Method of activating carbon monoxide oxidation catalyst
FIELD: oxidation catalysts.
SUBSTANCE: invention relates to sorption engineering and can be used for regeneration of different kinds of hopcalite lost catalytic activity during long-time storage. Regenerated sorbents can be used un respiratory masks and in processes or removing carbon monoxide from industrial emissions. Invention provides a method for activating carbon monoxide oxidation catalyst involving heat treatment thereof and characterized by that activation is conducted by heating catalyst bed 2-3 cm thick to 180-380°C at temperature rise velocity 10-20°C/min while constantly carrying away reactivation products.
EFFECT: enabled restoration of catalytic activity.
The invention relates to the field of sorption techniques, namely the clean air mixtures of carbon monoxide and can be used for regeneration of different types of catalyst for the oxidation of carbon monoxide (hopcalite), have lost their catalytic activity during long-term storage.
The regenerated sorbent can be used in methods of respiratory protection and purification of industrial emissions of carbon monoxide.
There are different ways of activation of hopcalite, for example, by heat treatment at 550-850°WITH (EN 2063803, 20.07.96) or drying gas-air mixture when the temperature increases from 40-75 up to 150-250°WITH (EN 2035997, 27.05.96).
Using the known activation method does not lead to full recovery of hopcalite.
The closest in technical essence and the achieved results is an activation method of hopcalite by heat treatment of the layer at t=120-320°C, a pressure of 200-400 kg/m2, gas mixture composition, vol.%:
WITH not more than 0.01;
Nitrogen and inert gases - leave
The disadvantage of the prototype is the impossibility of full recovery of the initial activity of the catalyst after long-term storage and stability of its activity through air purification.
The invention which is the recovery of the initial activity of the catalyst for oxidation of carbon monoxide after a long storage period.
The problem is solved by the proposed method activation catalyst for the oxidation of carbon monoxide by thermal processing, and activation of the catalyst is lead by heating the catalyst layer thickness of 2-3 cm to 180-380°With the speed of temperature rise 10-20°/min at a constant tap of products of reactivation.
Of scientific and technical literature the authors do not know the method of activation of the catalyst for oxidation of carbon monoxide by heating the layer thickness of 2-3 cm with speed of temperature rise 10-20°/min
The essence of the method consists in the following.
The catalyst for the oxidation of carbon monoxide (hopcalite) is a mixture of active oxides of copper and manganese. During long-term storage hopcalite well absorbs moisture from the air, thus there is the hydration of the active centers (manganese dioxide) with the formation of crystalline hydrates, which shield the active centers, thereby making it difficult to access carbon monoxide to them and reducing the efficiency of the catalyst as a whole. The process of oxidation WITH oxygen occurs on MnO2who is restored to MnO, and then MnO again oxidized to MnO2resulting in the alternate oxidation and reduction of the catalyst surface at high speed this process provides is raised by the presence of oxygen centers on the surface of hopcalite.
Thus the activation process hopcalite needed so that with one hand - held deep dehydration of the active centers, which occurs at t°>180°and on the other you want to save the saturation of the active surface oxygen, which is provided with a stationary process with constant removal of the reaction products.
As a result of numerous experiments were able to optimize the parameters of the activation process, which allows you to restore the catalyst activity. Empirically set temperature range of the heat treatment, the speed of temperature rise and the thickness of the catalyst layer.
The method is as follows.
Take the inactive catalyst for the oxidation of carbon monoxide, wet during storage to a moisture content of 3-25%, load it in a pan with a layer of 2-3 cm and placed in a chamber (stationary) furnace exhaust products vacuum or by fans. Turn up the heat with a speed of 10-20°/min to t=180-380°C, maintain the product at this temperature for 1-5 hours to produce mixing of the catalyst and the vacuum or suction fan reaction products. The process is carried out to obtain a catalyst with moisture content less than 1.0%. Next, the finished product is unloaded in a sealed container and analyzer the Ute to the dynamic activity of the carbon monoxide.
Take 250 kg of inactive catalyst with dynamic activity 10 min (initial activity 46 min), moisture 8%, and load in pallets of 50 kg, the thickness of the product layer thickness is 2.0 cm, placed in a drying chamber furnace, equipped with exhaust ventilation, and turn up the heat with a speed of 10°/min to t=180°C, maintain the catalyst at this temperature for 5 hours, stir every 15-20 minutes Continuously running exhaust ventilation allows removal of reaction products from the working zone of the furnace. The finished product with a moisture content of 0.5% unload in sealed steel drums, cool and carry out tests on the dynamic activity of the carbon monoxide. The estimation of the dynamic activity of the catalyst is carried out on a dynamic device DP-2, the test conditions are the following:
the concentration of carbon monoxide to 6.2+/-0,3 mg/l;
- layer height - 2.5 cm;
- specific flow rate of the gas mixture of 0.32+/-0,01 DM3rpm·cm2;
the absolute humidity of the gas mixture of 8.6+/-0,3 mg/l;
the temperature at test 23+/-5°C.
