CN108579745A - A kind of monoblock type VOCs oxidation catalysts and preparation method thereof - Google Patents

Abstract

The invention relates to an integral VOCs oxidation catalyst and a preparation method thereof. The monolithic VOCs oxidation catalyst includes a carrier, a catalyst coating uniformly embedded in the carrier and uniformly distributed on the surface of the carrier, and active components and additives uniformly dispersed in the catalyst coating, wherein the The carrier is an integral corrugated fiber paper carrier formed by rolling or laminating corrugated fiber paper substrates. The preparation process of the catalyst is simple, the cost is low, and it is easy to realize industrialization, and the prepared monolithic VOCs oxidation catalyst has excellent catalytic activity, thermal stability and water resistance, high geometric specific surface area, and low catalyst density. It is a conventional cordierite material. 60‑70% of , can be ignited quickly, so that the rapid progress of the catalytic oxidation reaction can be used.

Description

A kind of monolithic VOCs oxidation catalyst and preparation method thereof

technical field

The invention relates to an environmental catalytic material and a preparation method thereof, in particular to an integral VOCs oxidation catalyst and a preparation method thereof, and belongs to the technical field of air pollution control.

Background technique

Volatile organic pollutants (VOCs), SO ₂ , NOx, dust, and motor vehicle exhaust are important pollutants in the atmospheric environment, causing serious harm to human health, and are secondary pollutants such as acid rain, O ₃ , and PM2.5 main precursor.

Catalytic-oxidation method is an effective means to eliminate VOCs emitted by industry. VOCs molecules are adsorbed on the surface of the catalyst and activated, and undergo a rapid oxidation reaction with _O2 at a lower temperature, and the product molecules _CO2 and _H2O are desorbed from the surface of the catalyst. , with the characteristics of high efficiency, stability and cleanliness. Compared with the ordinary thermal combustion method, the catalyst can reduce the activation energy of VOCs molecules, so that it can undergo a flameless oxidation reaction at a lower temperature, and can completely oxidize VOCs within a wide range of air excess coefficients.

The core of the catalytic-oxidation method is the catalyst, which requires the catalyst to be able to withstand operating conditions such as high temperature, high water content, and wide air excess coefficient, as well as have certain anti-poisoning properties. In addition, specific surface area, pore structure and size, active metal dispersion and heat capacity are important parameters affecting catalyst performance. The catalyst for engineering application uses cordierite honeycomb ceramics as a carrier, and the surface is coated with noble metal (Pt, Pd, Rh, Au, etc.) active components and rare earth oxide additives.

Patent CN 104667947 discloses block-distributed noble metal composite oxide VOCs catalyst, and patent CN102481549 discloses an oxidation catalyst for destroying CO, VOC and halogenated VOC, with cordierite honeycomb ceramics as the carrier, coated with coating and noble metal active components Deposited, the coating provides a larger specific surface area to disperse precious metal active components. The catalyst has high activity, but the process is complicated and there are many procedures, including coating-drying-calcination-precipitation of noble metal active components-secondary drying-secondary roasting. The coating has a porous structure, capillary action is conducive to the competitive adsorption and enrichment of noble metal ions, and it is not easy to control the loading of noble metals. During the subsequent drying process, noble metal ions can migrate to the surface of the coating and aggregate, which further affects the dispersion and particle size control of active particles. In addition, the aggregation of active particles and their weak interaction with the coating lead to uneven distribution of active particles, reduced dispersion, and larger particle size, and high temperature causes active particles to migrate and aggregate to affect activity. Patent CN106378132 discloses two kinds of organic waste gas purification catalysts, one is different shapes (spherical, strip and ring) Al ₂ O ₃ supports impregnated in the precursor salt solution, supporting noble metals and transition metal oxides; the other is The coated catalyst is prepared by impregnating honeycomb ceramics in noble metal, transition metal and additive salt solution. The catalyst preparation process is complicated and the conditions need to be precisely controlled. Patent CN106732579 adopts vacuum coating method to prepare nano-noble metal monolithic catalyst for low-temperature catalytic combustion of organic waste gas, adopts one-step method to load coating and noble metal, mixes active alumina, cerium zirconium and rare earth oxide precursor powder with deionized water, and ball mills The noble metal salt solution is added to obtain a coating slurry, and the coating and active components are coated on the surface of the cordierite honeycomb ceramics. The cordierite carrier needs to be pretreated with nitric acid, and the process is relatively complicated, which is not conducive to maintaining the strength and durability of the carrier. The catalytic combustion catalyst disclosed by the patent CN106540754 uses ceramic fibers as a carrier to support coatings and noble metal active components. The ceramic fiber carrier needs to be soaked in acid solution, pretreated with high-temperature water vapor, and then loaded with coating and active components in two steps. The catalyst has high activity and stability for CO oxidation, but the process is complicated and there are many procedures. In addition, the coating forms a well-developed pore structure after drying and calcination, which makes it difficult to control the loading of active components. The active components loaded with precious metals tend to aggregate, resulting in larger active particles, which in turn affects performance. Catalysts are prone to sintering and deactivation at high temperatures. .

