CN101559367A - Integrated absorbent and catalyzer for removing SO2and NOx and preparation method thereof - Google Patents

Abstract

The invention discloses an integrated absorbent and catalyzer for removing SO2 and NOx and a preparation method thereof. In the preparation method, gamma-Al2O3 with strong absorbability and catalytic activity are mainly adopted as a desulfurizer carrier and CuO/gamma-Al2O3 absorbent/activator with different components is prepared by an equal volume dipping method. The desulfurizer has good effect of removing SO2 and NOx, thereby the defect that the performance of the desulfurizer on the current market is single is solved, and the SO2 and the NOx in smoke can be removed simultaneously. The invention has a significance for simplifying desulphurisation devices of electric power plants and reducing investment of the desulphurisation devices, and the catalyzer has good regeneration performance, low production cost, simple process and good application prospect.

Description

A kind of SO that removes 2Integrated absorbent and Catalysts and its preparation method with NOx

Technical field:

The invention belongs to the coal combustion technology field, be specifically related to purify the technology of toxic gas in the coal combustion exhaust, further is a kind of SO of removing ₂With NO _xIntegrated absorbent and Catalysts and its preparation method.

Background technology:

In recent years, along with the fast development of industry, problem of environmental pollution is also more and more outstanding, enters atmosphere as the sulfur dioxide in the burnt gas such as oil, coal, oxynitrides etc., causes the severe contamination of atmospheric environment.According to statistics, the acid rain area coverage of China reaches more than 40% at present, thereby control SO ₂Discharging, conserving natural habitats in China is instant problem.

Coal-burning boiler configuration flue gas desulfur device is still present reduction SO ₂Discharging is one of the most effective approach.The most ripe flue gas desulfurization of present stage is the limestone/gypsum method of dry type or wet type, but investment that it is high and operating cost and the great amount of water resources that is consumed become the bottleneck that this technology is applied in China, in addition, another that calcium-based desulfurization brought the comparatively problem of difficulty is to produce a large amount of discarded objects, forms secondary pollution.Spray drying process and sorbent injection method (stove in or flue) produce easy-to-handle dried discarded object with it, and the advantage economized of investment obtains application to a certain degree, but have the lower problem of desulfurization degree (being generally about 80%).

Since in the flue gas except SO ₂The outer NO that also has a great deal of _x, therefore exploitation can be controlled SO simultaneously ₂With NO _xThe technology of polluting has great application prospect.Present SO ₂/ NO _xAssociating removing process majority is in the research and development stage, only in some, the power plant of low-sulfur coal obtains commercial the application, mainly contain: solid absorption/method of reproduction, gas-solid catalysis method, electronic beam method, impulse electric corona plasma method etc.

Existing absorbent and catalyst mainly are to SO ₂And NO _xCarry out catalytic oxidation, make it at high temperature convert material in Sulfates or the nitrate to, remove SO thereby reach ₂And NO _xPurpose Deng toxic gas.Mainly adopt now CuO/ γ-Al ₂O ₃The desulphurization denitration technology, but its commercialization popularization and application still has a segment distance; How with CuO/ γ-Al ₂O ₃The desulphurization denitration technology is carried out quantitatively, is described exactly, and the problem that exists in actual motion to solve this technology makes it to be applied to production practices, is one of problem that faces at present.

Summary of the invention:

For this reason, the object of the present invention is to provide a kind of SO of removing ₂With NO _xIntegrated absorbent and Catalysts and its preparation method.

For achieving the above object, the present invention adopts technical scheme as follows:

A kind of SO that removes ₂With NO _xIntegrated absorbent and catalyst, take weight component below unit comprises: Al ₂O ₃78.5～97.5 parts, Cu (NO ₃) ₂2.5～20 parts, 0～1.5 part of co-catalyst.

Described Al ₂O ₃For being preferably γ-Al ₂O ₃

Described co-catalyst is the binary composite metal salt.

