/IMW) -O-0.6KW/IMW Therefore, about 0-0.1% of the input thermal energy of the boiler
is estimated to be necessary for operation of the scrubber of the present invention. Competing technologies require at least 50 times more power.

EXAMPLE 29 The reactor or scrubber cell size of the present invention for a 25 MW natural gas turbine producing 500 ppm NO can be calculated as follows. Fitting the appropriate data as a function of temperature to a simple exponential equation, the 10
The activation energy corresponding to doubling of the Not removal rate per 0° C. is calculated as approximating 13-15 KC1 mole. 1750 reactor unit or scrubber assembly
When placed in or near the combustion zone of a natural gas-fired turbine with an apparent temperature of ℃.

The value of s/Af
tri6oxide) to the VTR (capacitive turnover rate) to the partial pressure (next cooling air power reduces this value to an apparent 500 ppm NO at the chimney), resulting in 1/s/s /cm", which is an order based only on the size of the VTR used.

Therefore, for a gas turbine heat input of IMW: 1 MW
-12.5 moles of exhaust gas/1#c-2,5X10-”
Mol No/age -1,50 Mol NO/mi% -1,5cy" (s/% X3' -1) Therefore,
From available data, the NOx output of a 25 MW natural gas-fired turbine requires approximately 150 cm” (9%
The reactor volume will be S). The energy consumption for this application, determined according to Example 28, approximates the boiler power consumption and is about 0-0.1% of the turbine heat input.

Returning to the explanation of the drawings, Figure 13 is a schematic diagram of the scale 3 showing the relationship between gases, electrolytes, and ``conductors'' at the molecular level.
It is in phase format. Nitrogen oxide molecules have a dipole moment and tend to orient the oxygen atoms in contact with the electrolyte.

Oriented oxidant gas molecules accept two electrons to form a kinetic intermediate. This species rearranges the oxygen atoms by dissolving them as O1 ions in the electrolyte and can therefore be compared to two electrons that are forced into the gas molecule by the electronic phase. The nitrogen atom then reacts with a second nitrogen atom to form gaseous N.

form. The dissolved O-2 ions move to the anode,
Therefore, those two electrons are returned to the electronic circuit (electrons move, but are always conserved). The oxygen atoms combine with second oxygen atoms to form gas phase O8. This process requires the physical juxtaposition (proximity) of all three phases at essentially the same moment in time.

FIG. 14 shows a molecular scale two-phase format using SO3 instead of No. The electrolyte phase is ceria-stabilized cadrinia (C-182Gd, 180.), and the region in contact with the gas phase is a mixed conductor, ie, both ionic (0-ffi) and electronic (monoconductive).

This means that the ring ratio is less than 1. This mixed conductor state is preferably achieved by changing the composition of the surface, such as by doping with iron, chromium, etc. 2
The phase format requires only air/solid contact, not the three-phase contact of the example shown in FIG. Figure 20 illustrates the electrochemical behavior of a two-phase material.

FIG. 15 is a graph of the cyclic voltamodrum of a calcia stabilized zirconia cell with flowing nitrogen gas flow or the same flow with 1% SO3 added. The horizontal axis is the voltage relative to the air/noble metal reference electrode and the vertical axis is the current through the cell.

Currents above the voltage @(0,0) correspond to the oxidation of SO1→SO8, while currents below the horizontal axis move in the opposite direction and correspond to the reduction of SQ, to S. ``The voltage line (ie, no current) and the curve cross at approximately the thermodynamic voltage expected for SO7.

The total flow rate of the waste flow is 2.4 t/mis, and the voltage sweep rate is 0.25 V/1 h. As is clear from the figure, the present invention not only deals with SO, but also selective oxidation or aging of harmful gases.

Figure 16 operates at 450°C. Figure 2 is a graphical representation of the practical performance of a cell of the present invention using silver/platinum electrodes and polished Inconel 601 end seals, showing the relationship between voltage and ionic current.

The vertical axis is the ion current, and the horizontal axis is the voltage. Gas passing through the cell is 247pp, 500pp or 745jl
Nitric oxide (NO) was added to argon.

The higher the voltage, the greater the current, ie, the greater the efficiency.