VOCs oxidation catalysts have disadvantages such as complex preparation process, numerous procedures, and utilization of active components. The existing catalysts mainly use cordierite honeycomb ceramics as the carrier, and the shape and structure are not easy to adjust the specific gravity of the catalyst according to the requirements. The heat capacity is large, the ignition is slow, and the specific surface area Low, reducing catalyst performance and increasing operating energy consumption.

Contents of the invention

The purpose of the present invention is to provide a monolithic VOCs oxidation catalyst and a preparation method thereof. The preparation process of the catalyst is simple, the cost is low, and it is easy to realize industrialization, and the prepared monolithic VOCs oxidation catalyst has excellent catalytic activity, thermal stability and Water resistance, high geometric specific surface area, low catalyst density, which is 60-70% of conventional cordierite material, and can be quickly ignited, so that the rapid catalytic oxidation reaction can be used.

The present invention provides a monolithic VOCs oxidation catalyst, comprising a carrier, a catalyst coating uniformly embedded in the carrier and evenly distributed on the surface of the carrier, and active components and auxiliary components uniformly dispersed in the catalyst coating. agent, wherein the carrier is an integral corrugated fiber paper carrier formed by rolling or laminating corrugated fiber paper substrates.

The integral corrugated fiber paper carrier is a refractory fiber substrate, and its microstructure is an interwoven network structure. The existence form of the catalyst coating on the integral corrugated fiber paper carrier is: embedded in the interior of the integral corrugated fiber paper carrier and attached to the surface of the integral corrugated fiber paper carrier. The active component and the auxiliary agent are dispersed in the catalyst coating to form a mixed system with the catalyst coating. The monolithic VOCs oxidation catalyst is used for the efficient removal of VOCs organic waste gas, the catalyst has excellent catalytic activity and thermal stability, and the catalyst coating is evenly embedded in the interwoven network structure of the monolithic corrugated fiber paper carrier , has a strong binding force.

Further, the corrugated fiber paper base material is formed by bonding and compounding corrugated corrugated refractory fiber paper and planar refractory fiber paper, by rolling or stacking the corrugated fiber paper base material to form a catalyst-coated base material. Layers and channels through which air flows, wherein the corrugated corrugated refractory fiber paper is obtained by processing the planar refractory fiber paper.

Wherein the planar refractory fiber paper of the corrugated fiber paper base material can be combined with the adjacent corrugated refractory fiber paper in the process of winding or stacking, so as to form channels.

Further, the material of the planar refractory fiber paper is high temperature resistant fiber, and the high temperature resistant fiber includes one or more of ceramic fiber, basalt fiber, glass fiber, quartz fiber and mullite fiber.

Further, the catalyst coating includes activated alumina, cerium-zirconium oxygen storage material and rare earth oxide, wherein the alumina, the cerium-zirconium oxygen storage material and the rare earth oxide are in the ratio of 10-70:85-10: The mass ratio of 5-20 is mixed, the activated alumina is γ-Al ₂ O ₃ , the cerium-zirconium oxygen storage material is Cex Zr _{1-x O 2} , where 0<x<1 and the rare earth oxide One or any of the oxides of La, Ce, Pr, Nd and Y.

