JPS58174236A - Catalyst for removing particulate matter in waste gas - Google Patents

Abstract

PURPOSE:To enable the combustion of captured particles at such a low temp. at which no thermal impact is given to the capturing body itself by consisting a titled catalyst of at least one component selected from V and V compds. CONSTITUTION:At least one, selected from V and V compds., or at least one selected from V and V compds. is combined with at least one selected among alkali metals, silver, Mg, La, tin, Sb, Cr, Mo, Mn, iron, Co, Ni, Ru, platinum and compds. thereof is used as a component for a catalyst, whereby the catalyst permits to lower the combustion temp. of particles. This catalyst is usable not only as a catalyst for removing particulates contained in the exhaust gas of automotive engines but also for engines of transport means such as cultivators, ships and trains, industrial engines and further combustion furnaces and boilers.

Description

[Detailed description of the invention] Tiki in the middle of the day. Regarding the catalyst that burns the rate, for a moment, in detail: /f- in the exhaust gas, which can burn the rate at a low temperature, which is trapped in the rate trapping body or the purifying body. Ticulate purification catalyst Kl%l.

In recent years, even tiki in exhaust gas. Rates, especially ticulates (fine powder of carbides such as soot) emitted from diesel engine exhaust gas, have been considered a pollution problem since it has been revealed that they contain carcinogenic substances such as pentupyrene. , and regulations on its emissions are about to be implemented.

Traditionally, such parables have been used. - To capture the rate,
The use of trapping bodies such as ceramic honeycombs, ceramics, kutuom, metal wire-filled systems, alumina, etc. (ret-like carrier-filled systems) has been proposed; However, because the accumulation causes clogging,
It is necessary to periodically dispose of the deposits or to remove them by combustion using high-temperature treatment.

However, among these methods, the former method is cumbersome, cannot be effectively removed, and poses a problem in terms of pollution. The latter is 7
It is necessary to raise the temperature to nearly 00℃, and the combustion causes an unfavorable thermal shock to the capture body itself.
0w that may accelerate its deterioration! Furthermore, there is a danger that incomplete combustion may generate toxic gases such as carbon monoxide. For this reason, it has been desired to efficiently burn the 9-year-old ticulate at a lower temperature by trapping it in a ticulate trapping body or purifying body.

The present invention relates to a novel catalyst that allows the trapped Dirticure-1 to be combusted at such a low temperature that it does not give a thermal shock to the trapped body itself.

BACKGROUND ART Conventionally, noble metal catalysts (platinum, platinum, etc.) have been known for converting harmful NOx, carbon oxides, and hydrocarbons through catalytic oxidation of gasoline engine exhaust gas. However, the mechanism of action of this type of catalyst is subject to the present invention. For example, using a platinum catalyst, which is known to be the most effective catalyst for purifying gasoline exhaust gas, 1/l- Effectively burns and treats ticulates.

The media for purifying f-ticulates according to the present invention, as described above, can heat f-ticulates at low temperatures, so it is suitable for use with ceramic honeycombs and cerano.

By supporting the catalyst of the present invention on a p4-ticulate trapping or purifying body made of a porous material, it is possible to reliably capture 9-ticulate in exhaust gas and catalytically burn the p4-ticulate at a lower temperature. Therefore, less energy is required for combustion, and the life of the trapping body or purifying body can be extended. In some cases, the combustion temperature of the /IF in the exhaust gas can be lowered to the exhaust gas temperature.
-Tiki.

It is also possible to capture and burn the rate at the same time, which eliminates clogging of the capture body or purification body and eliminates the need for regeneration operations, or at least eliminates the expense of frequently performing regeneration operations.1! In addition, it has many advantages, such as being able to prevent the generation of toxic gases such as carbon monoxide during the combustion of ``g-ticulate''.

The present invention will be explained in more detail below.

The catalyst for purifying particulates according to the present invention comprises at least one of pananoum and panasoum compounds.
Consists of one. In addition, at least one (a) selected from panazome and pananoum compounds is used as a component, and 6) alkali metals, silver, magnesium, lanthanum, tin, antimony, chromium, molybdenum, manganese, iron,
Cobalt, two.

By combining at least one component selected from chelate, ruthenium, platinum, and their compounds, it is possible to obtain a catalyst that is capable of reducing the combustion temperature of the arm ticulate.