Described co-catalyst is Zn (NO ₃) ₂

A kind of SO that removes ₂With NO _xIntegrated absorbent and Preparation of catalysts method, specifically comprise step:

(1) gets 97.5 parts Al ₂O ₃Powder preparation becomes the BET surface area at 225m ²/ g, BJH absorption pore volume is 0.49ml/g, and bulk density is 0.73g/ml, and particle diameter is the microballoon about 20 orders;

(2) will impregnated in the Cu (NO that contains 2.5 parts after the above-mentioned microballoon activation ₃) ₂Kept 40 minutes in the equal-volume solution;

(3) above-mentioned solution is heated to 150 ℃, and dry 12 hours, dried thick catalyst obtained;

(4) the thick catalyst that drying is good was 500 ℃ of lower calcinings 5 hours, and cooling has namely obtained required desulfurizing agent.

A kind of SO that removes ₂With NO _xIntegrated absorbent and Preparation of catalysts method, specifically comprise step:

(1) gets 85 parts Al ₂O ₃Powder preparation becomes the BET surface area at 295m ²/ g, BJH absorption pore volume is 0.64ml/g, and bulk density is 0.47g/ml, and particle diameter is the microballoon about 30 orders;

(2) will impregnated in the Cu (NO that contains 14 parts after the above-mentioned microballoon activation ₃) ₂With 1 part of Zn (NO ₃) ₂Mixing equal-volume solution in kept 50 minutes;

(3) above-mentioned solution is heated to 150 ℃, and dry 10 hours, dried thick catalyst obtained;

(4) the thick catalyst that drying is good was 600 ℃ of lower calcinings 7 hours, and cooling has namely obtained required desulfurizing agent.

A kind of SO that removes ₂With NO _xIntegrated absorbent and Preparation of catalysts method, specifically comprise step:

(1) gets 78.5 parts Al ₂O ₃Powder preparation becomes the BET surface area at 205m ²/ g, BJH absorption pore volume is 0.54ml/g, and bulk density is 0.69g/ml, and particle diameter is the microballoon about 30 orders;

(2) will impregnated in the Cu (NO that contains 20 parts after the above-mentioned microballoon activation ₃) ₂With 1.5 parts of Zn (NO ₃) ₂Mix in the equal-volume solution and kept 60 minutes;

(3) above-mentioned solution is heated to 130 ℃, and dry 11 hours, dried thick catalyst obtained;

(4) the thick catalyst that drying is good was 500 ℃ of lower calcinings 8 hours, and cooling has namely obtained required desulfurizing agent.

The present invention adopts porous, high-specific surface area, and has the γ-Al of strong absorption affinity and catalytic activity ₂O ₃As the desulfurizing agent carrier, prepared the CuO/ γ-Al of different component by the incipient impregnation method ₂O ₃Absorption/catalyst, this desulfurizing agent not only have the good SO that removes ₂Effect, and to NO _xGood removal effect is also arranged, thereby solved the in the market single shortcoming of desulfurizing agent performance, adopt CuO/ γ-Al ₂O ₃As removing SO ₂With NO _xIntegrated absorption/catalyst, can remove simultaneously the SO in the flue gas ₂With NO _x, for the desulphurization plant of simplifying power plant, the investment that reduces desulphurization plant is significant, and this catalyst regeneration performance is good, and production cost is low, and technological process is simple, has a good application prospect.

The specific embodiment:

Core concept of the present invention is: it adopts reproducible CuO/ γ-Al ₂O ₃As removing SO ₂With NO _xIntegrated absorbent and catalyst, utilize to be carried on porous carrier γ-Al ₂O ₃On CuO and the SO in the flue gas ₂And O ₂Reaction generates CuSO ₄To reach the desulfurization purpose, at NH ₃And O ₂Under the condition that exists, CuO, CuSO ₄Can be used as again catalyzing N O _xBe reduced to N ₂Catalyst; When absorbent absorbs SO ₂When reaching capacity, can utilize CH ₄, H ₂Deng with its reducing/regenerating, obtain the SO of higher concentration ₂And Cu, SO ₂Can further be processed into sulfuric acid, sulphur and liquid SO through reclaiming ₂Deng, Cu runs into O free in the flue gas ₂Generating again CuO reuses.