Wherein, the coating amount of the catalyst coating is 80-300g/L.

Further, the active component includes one or any of noble metals, noble metal salts and noble metal oxides, and the noble metals are one or any of Pd, Pt, Rh, Ru, Re, Au and Ag Several types, calculated as elemental metal, the loading amount of the active component in the catalyst layer is 10-100 g/ft ³ .

Further, the auxiliary agent includes a first auxiliary agent and/or a second auxiliary agent, wherein the first auxiliary agent includes one or both of a salt of a transition metal and an oxide of a transition metal, and the transition metal is One or more of Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn, in terms of oxides, the loading of the first promoter in the catalyst coating is 1- 20wt% (3-60g/L); and the second auxiliary agent includes one or both of alkali metal salts and alkali metal oxides, and the alkali metals are Li, Na, K, Rb and Cs One or more of them, based on elemental metal, the loading amount of the second additive in the catalyst coating is 0.05-10wt% (0.04-3g/L).

In the present invention, the first auxiliary agent or the second auxiliary agent can be selected according to the actual situation, or the first auxiliary agent and the second auxiliary agent can be used together.

The present invention also provides a method for preparing an integral VOCs oxidation catalyst, which adopts a one-step coating process, and coats the catalyst coating composition, active components and additives on the integral corrugated fiber paper carrier by vacuum coating .

Further, it includes the step of preparing an integral corrugated fiber paper carrier: rolling or laminating the corrugated fiber paper base material formed by bonding and compounding corrugated corrugated fire-resistant fiber paper and planar fire-resistant fiber paper into a cylinder or a cube Integral corrugated fiber paper carrier, wherein the corrugated fiber paper substrate is made of corrugated corrugated fire-resistant fiber paper and planar fire-resistant fiber paper bonded and composited, and the corrugated fiber paper substrate is formed by rolling or laminating the corrugated fiber paper substrate. A channel for the catalyst-coated catalyst layer and airflow to pass through is formed, wherein the corrugated corrugated refractory fiber paper is obtained by processing the planar refractory fiber paper.

Further, including the step of coating the catalyst coating composition, the active component and the auxiliary agent:

1) After mixing the first auxiliary agent and/or the second auxiliary agent in deionized water, add the binder and the third auxiliary agent and stir for 0.5-2h to obtain a mixed solution; A mixed slurry is obtained by adding alumina, cerium-zirconium oxygen storage material and rare earth oxide at a mass ratio of 10:5-20, wherein the total mass of the alumina, the cerium-zirconium oxygen storage material and the rare earth oxide is the same as the The mass ratio of deionized water is 1:9-5:5.

2) Using an acid to adjust the pH of the mixed slurry to 3-6, then ball-milling the mixed slurry for 0.5-2 hours, adding the active component, and then continuing to ball-mill for 0.5-2 hours to obtain a coating slurry;

3) using the coating slurry to vacuum coat the integral corrugated fiber paper carrier for 1-15 minutes, and purging the channels with vacuum to facilitate the uniform distribution of the coating slurry;

Among them, there is excess coating slurry in the channel after coating. In order to control the coating amount of the catalyst coating, purging is required. The catalyst coating is not uniform after coating, and the uniformity of the catalyst coating can also be improved by purging. .

4) After coating the coating slurry on the integral corrugated fiber paper carrier, dry it under hot air at 60-200°C for 10-60min, and then bake it in air at 300-600°C for 1-8h, so as to obtain the integral Formula VOCs oxidation catalyst.

