The catalyst for the oxidation of sulfur compounds

 

(57) Abstract:

The invention relates to the production of heterogeneous catalysts for liquid-phase oxidation of sulfur compounds (sulfur dioxide, hydrogen sulfide, mercaptans) and can be used for purification of gas emissions and wastewater, energy, refining, petrochemical, chemical and pulp and paper industries. With the aim of increasing activity, mechanical strength and thermal stability of the catalyst serves a heterogeneous catalyst for the oxidation of sulfur compounds containing active component on the carrier, characterized in that as the active component contains pyrite cinder and pyrolusite-ore composition (mass fraction, %): manganese oxide (IV) 54,76 - 69,10; oxide of manganese (II) 1,80 - 4,85; iron oxide (III) 5,00 - 11,23; silicon oxide 4,05 - 7,52; barium oxide 3,95 - 5,02; aluminum oxide 0,92 - 5,03; titanium oxide 0,01 - 0,03; calcium oxide 0,50 - 0,82; magnesium oxide 0,40 - 0,70; potassium oxide 2,87 - 3,10; sodium oxide 0,37 - 0,58; oxide of phosphorus (V) 1,10 - 1,35; impurities - loss on ignition of the rest, as media - clay, and smoothly, in the following catalyst components (mass fraction,%): pyrite cinder 13 - 15; pyrolusite-ore 43 - 45; pleurobrachia relates to the production of heterogeneous catalysts for liquid-phase oxidation of sulfur compounds (sulfur dioxide, of hydrogen sulfide, mercaptans) and can be used for purification of gas emissions and wastewater, energy, refining, petrochemical, chemical and pulp and paper industries.

Known heterogeneous catalyst for purification of serosoderjaschei industrial waste gases by oxidation to sulfur dioxide hydrogen sulfide and organic sulfur compounds /1/. The main disadvantage of this catalyst is unsatisfactory, the depth of oxidation of hydrogen sulfide and organic sulfur compounds to sulfur dioxide. Sulfur dioxide is hard to recover highly toxic component. The cleaning gas from the sulfur dioxide is in itself no less a problem than purification from hydrogen sulfide and serverance.

The closest in technical essence and the achieved effect to the present invention is a catalyst for the oxidation of sulfur compounds, containing as an active ingredient the active sludge (35 to 50%) and medium-high density polyethylene (or polypropylene, polystyrene) /2/.

The specified catalyst-prototype differs relatively little activity in the process of liquid-phase oxidation of sulfur dioxide, and takagami catalyst.

The aim of the invention is to increase the total activity, mechanical strength and thermal stability of the catalyst.

This goal is achieved by the fact that the catalyst contains as active ingredients pyrite cinder and pyrolusite-ore composition (mass fraction)

Manganese oxide (IV) 54,76 69,10

Manganese oxide (II) 1,80 4,85

Iron oxide (III) 5,00 11,23

The silicon oxide 4,05 7,52

The barium oxide

3,95 5,02

Aluminum oxide

0,92 5,03

The titanium oxide 0,01 0,03

The titanium oxide 0,01 0,03

Calcium oxide 0,50 0,82

Magnesium oxide 0,40 0,70

The potassium oxide 2,87 3,10

The sodium oxide 0,37 0,58

The oxide of phosphorus (V) 1,10 1,35

impurities loss on ignition Else,

as a carrier of clay, which causes thermal resistance, and flux, which during sintering provides high mechanical strength of the granules. The components of the catalyst are contained in the following quantities (mass fraction):

Piraty cinder 13 15

Pyrolusite-ore 43 45

The flux 10 12

Clay The Rest.

Distinctive features of the proposed catalyst is that it contains as an active ingredient pyrite cinder and pyrolusite-ore; as a carrier of the strength of the granules of the catalyst, use the flux, which may be glass.

The proposed catalyst in comparison with the known possesses higher activity in the oxidation of sulfur compounds like hydrogen sulfide and mercaptans, and sulfur dioxide. Using the medium of clay, as well as the introduction of flux can significantly increase thermal resistance and mechanical strength of the granules of the catalyst and, therefore, prolong the service life of the catalyst 25 to 30% compared with the prototype.

Testing the activity of the catalyst in the process of absorption and catalytic purification of gases from sulfur dioxide was carried out in the reactor of continuous operation when the film mode of the process. Absorbent, which used water, was fed into the reactor from above, the gas backflow from the bottom. For experiments we used synthetic gas mixture containing sulphur dioxide 2000

2500 mg/m3and volume fraction of oxygen of 10% which roughly corresponds to their content in flue gases of power plants on brown coal. Sulfur dioxide was supplied from a cylinder, and the reduction of oxygen was carried out by dilution of the gas-air mixture with nitrogen.

The process of absorption citations of 0.14 m/s; the contact time of the gas-catalyst 3.6 sec; the ratio of the flow rate of the absorbent to the gas flow 0,00015; oxygen concentration in the gas 10% absorbent water with a pH of 6.5 - 7.5.

The catalyst activity was evaluated according to the degree of purification of the gas mixture from the sulfur dioxide, for this was determined by the concentration of sulfur dioxide in the gas mixture at the inlet and outlet of the oxidation reactor.