Here, as pananoum and pananoum compounds,
Metallic pananium, ammonium panazonate, pananol dinitride, pananonium oxytrichloride, -acid pananol, panazome pentoxide, pananium trioxide, pananoum difluoride, pananium trichloride, pananium tetrachloride, lithium pananonate, panasonic acid Examples include sodium, potassium panazonate, and their oxides and calcined products.
The catalyst of the present invention exhibits sufficient effects with the above-mentioned Yanazoum component alone, but can also effectively achieve low-temperature combustion of one component. Here, specific examples of component (b) include alkali metals (lithium, sodium, potassium, etc.), silver, magnesium, lanthanum, tin, antimony, chromium, molybdenum, manganese, iron, cobalt, nickel, rutheni, Platinum, platinum, and their compounds, and the types of compounds include oxides, nitrates, halodides, cardanates, sulfites, nitrates, and phosphorus #I! A platform etc. can be given. Among them, oxides are preferably used. In addition, among the above components (b), antimony, alkali metals,
Molybdenum, iron, chromium, tin, ruthenium, platinum and lanthanum are preferred.

In the present invention, when the above-mentioned (a) component and (b) component are combined, the ratio to be used is not particularly limited and they can be used in combination at any desired ratio, but the above-mentioned (a) component The molar ratio of component (b) is 9.510.5 to 1/9
It is particularly preferable to combine in the range of 8/2 to 4A, and the molar ratio in this range is very efficient.
This makes it possible to perform low-temperature combustion processing.

Furthermore, the above-mentioned catalyst system, i.e. component (a) alone or (
It is also possible to use a solid acid as a carrier for the combination system of component (turtle) and component (b). A metal complex oxide is preferably used.

Specifically, as solid acids, titania, oxide, magnesia, zinc oxide, cadmium oxide, aluminum, silica,
One or more combinations of zirconia, lead oxide, bismuth oxide, iron oxide, etc., zinc oxide and magnesia, aluminum, silica, zirconia, lead oxide, aluminum oxide/timo/1
, a combination of one or more elements such as bismuth oxide, a combination of alumina and one or more elements such as magne, boron oxide, zirconia, antimony oxide, bis oxide, boria, etc., a combination of silica and magnesia, calcium oxide,
Examples include one or a combination of two or more of strontium oxide, barium oxide, gallium oxide, aluminum oxide, yttrium oxide, lanthanium oxide, zirconia, and cadmium oxide. Note that one type of the above combination may be used, or two or more of the above combinations may be used!
Among the above combinations, which may be used in combination with:
Titania-alkiss, titania-silica, titania-solconia, silica-alumina, silica-zirconia, or combinations thereof may be suitably used.

When using the above-mentioned nota oxides in combination, their combined use ratio #
'i%K111J@ not included, but titania, aluminum power,
Preferably, silica, zirconia, and zinc oxide are contained in the solid acid in an amount of 5 to 95 moles.

Note that any method can be used to attach the catalyst to the monolithic acid.

The catalyst of the present invention can be carried on a suitable carrier, such as ceramic.

It can be used by forming a layer on a capture body such as a support pellet-filled thread such as Kutuom, Ceramic, Kutuhoum, Metal Wire Filled System, Aluminum Force, etc. 9. When using a solid acid, for example, a layer of oxide such as r-alumina, silica, magnesia, titania, etc. is formed on the surface of the trapped body, and then a solid acid layer is formed. However, a method is adopted in which a catalyst is deposited on the layer.

A preferred trapping body is a ceramic foam, and a specific example thereof is one in which internal communication spaces are formed at a rate of 6 to 150 pieces per inch, and the bulk specific gravity is 0.25 to 1.0. It is within the range of It is possible to arrange only one of these ceramic forms of the desired size, but it is also possible to use a combination of multiple forms. It is also possible to construct a structure by sequentially laminating two layers. Of course, the method of adhering the catalyst may also be changed as necessary.

(9) The catalyst of the present invention has 1. It can also be used more effectively in combination with a known catalyst, such as a catalyst for gasoline engine exhaust gas (containing or not containing carbon dioxide).

The trapping body or purifying body carrying the catalyst of the present invention is used by being placed in a predetermined flow path of exhaust gas of an engine or the like.
Exhaust gas from an engine, etc. passes through the exhaust gas flow path of a capture body or purification body placed in the middle of the flow path, and during the passage, soot and t4-ticulates such as pentupyrene in the exhaust gas are removed. It was well captured and the captured armpit
Due to the action of the catalyst of the present invention, the ticulate is completely twisted at a temperature 200 to 300° C.St lower than when no catalyst is used.