Further, the binder in the step 1) is one of silica sol, aluminum sol, silica-alumina sol, titanium sol, aluminum dihydrogen phosphate and pseudo-boehmite or obtained by mixing any of them In terms of solids, the amount of the binder added is 1-30wt% of the total mass of the alumina, the cerium-zirconium oxygen storage material and the rare earth oxide in the mixed slurry;

The third auxiliary agent in the step 1) is polyvinyl alcohol, butylene glycol, polyethylene glycol, Tween-20, polyurethane, modified polyurethane, acrylate, modified polyacrylate, polyacrylate , polycarboxylate, organosiloxane, polyether-modified organosiloxane, polyester-modified organosiloxane, fatty alcohol polyoxyethylene ether and cellulose, or any mixture of them , the addition amount of the third additive is 0.1-10wt% of the total mass of the alumina, the cerium-zirconium oxygen storage material and the rare earth oxide in the mixed slurry; and

Wherein, the third auxiliary agent is a coating auxiliary agent, which is mainly used to adjust the properties of the coating slurry and optimize the coating effect, specifically to optimize the viscosity of the slurry and improve the adhesion, uniformity and leveling of the coating.

The acid in the step 2) is one of nitric acid, hydrochloric acid, sulfuric acid, acetic acid, oxalic acid and citric acid or obtained by mixing any of them.

Another object of the present invention is that the material of the integral corrugated fiber paper carrier included in the integral VOCs oxidation catalyst is high temperature resistant fiber, including ceramic fiber, basalt fiber, glass fiber, high silica fiber, quartz fiber, mullite One or any combination of stone fiber and ceramic fiber-glass fiber composite has a high geometric surface area, and the shape structure and channel size can be processed into cylinders or cubes with different sizes according to needs.

The monolithic VOCs oxidation catalyst prepared by the present invention has simple process, low cost and excellent catalyst performance. Compared with the prior art, the present invention has the following advantages:

The invention uses the high-temperature-resistant corrugated fiber paper substrate as a carrier, freely adjusts the shape structure and pore size according to actual needs, has a large porosity, can anchor the catalyst coating, and improves the life of the catalyst;

The monolithic VOCs oxidation catalyst has a low density and low heat capacity, which is only 60-70% of that of cordierite honeycomb, which significantly reduces the mass of the reactor, and the catalyst can light up quickly;

The monolithic VOCs oxidation catalyst of the present invention adopts a one-time coating process to realize coating coating and the loading of active components and additives, optimizes the preparation process, avoids the disadvantages caused by step-by-step coating, and can precisely control the thickness of the coating. The coating amount and the loading capacity of the active component noble metal; the active component noble metal particles are highly dispersed in the coating, and the coating anchors the active component noble metal particles, which eases the migration and aggregation of the active component noble metal particles, and improves the catalytic activity of the catalyst. stability and durability;

The monolithic VOCs oxidation catalyst of the present invention can be applied to the processing equipment for processing VOCs by the catalytic-oxidation method, and can also be applied to the VOCs waste gas treatment system in industries such as coating, printing, chemical spray paint, etc. Concentration, activated carbon fiber adsorption, condensation and other treatment technologies are used in combination to achieve excellent treatment effects.

Description of drawings

Fig. 1 is a structural representation of the monolithic VOCs oxidation catalyst prepared by the present invention;

Fig. 2 is another structural representation of the monolithic VOCs oxidation catalyst prepared by the present invention;

Fig. 3 is the partial structure schematic diagram of monolithic VOCs oxidation catalyst prepared by the present invention;

Fig. 4 is a graph showing the activity of monolithic VOCs oxidation catalysts prepared in Examples 1-3 and Comparative Examples of the present invention.

Detailed ways

The principles and features of the present invention will be described below in conjunction with the drawings and embodiments, and the embodiments are only used to explain the present invention, not to limit the scope of the present invention.

The monolithic VOCs oxidation catalyst of the present invention may be a coiled monolithic VOCs oxidation catalyst (see FIG. 1 ), or a laminated monolithic VOCs oxidation catalyst (see FIG. 2 ). Referring to Fig. 3, the monolithic VOCs oxidation catalyst of the present invention includes a carrier, a catalyst coating 11 uniformly embedded inside the carrier and evenly distributed on the surface of the carrier, and an active group uniformly dispersed in the catalyst coating 11 A dispensing and auxiliary agent, wherein the carrier is an integral corrugated fiber paper carrier rolled or laminated with corrugated fiber paper substrates. The corrugated fiber paper substrate is made of single-sided corrugated refractory fiber 12 and planar refractory fiber paper 13. The corrugated corrugated refractory fiber paper and the planar refractory fiber paper are bonded to each other to form a channel for the catalyst coating to pass through, wherein the corrugated corrugated refractory fiber paper is formed by the planar refractory fiber paper. It is obtained by processing refractory fiber paper.