Catalytic oxidation of SO2to H2SO4in aqueous solutions is expressed by the following equation:

SO2+1/2O2+H2O H2SO4.

Additional controlled plant's effluent liquid-phase oxidation of SO2for completeness turning it into an H2SO4. The inspection results showed that when using the catalyst of the absorbed water SO4oxidized to sulfuric acid of not less than 96 99% versus 5 to 10% in the control experiment without catalyst.

Experiments to determine the activity of the catalyst in the process of liquid-phase oxidation of hydrogen sulfide and mercaptans oxygen were no real wastewater of pulp and paper production secondary condensate evaporation of black liquor with hydrogen sulfide 100 to 200 mg/DM3and methylmercaptan 60 80 mg/the arts: temperature 60oC; pressure 0.3 MPa; time of oxidation of 3 minutes, the feed rate of air 10 20 h-1the ratio (by weight) catalyst waste water was 1 to 5. The air in the reactor was carried out from the bottom using a special dispersant, provide good mass transfer.

The catalyst activity was evaluated according to the degree of oxidation of hydrogen sulfide and methylmercaptan in waste water, for this was determined by the concentration of H2S and mercaptan in the source and oxidative waste water. The definition of H2S and mercaptan was carried out by potentiometric method according to GOST 22985-88.

To assess the mechanical strength of the catalyst was determined by the strength of granules by crushing. High catalytic activity and mechanical strength of the proposed catalyst is observed at the specified mixing ratio of the active basis of the catalyst pyrite cinder and pyrolusite.

In addition, it is important to maintain the ratio of the mass media and the active principles in the composition of the catalyst. Thus, the increase in the mass fraction of the active substrate with the composition of the catalyst, more than 72% leads to decrease in mechanical strength of the granules of the catalyst, and reducing the mass fraction of active basis is>Pyrite cinder 15

Pyrolusite-ore 45

Glass 10

Clay 28

manufactured as follows.

Preparation of starting substances includes drying at 100 110oC for 4 h

The next operation of the mixing and grinding of components largely determines the end result of obtaining a catalyst having the necessary structure and phase composition. The mixing and grinding of all catalyst components are at the same time by a dry method in a ball mill for 8 hours or in a vibratory mill 30 minutes This allows to obtain material with a particle size of about 50 microns.

The mixture consisting of the active components, media and smoothly, granularit by the method of extrusion forming a pasty mass. The molding composition obtained by mixing the components of the catalyst shuts liquid, which is water. The mixing is carried out by a mechanical stirrer for 60 minutes, the Mass fraction of water in the moulding mass in the range of 38 to 42% depending on the individual properties of the mixture for each sample of the catalyst. Forming granules was carried out manually using a laboratory extruder with a screw auger with a capacity of 200 cm3

Drying extrusion was carried out at room temperature in air for 24 hours

Heat treatment was conducted in a laboratory electric muffle furnace under conditions of free access of air at the following temperature schedule:

temperature rise up to 500 530oC with a speed of 120oC for 60 min;

the extract at 500 530oC for 240 min;

exposure at 110oC for 15 min (the catalyst was transferred to a muffle heated to 1100oC without cooling);

the cooled within 4 hours

Example 2. The catalyst composition (mass fraction):

Pyrite cinder 13

Pyrolusite-ore 43

Glass 10

Clay 34

produced according to the method described in example 1.

Example 3. The catalyst composition (mass fraction):

Pyrite cinder 13

Pyrolusite-ore 45

Glass 10

Clay 32

produced according to the method described in example 1.

Example 4. The catalyst composition (mass fraction):

Pyrite cinder 15

Pyrolusite-ore 43

Glass 10

Clay 32

produced according to the method described in example 1.

Example 5. The catalyst composition (mass fraction):

Pyrite cinder 15

Pyrolusite-ore 45

2H2S and mercaptan according to the methods discussed above, as well as mechanical strength. The results are given in table. 1.

The test results showed that the introduction of the catalyst component in ratios of examples 1 to 5, i.e. in the ratio provided by the invention allows to obtain highly active catalysts with high mechanical strength.

The efficiency of absorption and catalytic gas purification from sulfur dioxide in the presence of the proposed catalyst is 96 to 97% against 41,5 catalyst for the prototype. The proposed activity of the catalyst during the oxidation of H2S is 97 98 and methylmercaptan 93 94% compared with 76.8% and 62.7 percent, respectively, for the prototype.

The proposed catalyst has good mechanical strength, the strength of granules separation is 4.2 4.6 kg/mm versus 3.1 kg/mm for the catalyst of the prototype. The strength of granules of catalyst directly determines its service life, which for the proposed catalyst 1,5 2,0 year depending on the conditions of the catalytic process against 1.0 - 1.5 years to catalyst-Eazzy catalyst (N 6 10) with education components, lying outside the bounds provided by the invention. The composition of the samples and the test results of their activity and mechanical strength are also presented in the table for comparison.

