CN102294244A

CN102294244A - Method for improving surface catalytic activities of catalyst particles

Info

Publication number: CN102294244A
Application number: CN2011101646703A
Authority: CN
Inventors: 金玲
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-06-17
Filing date: 2011-06-17
Publication date: 2011-12-28

Abstract

The invention discloses a method for improving surface catalytic activities of catalyst particles. The method mainly comprises: carrying out ultrafine crushing for the catalyst particles to substantially increase the specific surface area of the catalyst; then introducing a salt containing acid ions in a crushing chamber; crushing the salt, and mixing the salt with the catalyst, synchronously, decomposing the salt to form the acid ions through dual effects of the mechanochemical effect and the thermal-mechanical effect; automatically coating the acid ions on the surface of the ultrafine crushed catalyst particles in the crushing chamber to form acid sites with the catalytic activities so as to substantially improve the catalytic activity of the catalyst.

Description

A kind of method that improves catalyst granules surface catalysis activity

Technical field

The invention belongs to the preparation field of ultra-fine new material, be specifically related to a kind of preparation method of ultra-fine high activated catalyst.The acid sites of catalyst surface, no matter be L acid or B acid, they all are very important to the catalytic activity of catalyst.Therefore taking the advanced technology of science to increase the acid sites position of catalyst surface, is a kind of efficient ways that improves catalyst granules surface catalysis activity.

Background technology

As everyone knows, in the catalytic reactions such as the catalytic pyrolysis in petroleum refining, isomerization, alkylation, aromatisation and disproportionation, all adopt alundum (Al, alumina silicate, molecular sieve etc. as catalyst (or catalyst carrier).These non-metal kind materials discover that with modern means of science and technology its particle surface all exists Bronsted acid (B acid) or aprotic acid (L acid) class acid sites position.Why they have catalytic activity, and the Industrial Catalysis reaction is realized in these acid sites positions that depend on particle surface exactly.For research surface of solids acid sites position, developed a lot of methods, wherein infra-red sepectrometry is separated and can be determined its acid strength in qualitative B acid or L acid.Nowadays, the surface texture that the Chemical Engineer can design catalyst according to the requirement and the function of catalyst, and preparation catalyst.But because preparation process all belongs to traditional chemical production processes, therefore produce serious environmental inevitably and pollute, simultaneously, form disappearance, the inefficacy in use of acid sites position easily.Therefore relevant department wishes that the scientific worker is studied improvement, and a kind of pollution-free, highly active Preparation of catalysts method is provided, to promote the technological progress of Preparation of Catalyst industry.

Summary of the invention

The object of the present invention is to provide " a kind of method that improves catalyst granules surface catalysis activity ", it had both overcome the pollution in traditional chemical production catalyst process, increase substantially the catalytic activity on catalyst granules surface again, belonged to a kind of pollution-free, highly active Preparation of catalysts method.

Design of the present invention is such:

At first existing catalyst is carried out ultra-fine grinding, when improving the catalyst specific surface, eliminate the agglomeration of powder (or particle); Then catalyst is the required salt compounds that contains acid ion is introduced in the crushing chamber; in ultra-fine grinding and catalyst granules mixing; make this salt compounds resolve into the acids ion with mechanical force and chemical and thermodynamic (al) double action; and be implanted in the surface of catalyst granules automatically, thereby produce highly active catalyst.

According to above-mentioned design, the present invention also is achieved in that

At first place size reduction machinery to carry out super-fine processing catalyst granules, make ultra-fineization of particle, thereby increase substantially the catalysis specific surface of catalyst; The salt compounds that contains acid ion (i.e. the labile salt compounds of a class) that will contain the catalyst needs is then inserted in the pulverizer, makes its pulverizing on the one hand, mixes with the catalyst ultra-fine grain simultaneously; This salt compounds that contains acid ion is broken down into acid ion under the double action of mechanical force and chemical and suitable temperature (thermodynamics) on the other hand, and another alkali ion group, wherein said acid ion then is coated on the surface of (or being implanted in) catalyst granules automatically.Why the acid ion material can be implanted in the surface of catalyst granules automatically, this be since the catalyst granules surface by ultra-fine grinding after, its surface free energy increases substantially, after the acid ion material is coated on the catalyst granules surface, can reduce the catalyst granules surface free energy effectively, be very stable so be implanted with or coated the catalyst of acid ion material; Then add an amount of surface-active dispersant, prevent the reunion of the catalyst granules (or claiming powder) of ultra-fine grinding, finally obtain a class high activity industrial catalyst.