In order to illustrate the present invention better, provide following embodiment specially:

Example 1

Carrier: integral carrier of ceramic fiber substrate, inch

Mix 0.45g Na ₂ CO ₃ with 290mL deionized water, add 2.4g PEG and 24g aluminum sol (20wt%), and stir to obtain a mixed solution. Add 86.8g of active Al ₂ O ₃ , 24.8g of cerium-zirconium oxygen storage material, 6.2g of La ₂ O ₃ and 6.2g of Y ₂ O ₃ , stir well and adjust the pH to 3-4 with HNO ₃ , add 4g of Pd after 30min of ball milling (NO ₃ ) ₂ continued ball milling for 1 h to obtain coating slurry.

The slurry is coated on the carrier by a vacuum coating machine, coated for 2-3 minutes and vacuum purged, dried with hot air at 120° C. for 30 minutes, and calcined in an air atmosphere at 500° C. for 4 hours to obtain a monolithic VOCs oxidation catalyst. The coating amount of the coating layer on the catalyst was 123 g/L, and the loading amount of the noble metal was 0.61 g/L Pd.

Example 2

Carrier: integral carrier of ceramic fiber substrate, inch

Mix 0.39g Na ₂ CO ₃ with 290mL deionized water, add 1.8g PEG and 18g aluminum sol (20wt%), and stir to obtain a mixed solution.

Add 86.8g of active Al ₂ O ₃ , 24.8g of cerium-zirconium oxygen storage material, 6.2g of La ₂ O ₃ and 6.2g of Y ₂ O ₃ , stir well and adjust pH=3-4 with HNO ₃ , add 2.8g of Pd(NO ₃ ) ₂ and 1.2g Pt(NO ₃ ) ₂ were ball milled for 1 hour to obtain a coating slurry.

The slurry is coated on the carrier by a vacuum coating machine, coated for 2-3 minutes and vacuum purged, dried with hot air at 120° C. for 30 minutes, and calcined in an air atmosphere at 500° C. for 4 hours to obtain a monolithic VOCs oxidation catalyst. The coating weight of the coating on the catalyst was 128 g/L, and the noble metal loadings were 0.44 g/L Pd and 0.18 g/L Pt.

Example 3

Carrier: glass fiber substrate monolithic carrier, inch

0.52g Na ₂ CO ₃ , 24.96g Mn(NO ₃ ) ₂ were mixed with 290mL deionized water, 1.8g PEG and 6g pseudo-boehmite were added, and stirred to obtain a mixed solution. Add 24.8g of active Al ₂ O ₃ , 86.8g of cerium-zirconium oxygen storage material, 6.2g of La ₂ O ₃ and 6.2g of Y ₂ O ₃ , stir well and adjust pH=3-4 with HNO ₃ , add 2.8g of Pd(NO ₃ ) ₂ and 1.2g Pt(NO ₃ ) ₂ , continue ball milling for 1h to obtain coating slurry.

The slurry is coated on the carrier by a vacuum coating machine, coated for 2-3 minutes and vacuum purged, dried with hot air at 120° C. for 30 minutes, and calcined in an air atmosphere at 500° C. for 4 hours to obtain a monolithic VOCs oxidation catalyst. The coating weight of the coating on the catalyst is 134g/L, the loading of _MnO2 in the coating is 5wt%, and the loading of noble metals is 0.47g/L Pd and 0.2g/L Pt.