The current increased as a function of No content, ie the higher the No content, the higher the current.

FIG. 17 is a graph of the current/voltage relationship for a cell of the present invention operated with a 9-gas source gas, an yttria-stabilized zirconia electrolyte, and a silver/platinum electrode. Usually only use the first 0-3 volts. Gas flow rate is 0.501
．． /min.

Figure 18 shows N at 0.100 and 175 ppm at 748°C.
2 is a graph showing the voltage vs. ion current of an ittria-stabilized zirconia cell of the present invention with silver/metal electrodes operated with a gas flow having an o content.

FIG. 19 is a graph similar to FIG. 16 except that the horizontal axis is the pp groove number and the measurements were taken at 2Y on the - foot. Each of these three curves represents the temperature of the yttria-stabilized zirconia cell of Example 1 using silver/platinum electrodes at different temperatures ranging from 624°C to 748°C.
% of waste flow rate.

FIG. 20 is a cyclic portammogram of Example 2 101% chromium doped calcia stabilized zirconia cell. In this case, the cell is made of calcia-stabilized zirconia (0,2
5"i, d, The measured current must therefore travel between both the plug material and the calcia-stabilized zirconia material.The plug has both electronic and ionic current;
The fabric's calcia stabilized zirconia is only ionic current. Therefore, the electronic current is essentially "blocked" in the calcia-stabilized zirconia phase of the fabric, and the current measured is only due to ionic (gas redox-enhanced) activity. This configuration eliminates short-circuit phenomena. The two ceramic phases are nearly identical and have been deliberately chosen so that the thermal and other coefficients are as close as possible, otherwise processing of the ceramic and subsequent thermal cycling would be severely limited. The electrodes were porous electroless plated platinum and the cell was operated at a temperature of 850°C.

Each sweep of voltage increases the ionic current, which is caused by a reduction in the ring rate of the plug material, increasing the rate of gas oxidation and reduction per active area.

FIG. 22 illustrates transmittance (%T) versus wavenumber and shows the spectrum of thermally recombined N,0. This figure shows no current (
Figure 2 shows the spectrum of gas effluent from a hot cell (open circuit). The main absorption is N204 at about 1350 wavenumbers. The optical crossroad length of the IR measurement cell for this measurement was 51m! , and further exists ρ) is too short to indicate an unknown NO. ■
, and Ol have no absorption in the IR spectrum. N
,0. Note that the %T of is approximately 65%.

FIG. 23 is a sister diagram of FIG. 22, and shows when current is applied.

Hl 04 Long-term harmful gas flow components with no peaks are 10
0% removed? It's proven.

As is clear from the above discussion, increased speed of electrochemical processes at electrochemical interfaces in which the isoelectrolyte has a ring ratio of less than 1 can be achieved in several ways. ring rate (i.e.

The proportion of current that passes as ions can generally be reduced by processes or impurities that allow ionic conduction but not completely eliminated electronic conduction (mixed conduction). This means that at least a portion of the current is electronic in nature and the remaining current is predominantly or entirely ionic (ie oxide ion transfer).

The term “mixed conduction” (tnizad co
+%d劃=1-side OS)", 1 darkening 1 resolution (darkm
d electrolyte)”, darkening vL layer (
darkened electrolyte), 1 blackened tlv# quality (blackened electrolyte)
yte), 1F center (F-aantara)”, ga
localized electron
s)''', ''localized ho
lam)”, trapped electron (ala
ctros” and 1 trapped vacancy.
holes)” 1 compatible.

For example, as is clear from Examples 20 and 21, the -factor can be lowered by doping the crystal lattice with one or more atoms that induce the desired phenomenon. Preferred doping materials are transition metals such as niobium, iron, cobalt, nickel, titanium, tantalum, chromium, vanadium, and the like. These impurities should be present in a range of about 10 ppm to 10 ppm. Non-transition metals in amounts of 0.2 to 80 ppm can also be used. Examples of suitable non-transition metals include barium. The presence of barium oxide in the bismuth oxide is about 30 or more metal moles. Additionally, non-metallic metals can also be used. For example, fluoride or sulfur substitution of oxide ions in the lattice results in low ring rates.