Above-mentioned said catalyst is a class nonmetal oxide class catalyst, comprises Al ₂O ₃, SiO ₂, TiO ₂(or nanometer Al ₂O ₃, SiO ₂, TiO ₂), Fe ₂O ₃Deng and the natural mineral matter powder, as talcum powder, kaolin, butter soil, zeolite, silicic acid alum clay etc.; Saidly contain the salt compounds that catalyst needs acid ion, mean the salt of the labile strong acid weak base class of a class, they can resolve into acid ion under the effect of certain temperature and mechanical force, salt compounds commonly used comprises a kind of in ammonium phosphate, ammonium sulfate, the ammonium nitrate class or their mixture; Said surface dispersant comprises with the Si ion being a cationoid type surfactant of representative or being a kind of among the class neutral surface active agent of representative or their mixture with Si and Al ion that its consumption is 0.2～0.5% (wt) of catalyst weight; Said proper temperature means than the temperature that contains low 20～80 ℃ of acid ion salt compounds critical heat decomposition temperature, because these salt compounds that contain acid ion are under mechanical force and chemical and thermodynamics double action, need not to reach acid ion salt compounds critical heat decomposition temperature, just decomposed; Said pulverizer comprises a kind of in mixer, ball mill, vibrating pulverizer and the airslide disintegrating mill.

Point out in passing, contain the salt compounds of acid ion, after its another alkali ion group that decomposites is drawn, absorb the branch device by follow-up water and recycled, thereby can guarantee no longer to cause in the industrial processes environmental pollution.

The specific embodiment

Further illustrate content of the present invention below in conjunction with implementing, but these embodiment do not limit protection scope of the present invention.

Embodiment 1

The ferric oxide powder of modification (or its particle diameter of particle≤1 μ m) Preparation of catalysts.In the production technology of DCL/Direct coal liquefaction, adopt di-iron trioxide (Fe ₂O ₃) make catalyst.Take by weighing 1000 gram ferric oxide powders (particle diameter 〉=45 μ m), adopt the consersion unit of vibrating pulverizer tool as mechanical force and chemical.Earlier the di-iron trioxide body is placed vibrating pulverizer, vibration was pulverized 5 minutes at least, did ultra-fine grinding and handled.Taking-up is placed in the blender, and the ammonium phosphate that adds 5% (wt%) earlier mixes; After adding 0.3% (wt%) polyethylene glycol dispersant again and being mixed, again move in the vibrating pulverizer, then under 60 ℃ of thermal environments, vibrate at least and pulverized 10 minutes, decomposing the ammonium ion formation ammonia molecule that produces in the crushing process is recycled with air-flow introducing absorption plant, the acid ion that decompose to produce coats the surface of (or plant in) ferric oxide particle automatically, form the acidic catalyst point, obtain a kind of surface and contain phosphoric acid acid point position di-iron trioxide catalyst prod.Compare with original single ferric oxide particle (or powder) catalyst, because the acidic catalyst point increases, its catalyst activity is carried one times at least.

Embodiment 2

Ultra-fine alundum (Al (the Al of modification ₂O ₃) Preparation of catalysts.

