CN103691423A

CN103691423A - Preparation method for high-activity cellular nitrogen oxide removal catalyst

Info

Publication number: CN103691423A
Application number: CN201310620683.6A
Authority: CN
Inventors: 胡中光; 周刚; 王立鸿
Original assignee: HUBEI GUANGJING ENVIRONMENTAL PROTECTION CATALYSTS Co Ltd
Current assignee: HUBEI GUANGJING ENVIRONMENTAL PROTECTION CATALYSTS Co Ltd
Priority date: 2013-11-29
Filing date: 2013-11-29
Publication date: 2014-04-02

Abstract

The invention relates to the field of catalysts, and discloses a preparation method for a high-activity cellular nitrogen oxide removal catalyst. The preparation method is characterized by comprising the following steps: putting weighed TiO2 powder, SiO2, WO3 and V2O5 into a material mixing machine and stirring; adding a small amount of ammonia water and water in the process of stirring to adjust the PH value of the materials to be greater than 7; adding glass fiber and a trace amount of carboxymethyl cellulose, polyoxyethylene and sesbania powder, mixing by using a mixing machine to finally obtain a material which is suitable for extrusion molding, wherein the material mainly comprises the components of 68 to 92.8 percent of TiO2, 3 to 10 percent of SiO2, 2 to 10 percent of glass fiber, 2 to 10 percent of WO3, and 0.2 to 2 percent of V2O5. Due to the adoption of the technical scheme, the catalyst has the advantages of high mechanical strength, high wear-resistant strength, high temperature resistance, high activity and the like, can function under specific flue gas conditions, and can be widely applied to denitration devices such as low and high-dust thermal power plants.

Description

A kind of high activity honeycomb fashion removes the preparation method of nitrogen oxide catalyst

Technical field

The present invention relates to catalyst field, is the preparation method that a kind of high activity honeycomb fashion removes nitrogen oxide catalyst.

Background technology

Power plants nitrogen oxide generation accounts for 50% of national total release, and nitrogen oxide is the main reason that forms acid rain and photochemical fog in atmosphere, serious harm natural environment and human health.In September, 2011,21 Chinese Ministry of Environmental Protection issued < < fossil-fuel power plant atmospheric pollutant emission standard > >, and the concentration of emission limit value unification of domestic nitrogen oxide is defined as 100mg/m ³, the new-built unit time of implementation, the old unit time of implementation, this concentration of emission limit value required for national all regions from July, 2014 from 2012.Current, the mainstream technology of denitrating flue gas is SCR SCR technology in the world, and its core is SCR catalyst.

As far back as the seventies in last century, developed country just starts, according to situations such as national emission level, coal characteristics, boiler types, to have developed a series of SCR catalyst as Japan, Germany, the U.S. etc.At present, the experience of the many R&D institutions of China or individual foreign, complicated for Coal Combustion in China ature of coal, (for example flue-gas temperature is interval 360 ℃ ~ 450 ℃, and domestic coal-fired dustiness is up to 50-60g/Nm for the non-constant of boiler smoke condition after burning ³deng, flue gas NOx is up to 750mg) etc. situation, carry out the research of catalyst, and developed a series of denitrating catalysts.

Currently take the compositions such as TiO2 as main, V2O5 is denitrating catalyst active component.Simultaneously V2O5 is also the active component of SO2 oxidation side reaction, so the content of V2O5 is subject to the restriction of SO2 oxygenation efficiency, is not therefore increasing on the basis of V2O5 content, and adjusting formula, to improve catalyst activity will be the important breakthrough that catalyst is made.

Summary of the invention

The object of this invention is to provide and do not increasing on the basis of V2O5 content, adjust the preparation method that honeycomb fashion that formula improves catalyst activity removes nitrogen oxide catalyst, this catalyst is mainly with nano-TiO ₂for main component, add certain auxiliary agent and pore former and active component, thereby make this catalyst there is bimodal pore distribution structure.

Technical scheme of the present invention is: a kind of high activity honeycomb fashion removes the preparation method of nitrogen oxide catalyst, it is characterized in that making step is:

A by take TiO ₂powder, SiO ₂, WO ₃and V ₂o ₅put into batch mixer, stir; In whipping process, add a small amount of ammoniacal liquor and water, make the pH value of its material be greater than 7;

B adds carboxymethyl cellulose, polyethylene glycol oxide, the sesbania powder of glass fibre and trace, with batch mixer, mixes, and finally blends the material that is applicable to extrusion molding;

It is 150mm * 150mm that c extrudes sectional area with vacuum-extruder by above-mentioned material, and hole count is 18 * 18, the honeycomb fashion idiosome that length is 1000mm;

D is dried 7 ~ 15 days by idiosome under the condition of 30 ~ 70 ℃ of temperature, humidity 20 ~ 100%;

E calcines dried idiosome 8 ~ 15 hours under 250 ~ 300 ℃ of conditions, then under 380 ~ 420 ℃ of conditions, calcine 5 ~ 10 hours, finally under 580 ~ 620 ℃ of conditions, calcine 8 ~ 12 hours, thereby obtain a kind of highly active honeycomb fashion NO_x removal catalyst agent product.

Its main component TiO ₂content is 68 ~ 92.8%, SiO ₂content is 3%-10%, and content of glass fiber is 2%-10%, WO ₃content is 2% ~ 10%, V ₂o ₅content is 0.2% ~ 2%.

Owing to having adopted technique scheme, this catalyst mechanical strength is high, wear strength is strong, high temperature resistant, active advantages of higher.Can under specific flue gas condition, move, can extensively apply in the denitrification apparatus such as low, high dust thermal power plant.

The specific embodiment

Below in conjunction with embodiment, the present invention is further illustrated.

Embodiment 1

By the TiO of the 10Kg taking ₂the SiO of powder, 500g ₂, 0.4Kg WO ₃and the V of 70g ₂o ₅, put into batch mixer, stir; In whipping process, add a small amount of ammoniacal liquor and water, make the pH value of its material be greater than 7;

Add 0.5Kg glass fibre, 20g carboxymethyl cellulose, 30g polyethylene glycol oxide, 20g sesbania powder, with batch mixer, mix 2 ~ 4h, finally blend the material that is applicable to extrusion molding;

With vacuum-extruder, above-mentioned material being extruded to sectional area is 150mm * 150mm, and hole count is 20 * 20, the honeycomb fashion idiosome that length is 1000mm;

Idiosome is dried to 7 ~ 15 days under the condition of 30 ~ 70 ℃ of temperature, humidity 20 ~ 100%;

Dried idiosome is calcined 8 ~ 15 hours under 250 ~ 300 ℃ of conditions, then under 380 ~ 420 ℃ of conditions, calcined 5 ~ 10 hours, finally under 580 ~ 620 ℃ of conditions, calcine 8 ~ 12 hours, thereby obtain suitable catalyst.

Claims

1. high activity honeycomb fashion removes a preparation method for nitrogen oxide catalyst, it is characterized in that making step is:

2. a kind of high activity honeycomb fashion according to claim 1 removes the preparation method of nitrogen oxide catalyst, it is characterized in that its main component TiO ₂content is 68 ~ 92.8%, SiO ₂content is 3%-10%, and content of glass fiber is 2%-10%, WO ₃content is 2% ~ 10%, V ₂o ₅content is 0.2% ~ 2%.