The present invention is to have the γ-Al of strong absorption affinity and catalytic activity ₂O ₃As the desulfurizing agent carrier, it is carried out molding, granulating, and be prepared into 20～50 purpose microballoons, the BET surface area of this microballoon is at 200～300m ²/ g, BJH absorption pore volume is 0.45～0.65ml/g, bulk density is 0.60～0.75g/ml; With the Al for preparing ₂O ₃Microballoon activates in advance, impregnated in then Cu (NO ₃) ₂With in corresponding metal chloride or the nitrate solution 20～60 minutes, so 80～50 ℃ lower dry 10～15 hours, prepare the CuO/ γ-Al of different component ₂O ₃Absorption/catalyst, thus reach the SO that removes simultaneously in the flue gas ₂With NO _xPurpose.

For setting forth thought of the present invention and purpose, the present invention is described in further details below in conjunction with specific embodiment.

The SO that removes of the present invention ₂With NO _xIntegrated absorbent and catalyst, take weight component below unit mainly includes: Al ₂O ₃78.5～97.5 parts, Cu (NO ₃) ₂2.5～20 parts, 0～1.5 part of co-catalyst.

Wherein, described Al ₂O ₃Include α-Al ₂O ₃, β-Al ₂O ₃, γ-Al ₂O ₃, θ-Al ₂O ₃, δ-Al ₂O ₃, η-Al ₂O ₃, ρ-Al ₂O ₃, κ-Al ₂O ₃Deng 8 kinds of forms, the Al here ₂O ₃Can be any one or several combining forms in above-mentioned 8 kinds of forms, and because γ-Al ₂O ₃Have strong absorption affinity and catalytic activity, can do adsorbent and catalyst, therefore preferred γ-Al ₂O ₃Be carrier material.

And above-mentioned co-catalyst can be alkali and rare earth metal (such as Na, K, Ca, Sr, Ba); Rare earth element (such as La, Ce); The slaine (any one among employing metal K, Ca, Sr, Ce, Cr, the Fe prepares jointly with sodium salt) that transition metal (such as V, Cr, Fe, Co, Ni, Zn) or binary are compound wherein is preferably binary composite metal salt Zn (NO ₃) ₂

Preferred embodiment one, a kind of SO that removes ₂With NO _xIntegrated absorbent and Preparation of catalysts method, specifically comprise step:

(1) gets 97.5 parts Al ₂O ₃Powder preparation becomes the BET surface area at 225m ²/ g, BJH absorption pore volume is 0.49ml/g, and bulk density is 0.73g/ml, and particle diameter is the microballoon about 20 orders;

Here the BET surface area refers to the total external surface area sum of all particles in every gram material, and it can be detected by special instrument, and carries out data according to the BET theory and process.

(2) will impregnated in the Cu (NO that contains 2.5 parts after the above-mentioned microballoon activation ₃) ₂Kept 40 minutes in the equal-volume solution;

(3) above-mentioned solution is heated to 150 ℃, and dry 12 hours, dried thick catalyst obtained;

(4) the thick catalyst that drying is good was 500 ℃ of lower calcinings 5 hours, and cooling has namely obtained required desulfurizing agent.

Preferred embodiment two, a kind of SO that removes ₂With NO _xIntegrated absorbent and Preparation of catalysts method, specifically comprise step:

(1) gets 85 parts Al ₂O ₃Powder preparation becomes the BET surface area at 295m ²/ g, BJH absorption pore volume is 0.64ml/g, and bulk density is 0.47g/ml, and particle diameter is the microballoon about 30 orders;

(2) will impregnated in the Cu (NO that contains 14 parts after the above-mentioned microballoon activation ₃) ₂With 1 part of Zn (NO ₃) ₂Mixing equal-volume solution in kept 50 minutes;

(3) above-mentioned solution is heated to 150 ℃, and dry 10 hours, dried thick catalyst obtained;

(4) the thick catalyst that drying is good was 600 ℃ of lower calcinings 7 hours, and cooling has namely obtained required desulfurizing agent.

Preferred embodiment three, a kind of SO that removes ₂With NO _xIntegrated absorbent and Preparation of catalysts method, specifically comprise step:

(1) gets 78.5 parts Al ₂O ₃Powder preparation becomes the BET surface area at 205m ²/ g, BJH absorption pore volume is 0.54ml/g, and bulk density is 0.69g/ml, and particle diameter is the microballoon about 30 orders;

(2) will impregnated in the Cu (NO that contains 20 parts after the above-mentioned microballoon activation ₃) ₂With 1.5 parts of Zn (NO ₃) ₂Mix in the equal-volume solution and kept 60 minutes;

(3) above-mentioned solution is heated to 130 ℃, and dry 11 hours, dried thick catalyst obtained;

(4) the thick catalyst that drying is good was 500 ℃ of lower calcinings 8 hours, and cooling has namely obtained required desulfurizing agent.