The resulting catalyst had a dynamic activity 46 minutes
Take 300 kg of inactive catalyst with dynamic activity 15 min (initial activity 48 min), moisture 6%, and load the pallets 60 kg, the thickness of the layer about the ukta is 3.0, see Next, the process is conducted as in example 1 except that the heating include speeds of 15°/min up to t=250°C and the product can withstand 4 hours.
The resulting catalyst had a dynamic activity 48 minutes
Take 300 kg of inactive catalyst with dynamic activity 8 min (initial activity 45 min), moisture 10%, loaded onto pallets and lead the process as in example 2 except that the heating lead with the speed of 20°/min to t=380°C and the product is kept in a furnace for 3 hours.
The resulting catalyst had a dynamic activity 46 minutes
Empirically chosen and the optimal modes of activation, the choice of the main parameters of the following reason. At a temperature of less than 180°unable to carry out the dehydration oxygen centers, and when t>380°the process of recovery of active Mn+4to inactive Mn+2. The thickness of the catalyst layer during the heat treatment is chosen in such a way as to achieve an optimal balance between the process of removing water from the surface of the grains of the catalyst and removal of products from the working area of termoaparata. The speed of temperature rise within 10-20°/min ensures a gradual and uniform heating of the catalyst layer, as heating with a higher speed at high humidity catalyst (8-25%) is riodic to intensive allocation of water vapor in the beginning of the process, and heating with a rate of less than 10°/min economically feasible.
The proposed method allows you to completely restore the original activity of the catalyst for oxidation of carbon monoxide.
As follows from the above, each of the signs stated together to a greater or lesser extent affect the achievement of objectives, and the entirety is sufficient to characterize the claimed technical solution.
The activation method of the catalyst for oxidation of carbon monoxide, including its heat treatment, characterized in that the activation lead by heating the catalyst layer thickness of 2-3 cm to 180-380°With the speed of temperature rise 10-20°/min at a constant tap of products of reactivation.
FIELD: catalyst preparation.
SUBSTANCE: invention relates to supported catalysts and provides a method for preparing catalyst-containing solid product comprising step, wherein ceramic carrier is applied onto metallic surface, and depositing catalytically active material onto ceramic carrier, which was preliminarily coated with supporting porous metallic material, ceramic carrier being applied onto and/or into supporting porous metallic material. Invention also describes device used in preparation of catalyst-containing solid product for applying supporting porous material onto inside or outside metallic surfaces of the hollow body.
EFFECT: increased stability of catalyst.
7 cl, 2 dwg
FIELD: production of carbon carrier for catalysts.
SUBSTANCE: proposed method includes heating of moving layer of granulated furnace black used as backing, delivery of gaseous or vaporous hydrocarbons into soot layer followed by their thermal decomposition on soot surface forming layer of pyrocarbon at forming of layer of pyrocarbon and activation of material compacted by pyrocarbon at temperature of 800-900°C and unloading of finished product. Granulated furnace black at specific surface of 10-30 m2/g and adsorption rate of 95-115 ml/100 g is used as backing for compacting with pyrocarbon. Then, product is subjected to activation for obtaining total volume of pores of 0.2-1.7 cm3/g. Black is compacted by pyrocarbon at two stages: at first stage, granulated black is compacted to bulk density of 0.5-0.7 g/cm3, after which material is cooled down and screened at separation of fraction of granules of 1.6-3.5 mm; at second stage, this fraction is subjected to repeated pyrolytic compacting to bulk density of granules of 0.9-1.1 g/cm3.
EFFECT: enhanced economical efficiency; increased productivity of process.
FIELD: organic synthesis catalysts.
SUBSTANCE: invention relates to methods of preparing catalysts based on sulfurized styrene/divinylbenzene copolymer and thermoplastic polymer material, which are used in processes for preparing alkyl tert-alkyl ethers, hydration of olefins, dehydration of alcohols, preparation of esters, and the like. Invention provides molded ionite catalyst consisted of sulfurized styrene/divinylbenzene copolymer in the form of mixture of powdered copolymers with macroporous and gel structure and, as thermoplastic material, propylene polymers and propylene/ethylene copolymers. Preparation of catalyst is accomplished by extrusion at temperature of heating extruder cylinder 140-200°C and temperature of forming head equal to temperature of the last heated zone of heating cylinder.
EFFECT: increased catalytic activity.
10 cl, 3 tbl, 15 ex
FIELD: alternative fuel production and catalysts.
SUBSTANCE: invention relates to (i) generation of synthesis gas useful in large-scale chemical processes via catalytic conversion of hydrocarbons in presence of oxygen-containing components and to (ii) catalysts used in this process. Catalyst represents composite including mixed oxide, simple oxide, transition element and/or precious element, carrier composed of alumina-based ceramic matrix, and a material consisting of coarse particles or aggregates of particles dispersed throughout the matrix. Catalyst has system of parallel and/or crossing channels. Catalyst preparation method and synthesis gas generation method utilizing indicated catalyst are as well described.