The test results of samples with vagrancy content components shows that the ratio of the mass fraction of pyrolusite to the mass fraction of pyrite cinder should be in the range of 1:(2,9 3,5), as provided by the invention. Changing this attitude, both towards increasing the share of pyrite cinder (sample 1), and towards increasing the share of pyrolusite-ore (sample 2), leads to a reduction in the overall activity of the catalyst.

The decrease in the mass fraction of the carrier in the catalyst below 28% (sample 3: the content of the carrier 26%), while maintaining the desired ratio of metal oxides in the composition of the active principles, leads to the reduction of the mechanical strength of the obtained sample. This entails rapid destruction of the catalyst in the catalytic reaction conditions and, therefore, reduction of service life. The increase in the mass fraction of the carrier above 34% (sample 4: the content of the carrier 36%) entails a reduction in the overall activity of the catalyst.

The decrease in the mass fraction of glass in the composition of the catalyst is less than 10% when testing samples of the catalyst vagrancy content components confirm the proposed composition of the catalyst is optimal.

The use of the catalyst in the industry will improve the efficiency of wastewater treatment and gas emissions, reduce the size of technological devices, to carry out the cleaning process in more mild conditions. All this makes it possible to reduce capital and operating costs during the implementation of the cleaning process using this catalyst. Furthermore, an additional advantage is the increased mechanical strength of the proposed catalyst, so the service life of the catalysts is increased by 25 to 30% compared with the prototype and is 1.5 to 2.0 years.

1. The catalyst for the oxidation of sulfur compounds containing active component on the carrier, characterized in that as the active component contains pyrite cinder and pyrolusite-ore composition, wt.share

Manganese oxide (IV) 54,76 69,10

Manganese oxide (II) 1,80 4,85

Iron oxide (III) 4,00 11,23

The silicon oxide 4,05 7,52

The oxide of barium 3,95 5,02

Aluminum oxide 0,92 5,03

The titanium oxide 0,01 0,03

Calcium oxide 0,50 0,82

Magnesium oxide 0,40 0,70

The potassium oxide 2,87 3,10

The sodium oxide 0,37 0,58

The oxide of phosphorus (V) abuses the content of the catalyst components, wt.share

Pyrite cinder 13 15

Pyrolusite-ore 43 45

The flux 10 12

Clay Rest

2. The catalyst p. 1, characterized in that the flux contains glass.

 

Same patents:
The invention relates to petrochemical synthesis, specifically to methods of producing N-methylaniline N-alkylation of aniline with methanol and can be used in the production of anti-knock additive to gasoline, in the manufacture of dyes and other products of organic synthesis

The invention relates to processes for the catalytic purification of hydrogen-containing gas from the oxygen-containing impurities, in particular carbon oxides, and to the technology of preparation of mixed catalysts and can be used in the chemical industry

The invention relates to processes for cleaning exhaust gases from the impurities of oxides of carbon, hydrocarbons, organic compounds using catalysts and can be used for the decontamination of exhaust gases of internal combustion engines, as well as in the chemical, gas and petrochemical industry

The invention relates to the production of catalysts, in particular nickelchromium catalysts for the hydrogenation of benzene
The invention relates to catalysts and methods of gas purification from nitrogen oxides by catalytic recovery flammable eyes and can be widely used in catalytic neutralization of exhaust gases of various industries
The invention relates to the production of monomers and can be used for the synthesis of polymer medical applications polydioxanone from which you get various products for surgery, absorbable in the tissues of a living organism, rezorbiruetsa suture thread

The invention relates to the production of catalysts for the dimerization and codimerization diene hydrocarbons

The invention relates to the production and use of catalysts used in obtaining sulfur from acid gases according to the method Claus, in particular to catalysts of the so-called protective layer serving to protect from oxygen catalysts of the base layer in the reactor installations Claus and the reactor tail gas treatment

The invention relates to the production of catalysts, namely the production of a catalyst for selective hydrogenation of unsaturated hydrocarbons

The invention relates to the production of catalysts for steam reforming of heavy hydrocarbon gases and liquid hydrocarbons including naphtha to produce hydrogen, azotobacteraceae mixture and process gases in the chemical and petrochemical industry

The invention relates to the production of catalysts for steam reforming of hydrocarbons, including naphtha and will be able to find its application for hydrogen, nitric mixture and process gases in the chemical and petrochemical industry

The invention relates to catalytic materials and can be used for ecological purposes for flue gas cleaning in industry and transport from carbon monoxide, nitrogen oxides and hydrocarbons

The invention relates to the production of catalysts for the processes of deep heterogeneous oxidation of organic compounds contained in the gas emissions of the production of synthetic rubbers

The invention relates to the production of graphite materials in the process of decomposition of methane and intended primarily for the preparation of ferromagnetic ink, graphite pigments to copy, synthetic carbon rubber and plastics

The invention relates to oxide type catalysts obtained on the basis of cobalt oxide, and can be used for oxidation of carbon monoxide

The invention relates to technology catalysts for the conversion of carbon monoxide to hydrogen and can be used in the chemical and refining industries

The invention relates to a method for producing a catalyst to remove oxygen in the processing technology for hydrogen sulfide gas in the sulfur method Claus
Up!