Example 4

Carrier: basalt fiber substrate monolithic carrier, inch

0.61g NaNO ₃ , 14.15g Cu(NO ₃ ) ₂ were mixed with 308mL deionized water, 2.4g PEG and 6g pseudo-boehmite were added, and stirred to obtain a mixed solution. Add 24.8g of active Al ₂ O ₃ , 86.8g of cerium-zirconium oxygen storage material, 6.2g of La ₂ O ₃ and 6.2g of Y ₂ O ₃ , stir well and adjust pH=3-4 with HNO ₃ , add 2.8g of Pd(NO ₃ ) ₂ and 1.2g Pt(NO ₃ ) ₂ , continue ball milling for 1h to obtain coating slurry.

The slurry is coated on the carrier by a vacuum coating machine, coated for 2-3 minutes and vacuum purged, dried with hot air at 120° C. for 30 minutes, and calcined in an air atmosphere at 500° C. for 4 hours to obtain a monolithic VOCs oxidation catalyst. The coating weight of the coating on the catalyst is 118g/L, the loading of _MnO2 in the coating is 5wt%, and the loading of noble metals is 0.41g/L Pd and 0.17g/L Pt.

Example 5

Carrier: high silica fiber substrate monolithic carrier, inch

Mix 0.48g NaNO ₃ with 308mL deionized water, add 1.2g PVA and 4.8g pseudo-boehmite, and stir to obtain a mixed solution. Add 49.6g of active Al ₂ O ₃ , 49.6g of cerium-zirconium oxygen storage material, 12.4g of La ₂ O ₃ and 12.4g of Pr ₆ O ₁₁ in succession, stir well and adjust pH=3-4 with HNO ₃ , add 1.49g after ball milling for 30min Pd(NO ₃ ) ₂ and 3.47g Pt(NO ₃ ) ₂ were ball milled for 1 hour to obtain a coating slurry.

The slurry is coated on the carrier by a vacuum coating machine, coated for 2-3 minutes and vacuum purged, dried with hot air at 120° C. for 30 minutes, and calcined in an air atmosphere at 500° C. for 4 hours to obtain a monolithic VOCs oxidation catalyst. The coating weight of the coating on the catalyst was 128 g/L, and the noble metal loadings were 0.24 g/L Pd and 0.56 g/L Pt.

Example 6

Carrier: integral carrier of ceramic fiber-glass fiber composite substrate, inch

Mix 0.56g Na ₂ CO ₃ with 308mL deionized water, add 1.8g PEG and 6g pseudo-boehmite, and stir to obtain a mixed solution. Add 24.8g of active Al ₂ O ₃ , 86.8g of cerium-zirconium oxygen storage material, 6.2g of La ₂ O ₃ and 6.2g of Y ₂ O ₃ , stir well and adjust the pH to 3-4 with HNO ₃ , add 2.52g after ball milling for 30min Pt(NO ₃ ) ₂ and 1.47g Ru(NO)(NO ₃ ) ₃ (30wt%) were ball milled for 1 hour to obtain a coating slurry.

The carrier and coating slurry are placed on a vacuum coating machine, coated for 2-3 minutes and vacuum purged, dried with hot air at 120°C for 30 minutes, and calcined in an air atmosphere at 500°C for 4 hours to obtain a monolithic VOCs oxidation catalyst. The coating weight of the coating on the catalyst was 115 g/L, and the precious metal loading was 0.40 g/L Pt and 0.42 g/L Ru.

comparative example

Carrier: cordierite honeycomb ceramics, inch, 300 mesh

Mix 0.39g Na ₂ CO ₃ with 210mL deionized water, add 2.4g PEG and 24g aluminum sol (20wt%), and stir to obtain a mixed solution. Add 86.8g of active Al ₂ O ₃ , 24.8g of cerium-zirconium oxygen storage material, 6.2g of La ₂ O ₃ and 6.2g of Y ₂ O ₃ , stir well and adjust pH=3-4 with HNO ₃ , add 2.8g of Pd(NO ₃ ) ₂ and 1.2g Pt(NO ₃ ) ₂ were ball milled for 1 hour to obtain a coating slurry.