Common elements of different valences (i.e. C in the CaO2 lattice,
The dopant can also be incorporated into the lattice during the manufacture of the ceramic or by various subsequent processes such as direct chemical reactions,
It can be added by electrochemical reaction, ion bombardment, etc.

Also shown in FIG. 17, dramatic increases in current (ie, increases in electrochemical reaction rates) are obtained at high voltages, particularly 2-10 volts and above. Applying relatively extreme voltages induces this phenomenon in many materials, including zirconia and ceria. Generally, the term ``extreme voltage'' refers to a voltage that is small but sufficient to initiate the decomposition (electrolysis) of the electrolyte; for stabilized zirconia, this is approximately 1.5 to 2.2
It is greater than 5 volts. For other thermodynamically more unstable materials, such as ceria phase or bismuth oxide, lower voltages are sufficient.

However, excessive voltages must be avoided. If the voltage is too high, the electrolysis of the electrolyte will proceed too quickly, creating 7 lac on the ceramic. Generally, depending on the particular ceramic dimensions and composition, temperature, gas phase environment, dalene size, surface area, and similar physicokinetic and thermodynamic parameters, voltages in excess of 10-20 volts are excessive.

The prior art (Maze%) is inferior to that of the present invention, with a small surface area, solid, non-porous electrolyte on the cathode surface of 1! Although the use of an electric field to provide a pressure-induced F-center has been disclosed, it has not been found to predict the critical factor to overcome the shortcomings of the Ha-port 1.

Similarly, a reduction in ring ratio can be achieved by the use of reactive gas vapors at elevated temperatures or pressures. For example, hydrogen gas at a temperature of 400° C. or higher can induce a decrease in ring ratio. In this case, it is necessary to pass IEa to increase the reaction rate! However, the use of reactive gases under applied voltage is preferred. The term "reactive gas" refers to a gas that reacts chemically, at least slightly, with the electrolyte under operating conditions.

The method described above for increasing the rate of electrochemical processes at the electrochemical interface of the solid state electrochemical cell of the present invention can be achieved by using one of the methods described above alone or in combination. See, for example, FIG. 20, which shows the values obtained using both voltage and dopant. The steady increase in current, noted as the large voltage that is repeatedly swept, is directly related to the increased speed of the electrochemical process.

In general, it is important to avoid a significant drop in ring ratio throughout the electrolyte body, as this can lead to short circuits between electrodes, resulting in wasted power. Therefore, the surface of the electrolyte is approximately 0.0
Although the electrolyte may have a very low annular ratio in the range of 0.001 to 0.9999, at least the blocking part of the electrolyte between the two electrodes (partition) needs to have a higher annular ratio. This higher ring ratio should be greater than or equal to about 0.50, preferably greater than or equal to about 0.90, and most preferably greater than 0.95.