EFFECT: enabled preparation of cellular-structure catalyst with high specific surface area, which is effective at small contact times in reaction of selective catalytic oxidation of hydrocarbons.
6 cl, 2 tbl, 16 ex
FIELD: petrochemical process catalysts.
SUBSTANCE: catalyst constitutes cements formed during heat treatment and depicted by general formula MeO·nAl2O3, where Me is at least one group IIA element and n is number from 1.0 to 6.0, containing modifying component selected from at least one oxide of magnesium, strontium, copper, zinc, indium, chromium, manganese, and strengthening additive: boron and/or phosphorus oxide. The following proportions of components are used, wt %: MeO 10.0-40.0, modifying component 1.0-5.0, boron and/or phosphorus oxide 0.5-5.0, and alumina - the balance. Catalyst is prepared by dry mixing of one group IIA element compounds, aluminum compounds, and strengthening additive followed by mechanochemical treatment on vibromill, molding of catalyst paste, drying, and calcination at 600-1200°C. Modifying additive is incorporated into catalyst by impregnation and succeeding calcination. Method of pyrolysis of hydrocarbon feedstock producing C2-C4-olefins is also described.
EFFECT: increased yield of lower olefins.
3 cl, 2 tbl, 18 ex
FIELD: supported catalysts.
SUBSTANCE: invention claims a method for preparation of catalyst using precious or group VIII metal, which comprises treatment of carrier and impregnation thereof with salt of indicated metal performed at working pressure and temperature over a period of time equal to or longer than time corresponding most loss of catalyst metal. According to invention, treated carrier is first washed with steam condensate to entirely remove ions or particles of substances constituted reaction mixture, whereupon carrier is dried at 110-130oC to residual moisture no higher than 1%.
EFFECT: achieved additional chemical activation of catalyst, reduced loss of precious metal from surface of carrier, and considerably increased lifetime.
5 cl, 9 ex
FIELD: petroleum processing catalysts.
SUBSTANCE: invention provides reforming catalyst containing Pt and Re on oxide carrier, in particular Al2O3, wherein content of Na, Fe, and Ti oxides are limited to 5 (Na2O), 20 (Fe2O3), and 2000 ppm (TiO2) and Pt is present in catalyst in reduced metallic state and in the form of platinum chloride at Pt/PtCl2 molar ratio between 9:1 and 1:1. Contents of components, wt %: Pt 0.13-0.29, PtCl2 0.18-0.04, Re 0.26-0.56, and Al2O3 99.43-99.11. Preparation of catalyst comprises impregnation of alumina with common solution containing H2PtCl6, NH4ReO4, AcOH, and HCl followed by drying and calcination involving simultaneous reduction of 50-90% platinum within the temperature range 150-550оС, while temperature was raised from 160 to 280оС during 30-60 min, these calcination conditions resulting in creation of reductive atmosphere owing to fast decomposition of ammonium acetate formed during preparation of indicated common solution.
EFFECT: increased catalytic activity.
2 cl, 1 tbl, 3 ex
FIELD: hydrocarbon conversion catalysts.
SUBSTANCE: catalyst for generation of synthesis gas via catalytic conversion of hydrocarbons is a complex composite composed of ceramic matrix and, dispersed throughout the matrix, coarse particles of a material and their aggregates in amounts from 0.5 to 70% by weight. Catalyst comprises system of parallel and/or crossing channels. Dispersed material is selected from rare-earth and transition metal oxides, and mixtures thereof, metals and alloys thereof, period 4 metal carbides, and mixtures thereof, which differ from the matrix in what concerns both composition and structure. Preparation procedure comprises providing homogenous mass containing caking-able ceramic matrix material and material to be dispersed, appropriately shaping the mass, and heat treatment. Material to be dispersed are powders containing metallic aluminum. Homogenous mass is used for impregnation of fibrous and/or woven materials forming on caking system of parallel and/or perpendicularly crossing channels. Before heat treatment, shaped mass is preliminarily treated under hydrothermal conditions.
EFFECT: increased resistance of catalyst to thermal impacts with sufficiently high specific surface and activity retained.
4 cl, 1 tbl, 8 ex
FIELD: oxidation catalysts.
SUBSTANCE: invention relates to oxidation catalysts that can be, in particular, used for complete oxidation of volatile organic compounds into CO2 and H2O. Catalyst according to invention contains mixed copper, manganese, and lanthanum oxides, wherein metals can assume multiple oxidation states and whose chemical analysis expressed for metals in lowest oxidation states is the following: 35-40% CuO, 50-60% MnO, and 2-15% La2O3.
EFFECT: enhanced stable catalytic activity and resistance to caking.
11 cl, 2 tbl, 2 ex