The slurry is coated on the carrier by a vacuum coating machine, coated for 2-3 minutes and vacuum purged, dried with hot air at 120° C. for 30 minutes, and calcined in an air atmosphere at 500° C. for 4 hours to obtain a monolithic VOCs oxidation catalyst. The coating weight of the coating on the catalyst was 125 g/L, and the noble metal loadings were 0.44 g/L Pd and 0.18 g/L Pt.

test case

In the fixed-bed VOCs oxidation catalyst activity evaluation platform to evaluate the catalyst activity, the monolithic catalyst prepared by the embodiment and the comparative example is cut and sampled, and the The catalyst is loaded into the reactor and fixed, and the reaction gas enters the catalytic reactor after being preheated by an electric heater. Before use, the catalyst is activated in the reaction atmosphere for 1-2h, with xylene as the simulated pollutant, the concentration C=4-6g/ ^m3 , the reaction space velocity SV=30000h ^-1 , and the single-point conversion rate at different temperature points is measured. After each temperature point was stabilized for 30 minutes, it was tested, and the VOCs conversion rate was calculated using the catalyst inlet and outlet concentrations. The results are shown in Table 1 and Figure 4.

Table 1

Example 260°C 280°C 300℃ 320°C The VOCs transformation rate of embodiment 1 97.7% 98.4% 99.2% 99.3% The VOCs transformation rate of embodiment 2 97.2% 98.6% 99.2% 99.4% The VOCs transformation rate of embodiment 3 97.0% 98.4% 99.3% 99.6% The VOCs transformation rate of embodiment 4 97.9% 98.1% 99.1% 99.4% The VOCs transformation rate of embodiment 5 97.4% 98.9% 99.9% 99.7% The VOCs conversion rate of embodiment 6 97.6% 98.7% 99.9% 99.9% VOCs conversion rate of comparative example 95.3% 96.3% 98.1% 98.5%

It can be seen from Table 1 and Figure 4 that the monolithic VOCs oxidation catalyst of the present invention has a higher VOCs conversion rate than the catalyst supported by cordierite honeycomb ceramics.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within range.

Claims (10)