The invention is designed to remove harmful components from fluid streams regardless of size, such as No. Provides an excellent reactor or scrubber cell that not only efficiently and economically removes N, 04, SO, etc., but also converts harmful components in the fluid stream into commercially useful substances such as ammonia, sulfur, and methane gas. It will be clear to those skilled in the art that this constitutes a key feature in this field, as it provides further means to do so.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the assembly and partial cross section of one embodiment of the scrubber of the present invention. FIG. 2 is an axial cutaway elevational view of one embodiment of a scrubber;
Figure 3 shows one embodiment of a central electrochemical cell anchored between sealed sections. FIG. 3 is an axial cross-sectional view of an assembly showing another embodiment of an activatable cell. FIG. 4 is an exploded perspective view of the assembly showing further aspects of the central electrochemical cell of the assembly. FIG. 5 is an end view of the seal member placed remotely on the assembled device. FIG. 6 is an end view of an activatable cell placed between the distal seal members of the scrubber assembly. FIG. 7 depicts a cross-sectional elevation view of a further embodiment of the activatable scrubber cell of the present invention. Figure 8 shows a large surface area, sintered core with linear continuous open pores.
FIG. 2 is an exploded perspective view of a ceramic cell. FIG. 9 is a cross-sectional view of FIG. 8 taken along line 9-9. FIG. 10 is a partially cutaway elevational view of another embodiment of a large surface area, (continuous) open pore solid core cell of the present invention. FIG. 11 is a cross-sectional view of FIG. 10 taken along line 11-11. FIG. 12 depicts an end view of an embodiment of the radiator of the present invention. FIG. 13 is a molecular scale three-phase format of the present invention. Figure 1441 is a molecular scale mixed conductor format of the present invention. FIG. 15 is a cyclic portammogram for removing sulfur dioxide by oxidation and sulfur dioxide using the calcia-stabilized zirconium cell of Example 16. FIG. 16 is a graph of voltage versus current for the yttria-stabilized zirconium cell of Example 2 with silver/platinum type electrodes plated thereon operated at 450° C. with varying concentrations of nitrogen oxide. Figure 17 shows that 5
2 is a graph of 1i current versus voltage for the cell of Example 2 operated at 00°C. Figure 18 is a graph of voltage versus ion current for an ls/platinum plated itria stabilized zirconia cell operated at 748°C using a nitrogen oxide flow with a flow rate of 1.5 t/gni%. . FIG. 19 is a graph of current versus nitrogen oxide concentration for the ittria-stabilized zirconia cell of Example 3. FIG. 20 is a cyclic portamogram of Example 2 101% chromium oxide/calcia stabilized zirconia cell. Figure 21 shows the ittria-stabilized zirconia of Example 21.
Differential gas-phase infrared spectra of No and SOI after passing through the cell (dtffgrm%t<at gas-ph
tssm FT-IR). FIG. 22 is an infrared spectrum of an argon stream bearing N204 before passing through the cell of the present invention. FIG. 23 shows t' after passing through the cell of the present invention shown in FIG.
tt 04 is an infrared spectrum of an argon flow. FIG. 24 is a graph of seal efficiency versus flow rate for the Ittria stabilized zirconia cell of Example 1 at 400°C. Procedural Amendment May 27, 1986 Commissioner of the Patent Office Black 1) Akira! a Display of the case in paragraph 1 1985 Patent Application No. 93447 Z Name of the invention Solid electrochemical pollution control device 3, Relationship with the person making the amendment Case Name of the patent applicant IG-R Enterprises Inc. 4, Agent name Patent attorney (7175) Takehiko Saito π'
..., :1 ゛bi, 1 -Iko-11'' 5. Subject of amendment 7';('',,n Engraving of the handwritten specification attached to the application...1)!
・・・;t 6. Contents of correction
E/Attachment 9, however, there is no amendment to the contents of the specification. Procedural amendment (method) % formula % 1. Indication of the case 1985 Patent Application No. 93447 2. Name of the invention Solid electrochemical pollution control device 3. Person making the amendment Relationship to the case Patent applicant name I.G. R Enterprises Incorporated 4 Agent

Claims (1)