In the oil refining cracking reaction, often adopt Al ₂O ₃Make catalyst.Adopt phosphoric acid or sulfuric acid to do the surface acidity modification simultaneously and improve activity of such catalysts.Promptly when using this catalyst, with phosphoric acid and Al ₂O ₃Catalyst directly mixes, refining, extrusion molding.But the catalyst of Chu Liing in this way, its stability is not high, and activity also very easily descends, and is perplexing branch of industry for a long time always.The method that the present invention adopts mechanical force and chemical and thermodynamics to combine is carried out modification, promptly adopts the air-flow disintegrating apparatus to Al ₂O ₃Catalyst carries out ultra-fine grinding earlier, imports ammonium phosphate and surface dispersant polyphosphate sodium then, and air-flow is pulverized temperature is controlled at 80 ℃, makes ammonium phosphate decomposite phosphate ion and plants automatically in (or coating) at catalyst granules (Al ₂O ₃) the surface.Because preparation method of the present invention is based under the catalyst operating mode that surface free energy increases substantially in the ultra-fine grinding process; automatically be coated on catalyst granules when surface when decompositing phosphate anion; because the effect of the surface free energy of catalyst granules; catalyst granules is understood automatically and acid ion attracts each other; form metastable structure; so the catalyst that obtained is the catalytic stability height not only, and its catalytic activity improves more than 20% at least than the catalytic activity of direct doping gained catalyst.

Embodiment 3

The preparation of the molecular sieve catalysts of modification.

Molecular sieve catalyst commonly used adopts phosphoric acid and an amount of niobium hydroxide to do modification usually and handles, and is used for removing the alkylation reaction of aromatic hydrocarbons trace amounts of olefin.Concrete operations systems takes by weighing molecular sieve after ion-exchange by different proportion, and adds Nb (OH) ₅, extruded moulding again after being mixed earlier, 110 ℃ of oven dry down, 550 ℃ of following roastings 3 hours are pulverized, are sieved after cooling off naturally, obtain 20～40 order particles and make catalyst.Adopt method of the present invention then by the identical step of embodiment 1, in vibrating pulverizer, once finish Nb (OH) ₅Modification to molecular sieve.Detect and actual the use through experiment, use method of the present invention, its catalytic activity of gained catalyst improves more than 20% than prior art gained activity of such catalysts at least.

Claims

1. method that improves catalyst granules surface catalysis activity, it is as follows to it is characterized in that this method comprises:

(1) at first catalyst granules is carried out ultra-fine grinding, thereby significantly improve the catalysis specific surface of catalyst granules;

(2) salt compounds that will contain acid ion is then introduced in the crushing chamber, under the effect of crush force, with the abundant mixing of the catalyst granules of ultra-fine grinding, simultaneously under mechanical force and chemical and thermodynamics double action, impel aforesaid salt compounds to decompose, form acid ion, and automatically be coated on the surface of catalyst granules, become the catalysis acid sites of catalyst surface;

(3) add an amount of surface dispersant then, prevent the reunion of (or claiming powder) of above-mentioned catalyst granules, thereby obtain a kind of highly active catalyst.

2. the method for claim 1, wherein said catalyst is a kind of nonmetal oxide class catalyst, comprises Al ₂O ₃, SiO ₂, TiO ₂And the natural mineral matter powder, as talcum powder, kaolin, butter soil, zeolite, silicic acid alum clay etc.

3. the method for claim 1, the wherein said salt compounds that contains acid ion, mean the salt of a class strong acid weak base class, they can decomposite acid ion under the effect of certain temperature and mechanical force and chemical, be specially a kind of in ammonium phosphate, ammonium sulfate, the ammonium nitrate or their mixture.

4. the method for claim 1, wherein said surface dispersant, comprise with the Si ion and be a cationoid type surfactant of representative, be a kind of among the class neutral surface active agent of representative or their mixture with Si and Al ion that its consumption is 0.2～0.5% (wt) of catalyst weight.

5. the method for claim 1, wherein said thermodynamics means the temperature of the salt compounds thermal decomposition that contains acid ion, it is usually than low 20～80 ℃ of the critical heat decomposition temperature of normal salt compounds of the same race.

6. the method for claim 1, wherein said mechanical force and chemical means that the mechanical force of the size reduction machinery that a class is commonly used, concrete pulverizer comprise and stirs a kind of in mill, ball mill, vibrating pulverizer and the airslide disintegrating mill, effect by mechanical force, the critical heat decomposition temperature of above-mentioned salt compounds is reduced, and change into the chemical breakdown effect.