1. A monolithic VOCs oxidation catalyst, characterized in that it comprises a carrier, a catalyst coating uniformly embedded inside the carrier and uniformly distributed on the surface of the carrier, and an active group uniformly dispersed in the catalyst coating The dispensing and auxiliary agent, wherein the carrier is an integral corrugated fiber paper carrier formed by rolling or laminating corrugated fiber paper substrates. 2. The monolithic VOCs oxidation catalyst as claimed in claim 1, wherein the corrugated fiber paper substrate is formed by bonding and compounding corrugated corrugated refractory fiber paper and planar refractory fiber paper, Making or stacking the corrugated fiber paper base material to form channels for the catalyst-coated catalyst layer and airflow to pass through, wherein the corrugated corrugated refractory fiber paper is obtained by processing the planar refractory fiber paper. 3. monolithic VOCs oxidation catalyst as claimed in claim 2, is characterized in that, the material of described planar refractory fiber paper is high temperature resistant fiber, and described high temperature resistant fiber comprises ceramic fiber, basalt fiber, glass fiber, quartz One or more of fiber and mullite fiber. 4. The monolithic VOCs oxidation catalyst as claimed in claim 1, wherein the catalyst coating comprises activated alumina, cerium-zirconium oxygen storage materials and rare earth oxides, wherein the alumina, the cerium-zirconium storage The oxygen material and the rare earth oxide are mixed in a mass ratio of 10-70:85-10:5-20, the activated alumina is γ-Al ₂ O ₃ , and the cerium-zirconium oxygen storage material _is Cex Zr _{1 -x} O ₂ , wherein 0<x<1 and the rare earth oxide is one or any combination of oxides of La, Ce, Pr, Nd and Y. 5. monolithic VOCs oxidation catalyst as claimed in claim 1, is characterized in that, described active component comprises one or more in the oxide of noble metal, noble metal salt and noble metal, and described noble metal is Pd, One or more of Pt, Rh, Ru, Re, Au and Ag, calculated as elemental metal, the loading amount of the active component on the catalyst is 10-100g/ft ³ . 6. The monolithic VOCs oxidation catalyst as claimed in claim 1, wherein the auxiliary agent comprises a first auxiliary agent and/or a second auxiliary agent, wherein the first auxiliary agent comprises a salt of a transition metal and a transition metal One or two of metal oxides, the transition metal is one or any of Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn, in terms of oxides, the The loading amount of the first auxiliary agent in the catalyst coating is 1-20wt%; and the second auxiliary agent includes one or both of alkali metal salts and alkali metal oxides, and the alkali metal It is one or any several of Li, Na, K, Rb and Cs, and the loading amount of the second additive in the catalyst coating is 0.05-10wt% in terms of elemental metal. 7. A method for preparing an integral VOCs oxidation catalyst, characterized in that, using a one-step coating process, the catalyst coating composition, active components and auxiliary agents are coated on the integral corrugated fiber paper carrier by vacuum coating superior. 8. the preparation method of monolithic VOCs oxidation catalyst according to claim 7, is characterized in that, comprises the step of preparing monolithic corrugated fiber paper carrier: will comprise corrugated corrugated refractory fiber paper and planar refractory fiber paper bonded The combined corrugated fiber paper substrate is rolled or laminated into a cylindrical or cubic integral corrugated fiber paper carrier, wherein the corrugated fiber paper substrate is composed of corrugated corrugated refractory fiber paper and planar refractory fiber paper It is bonded and compounded with each other, and the channels for the catalyst coating catalyst coating and air flow to be formed are formed by rolling or laminating the corrugated fiber paper substrate, wherein the corrugated corrugated refractory fiber paper is composed of the flat surface It is obtained by processing refractory fiber paper. 9. The preparation method of monolithic VOCs oxidation catalyst according to claim 8, is characterized in that, comprises the step of coating described catalyst coating composition, described active component and described auxiliary agent: 1) After mixing the first auxiliary agent and/or the second auxiliary agent in deionized water, add the binder and the third auxiliary agent and stir for 0.5-2h to obtain a mixed solution; A mixed slurry is obtained by adding alumina, cerium-zirconium oxygen storage material and rare earth oxide at a mass ratio of 10:5-20, wherein the total mass of the alumina, the cerium-zirconium oxygen storage material and the rare earth oxide is the same as the The mass ratio of deionized water is 1:9-5:5. 2) Using an acid to adjust the pH of the mixed slurry to 3-6, then ball-milling the mixed slurry for 0.5-2 hours, adding the active component, and then continuing to ball-mill for 0.5-2 hours to obtain a coating slurry; 3) using the coating slurry to vacuum coat the integral corrugated fiber paper carrier for 1-15 minutes, and purging the channels with vacuum to facilitate the uniform distribution of the coating slurry; 4) After coating the coating slurry on the integral corrugated fiber paper carrier, dry it under hot air at 60-200°C for 10-60min, and then bake it in air at 300-600°C for 1-8h, so as to obtain the integral Formula VOCs oxidation catalyst. 10. the preparation method of monolithic VOCs oxidation catalyst according to claim 9, is characterized in that, The binder in the step 1) is one or more of silica sol, aluminum sol, silica-alumina sol, titanium sol, aluminum dihydrogen phosphate and pseudo-boehmite, in terms of solids, the The amount of the binder added is 1-30wt% of the total mass of the alumina, the cerium-zirconium oxygen storage material and the rare earth oxide in the mixed slurry; The third auxiliary agent in the step 1) is polyvinyl alcohol, butylene glycol, polyethylene glycol, Tween-20, polyurethane, modified polyurethane, acrylate, modified polyacrylate, polyacrylate , polycarboxylate, organosiloxane, polyether-modified organosiloxane, polyester-modified organosiloxane, fatty alcohol polyoxyethylene ether and cellulose or one or more of them, the first The addition amount of the three additives is 0.1-10wt% of the total mass of the alumina, the cerium-zirconium oxygen storage material and the rare earth oxide in the mixed slurry; and The acid in the step 2) is one or more of nitric acid, hydrochloric acid, sulfuric acid, acetic acid, oxalic acid and citric acid.