[Claims] 1. A porous, large surface area body; a porous solid electrolyte with a large surface area forming the inner body of the cell and through which a gas flow can flow; from one end of the cell length to the other; a gas communication passageway, a first electronically conductive region and a second electronically conductive region, both regions being located in electronically opposed portions of the vessel; the first electronically conductive region; A solid state electrochemical cell for altering the composition of a gas flow passing therethrough, comprising a first electrode connection member in the second conductive region and a second counter electrode connector member in the second conductive region. 2. Claim 1, wherein the electrolyte is a darkening electrolyte
Electrochemical cell as described in Section. 3. The electricity according to claim 2, wherein the darkening electrolyte has a ring ratio of 0.0001 to 0.9999, and the partition wall portion of the electrolyte has a ring ratio of 0.50 to 0.9999. chemical cell. 4. The crystal lattice of the darkening electrolyte is about 10 ppm to 10
4. An electrochemical cell according to claim 2 or 3, comprising mol % metal of a transition metal or 0.2 to 80 mol % metal of a non-transition metal. 5. a first sealing member disposed in a fluid-tight relationship at a first sealing end of the cell; and a second sealing member disposed in a fluid-tight relationship at a second sealing end of the cell. further comprising a first end in fluid-tight relationship with the cooperating cell end and a second end in fluid-tight relationship with the gas flow exhaust conduit. , an electrochemical cell according to claim 1, 2, 3, or 4. 6. The electrochemical cell of claim 1, 2, 3 or 4, wherein the porous, large surface area solid electrolyte is a metal oxide. 7. The electrochemical cell of claim 6, wherein the porous, high surface area solid electrolyte is a stabilized metal oxide. 8. The porous, large surface area solid electrolyte contains zirconium, hafnium, titanium, calcium, magnesium,
The electricity according to claim 6, which is a metal oxide selected from the group consisting of oxides of cerium, bismuth, samarium, yttrium, scandium, gadolinium, lanthanum, erbium, praseodymium, and molybdenum, perovskite, and pyrochlore. chemical cell. 9. The electrochemical cell according to claim 7, wherein the stabilized metal oxide is yttria-stabilized zirconia. 10. The electrochemical cell according to claim 7, wherein the stabilized metal oxide is calcia-stabilized zirconia. 11. A cell having a large surface area porous solid electrolyte body that allows a gaseous combustion exhaust stream to flow through the cell, the body having a first
an upstream sealing member in fluid-tight relationship with the first end of the cell and an upstream portion of the exhaust conduit; a second end of the cell and an upstream portion of the exhaust conduit; a downstream sealing member in fluid-tight relationship with the downstream portion; a first discrete conductive region over a portion of the cell surface; a second discrete conductive region over a portion of the cell surface; a first electrode connector cooperating with the first separate conductive region; a second electrode connector cooperating with the second separate conductive region; the electrode connector and an alternating current or direct current source; CLAIMS 1. A solid state dry electrochemical scrubber assembly suitable for use in a gaseous combustion exhaust stream containing hazardous components, the solid state dry electrochemical scrubber assembly having cooperating first and second electrodes. 12. Claim 11, wherein the electrolyte is darkened and has a ring ratio of 0.0001 to 0.9999, and the partition wall portion of the electrolyte has a ring ratio of 0.50 to 0.9999. Electrochemical scrubber assembly as described in Section. 13. According to claim 11 or 12, wherein the first and second ends of the cell are formed with a hub structured to engage in a fluid-tight engagement with the opposing socket sealing ends of the sealing member. Scrubber assembly as described. 14. The scrubber assembly of claim 13, wherein the sealing member includes a shoulder member that cooperates with the hub end of the cell to form a fluid-tight seal. 15. The scrubber assembly of claim 11, wherein the porous, high surface area solid electrolyte is a metal oxide electrolyte. 16, the metal oxide electrolyte is zirconia, hafnia, titania, ceria, ittria, scandia, calcia,
16. The scrubber assembly of claim 15, wherein the scrubber assembly is selected from the group consisting of gadolinia and bismuth oxide. 17. The scrubber assembly of claim 16, wherein the metal oxide electrolyte is a stabilized metal oxide electrolyte. 18. The scrubber assembly of claim 17, wherein the stabilized metal oxide electrolyte is yttria stabilized zirconia. 19. The scrubber assembly of claim 17, wherein the stabilized metal oxide electrolyte is calcia stabilized zirconia. 20, first end seal for gas intake, second end seal for gas discharge
a porous, high surface area body with end seals and substantially gas impermeable sidewalls defining the length of the cell; a high surface area, porous solid electrolyte forming the internal cell body; a gas inflow conduit; and the first structure of the fluid-tight interlocking relationship.
a second sealing end spaced apart in a fluid-tight interlocking relationship with the gas flow discharge conduit; 2
a first electronically conductive region and a second electronically conductive region, both of which are connected to the electronically conductive region of the cell; a first electrode connecting member placed in the first conductive region and a second counter electrode connecting member placed in the second conductive region: the cell end portion; is structured to form an airtight interlock with a conduit member for supplying and extracting gas streams for treatment in the cell and for removal from the gas stream treated in the cell, respectively. Solid state electrochemical ceramic cell for altering composition. 21. The electrochemical ceramic cell of claim 20, wherein the electrolyte is a darkened electrolyte. 22. The electrochemical ceramic cell of claim 20 or 21, wherein the porous, high surface area solid electrolyte is a metal oxide. 23. The electrochemical ceramic cell of claim 22, wherein the porous, high surface area solid electrolyte is a stabilized metal oxide.