More than to a kind of SO that removes provided by the present invention ₂With NO _xIntegrated absorbent and Catalysts and its preparation method be described in detail, used specific case herein principle of the present invention and embodiment are set forth, the explanation of above embodiment just is used for helping to understand method of the present invention and core concept thereof; Simultaneously, for one of ordinary skill in the art, according to thought of the present invention, the part that all can change in specific embodiments and applications, in sum, this description should not be construed as limitation of the present invention.

Claims (7)

1, a kind of SO that removes ₂With NO _xIntegrated absorbent and catalyst, it is characterized in that take weight component below unit comprises: Al ₂O ₃78.5～97.5 parts, Cu (NO ₃) ₂2.5～20 parts, 0～1.5 part of co-catalyst.

2, the SO that removes according to claim 1 ₂With NO _xIntegrated absorbent and catalyst, it is characterized in that described Al ₂O ₃For being preferably γ-Al ₂O ₃

3, the SO that removes according to claim 1 ₂With NO _xIntegrated absorbent and catalyst, it is characterized in that described co-catalyst is the binary composite metal salt.

4, the SO that removes according to claim 3 ₂With NO _xIntegrated absorbent and catalyst, it is characterized in that described co-catalyst is Zn (NO ₃) ₂

5, a kind of SO that removes ₂With NO _xIntegrated absorbent and Preparation of catalysts method, it is characterized in that specifically comprising step:

(1) gets 97.5 parts Al ₂O ₃Powder preparation becomes the BET surface area at 225m ²/ g, BJH absorption pore volume is 0.49ml/g, and bulk density is 0.73g/ml, and particle diameter is the microballoon about 20 orders;

(2) will impregnated in the Cu (NO that contains 2.5 parts after the above-mentioned microballoon activation ₃) ₂Kept 40 minutes in the equal-volume solution;

(3) above-mentioned solution is heated to 150 ℃, and dry 12 hours, dried thick catalyst obtained;

(4) the thick catalyst that drying is good was 500 ℃ of lower calcinings 5 hours, and cooling has namely obtained required desulfurizing agent.

6, a kind of SO that removes ₂With NO _xIntegrated absorbent and Preparation of catalysts method, it is characterized in that specifically comprising step:

(1) gets 85 parts Al ₂O ₃Powder preparation becomes the BET surface area at 295m ²/ g, BJH absorption pore volume is 0.64ml/g, and bulk density is 0.47g/ml, and particle diameter is the microballoon about 30 orders;

(2) will impregnated in the Cu (NO that contains 14 parts after the above-mentioned microballoon activation ₃) ₂With 1 part of Zn (NO ₃) ₂Mixing equal-volume solution in kept 50 minutes;

(3) above-mentioned solution is heated to 150 ℃, and dry 10 hours, dried thick catalyst obtained;

(4) the thick catalyst that drying is good was 600 ℃ of lower calcinings 7 hours, and cooling has namely obtained required desulfurizing agent.

7, a kind of SO that removes ₂With NO _xIntegrated absorbent and Preparation of catalysts method, it is characterized in that specifically comprising step:

(1) gets 78.5 parts Al ₂O ₃Powder preparation becomes the BET surface area at 205m ²/ g, BJH absorption pore volume is 0.54ml/g, and bulk density is 0.69g/ml, and particle diameter is the microballoon about 30 orders;

(2) will impregnated in the Cu (NO that contains 20 parts after the above-mentioned microballoon activation ₃) ₂With 1.5 parts of Zn (NO ₃) ₂Mix in the equal-volume solution and kept 60 minutes;

(3) above-mentioned solution is heated to 130 ℃, and dry 11 hours, dried thick catalyst obtained;

(4) the thick catalyst that drying is good was 500 ℃ of lower calcinings 8 hours, and cooling has namely obtained required desulfurizing agent.