The catalyst of the present invention is useful not only for exhaust gas from automobile engines, but also for transportation engines such as tillers, ships, and trains, industrial engines, combustion furnaces, blowers, etc.
It can be used for removing ticulates.

EXAMPLES Hereinafter, the present invention will be explained in more detail by showing Examples and Comparative Examples.

[Example 1] Ammonium panasonic acid (NH4VO,) 0.435
．． 9 (3,7m mot) into a 10d beaker,
Pure water 4d.

Oxalic acid 1. Ol was added and dissolved.

Add 0.5 N of silica-alumina (silica/aluminium (S = 85/15 (% ratio)) to this solution as a catalyst carrier.
The mixture was stirred with a glass rod on a hot grate and dried for about 10 minutes.

Next, it was vacuum dried at 200C for 120 minutes, and then heated in an electric furnace at 70oC for 30 minutes. The catalyst supported on the carrier obtained in this manner and Noyatiki and Leto collected from diesel engine exhaust gas were mixed at a weight ratio of 1:1, and the combustion behavior thereof was measured using a thermogravimetric measuring device.

The test conditions were: sample weight 40~, air supply amount 0.5
t/min, the heating rate was 2 (L°C/min), and the combustion temperature was determined from the weight reduction curve. As a result, the combustion temperature was 437°C.

For comparison, the same experiment was repeated in a system in which no panazoum component was present.
The temperature was 1635°C.

[Example 2] Using almost the same method as in Example 1, however, as a catalyst component,
Ammonium panazonate (NH4VO3) 0.3261
1 (2,78 mmoz) and 1 compound is AMnC12.4
H20) using 0,1841 (0,92 mmot),
In addition, a catalyst was prepared using silica aluminum 0.51 as a carrier, and a diesel fuel combustion experiment was conducted.As a result, the combustion temperature of diesel fuel was 391℃.
It has been found that the combination of manganese compounds has the effect of significantly lowering the combustion temperature compared to panazome alone.

[Examples 3 to 16] Catalysts were prepared under the same pressure as in Example 2, but by combining ammonium panazonate and the compounds shown in Table 1, and combustion experiments of 9-tiki and lattice were conducted. In both cases, it is clear that the chemotactic compound shown in Table 1 has the effect of reducing the combustion temperature compared to the panazome catalyst alone. Table 1 [Example 17] 920 internal communication spaces per inch A ceramic form made of cordierite material (a circle with a cross-sectional force of 9.51,
A cylinder having a length of 103 mm) was immersed in an aqueous solution containing 74 nazonic acid ammonite manpun chloride (molar ratio: 3:1) by weight of t-15. The sample was taken out from the solution, excess solution was removed using a centrifuge, and the sample was dried, followed by baking at 700° C. for 30 minutes in air.

This ceramic foam was installed 1.5 m from the exhaust port of a diesel engine (Qin), and the vehicle was run for 30 minutes at a rotation speed of 900 rpm and a torque of 8.9 Um.
5I diesel/4-ticulate was captured.

A cube of approximately 21 sides was cut out from the center of the ceramic foam, and the combustion temperature of the graphite was measured using a thermogravimetric measuring device, and the value was 385C.

Ninth comparison, when a similar experiment was conducted on ceramic foam that did not support a catalyst, the combustion temperature was 650°C.
Met.

As mentioned above, it has been found that the pananium manganese catalyst, when supported on cerium hydride, has a great effect on lowering the combustion temperature of diesel and ticulate.

((transformation) Isuzu Diemini, exhaust jll1800a.

Applicant Brideston Tire Co., Ltd. Daishioiri Patent attorney Takashi Kojima Patent attorney Hajime Takahata

Claims (1)

[Scope of Claims] 1.9- in the exhaust gas, which is characterized by consisting of at least one selected from vanadium and vanadium compounds.
Catalyst for ticulate purification. 2(1) At least one selected from vanadium and vanadium compounds, (alkali metals, scissors, magnesium, lanthanum, tin, antimony, chromium, molyden, manganese,
1. A catalyst for purifying ticulate in exhaust gas, characterized in that it is made of a combination of at least one selected from iron, cobalt, nickel, ruthenium, platinum, and compounds thereof.