Method of recovering catalyst for low-temperature conversion of carbon monoxide
(57) Abstract:The described method of recovery of the catalyst of low-temperature conversion of carbon monoxide related to the production process gases and which can be used to obtain nitric gas mixture. In the method instead of the separate inert gas and hydrogen through the catalyst bed is suggested to use the products of incomplete combustion of natural gas containing hydrogen and enriched with water vapor. The content of carbon monoxide in an inert gas in the process of recovery of the catalyst in the range of 0.1-10% regulate the consumption of natural gas supplied to the combustion. Removing the formed condensate is carried out in the cooling of exhaust gases. The method allows to simplify the process and control of technological operations. 2 C.p. f-crystals. 1. Object technology.The present invention relates to the production of process gases and can be used for recovery of catalysts for low-temperature conversion of carbon monoxide used, for example, upon receipt of nitric gas mixture for the glass industry, metallurgy, mashinostroyitelny conversion of carbon monoxide used in various technological processes, in particular, when receiving attachoptions a controlled atmosphere.The production of nitric gas mixture includes the following main processes: high-temperature incomplete combustion of natural gas, low-temperature steam reforming of carbon monoxide, cooling the products of combustion and separation of condensed moisture, pressure adsorption purification of combustion products from moisture and carbon dioxide.The gas mixture produced in the nitric plant with a capacity of gas ready from 100 to 500 m3per hour, each of which consists of the following blocks: block burning, the conversion block, and the cooling unit, the unit adsorption adsorption.To improve air quality by reducing the content of hydrocarbons with steam conversion of carbon monoxide used low-temperature zinc-chromium-copper catalyst, the operating temperature which is in the range of 160-220oC, to ensure maximum activity which requires careful restoration.A known method of recovering low-temperature catalyst for conversion of carbon monoxide /reference guide katalizatorami way exothermic recovery of copper-containing catalysts is carried out according to the following scheme:
- purge the catalyst invert gas to remove air;
- heat the catalyst in a stream of inert gas to the 120oC at 50oC per hour;
- flow of inert gas through the catalyst with a volume rate of about 600 hours-1gradually adding hydrogen to 0.5 mol%;
- increase the temperature in the layer 180oC at a rate of about 30oC per hour;
- when you set the recovery mode, increase the temperature to 200oC for one hour;
within three hours increase the hydrogen concentration up to 1.5%, by the end of the recovery for a given concentration of hydrogen increase the temperature to 225oC;
- remove the condensate /water/ in the recovery process;
special attention is paid to the fixing of an amount of hydrogen consumed in the recovery /1 m3catalyst/. In addition, conduct additional monitoring of the process of recovery of the catalyst by determining the quantity of water given in the process restore to 1 m3catalyst;
- raise the hydrogen concentration up to 10% when the inlet temperature of 225oC.The main disadvantages of the method are the following: the complexity osushestvleniya, various sequence diagram their feed, constant speed control of the temperature increase of the amount spent on the recovery of hydrogen and the amount of water formed during the recovery/.Also noteworthy is the high temperature in the recovery process.3. The essence of the invention.In the proposed method of recovery of the catalyst of low-temperature conversion of carbon monoxide, the recovery process carried out at constant pressure of the inert gas as the inert gas used products of incomplete combustion of natural gas containing hydrogen and obogashenie water vapor, and removing condensate water is carried out after the recovery process.Recovery of the catalyst is carried out in the Converter by feeding through a layer of catalyst products of incomplete combustion of natural gas containing hydrogen, for example, after the burning of natural gas in the process of obtaining nitric atmospheric nitric installations. The gas mixture enriched with water vapor, is fed at a constant pressure of 30 to 60 kPa and a temperature of 160-180oC. the Content of carbon monoxide rises gradually in the process of reconstruction is Stanovlenie catalyst the hydrogen content at the outlet of the Converter must be set approximately equal to the total content of carbon monoxide and hydrogen at the input of the Converter. The content of carbon monoxide in an inert gas in the recovery process within 0.1-10% regulate the consumption of natural gas supplied to the combustion. The condensate generated during the recovery of the catalyst is removed separately in the cooling unit.4. Information confirming the possibility of carrying out the invention.Products of incomplete combustion of natural gas produced in the process of obtaining nitric controlled atmosphere, with a constant pressure of 40-50 kPa, enriched with water vapor, and with a constant temperature of 160-180oC are fed into the Converter to recover the zinc-chromium-copper catalyst for low-temperature conversion of carbon monoxide. The content in the products of incomplete combustion of natural gas of carbon monoxide is from 0.1% with a gradual increase up to 10% with full recovery of the catalyst, is regulated by the consumption of natural gas is fed to the combustion in the combustion chamber. During recovery of the Converter, the temperature in the zones of the Converter must not exceed 240oC. When the temperature in the zones of the Converter above 240oC necessary to reduce the content of carbon monoxide at the input of the Converter.In blithedale is equal to the total content of carbon monoxide and hydrogen at the input of the Converter. To determine this ratio, you need to periodically analyses on chromotography combustion products after the Converter.The condensate formed during the restore, remove the cooling unit flue gas. 1. Method of recovering catalyst for low-temperature conversion of carbon monoxide at a temperature of 120 to 225°C by separate feed through the catalyst bed of inert gas and hydrogen, and selection of water generated in the recovery process, characterized in that as the inert gas used products of incomplete combustion of natural gas containing hydrogen and enriched with water vapor, recovery of the catalyst is carried out at constant gas pressure of 30 to 60 kPa, and the content of carbon monoxide in an inert gas in the recovery process within 0.1 - 10 % regulate the consumption of natural gas supplied to the combustion.2. The method according to p. 1, characterized in that the condensate drain is carried out in the cooling unit flue gas.3. The method according to p. 1, characterized in that as the inert gas used products of incomplete combustion of natural gas produced in the process of obtaining nitric controlled atmosphere.
There is a method of regeneration of vanadium catalyst for oxidation processes (AVT
FIELD: structural chemistry and novel catalysts.
SUBSTANCE: invention provides composition including solid phase of aluminum trihydroxide, which has measurable bands in x-ray pattern between 2Θ=18.15° and 2Θ=18.50°, between 2Θ=36.1° and 2Θ=36.85°, between 2Θ=39.45° and 2Θ=40.30°, and between 2Θ=51.48° and 2Θ=52.59°, and has no measurable bands between 2Θ=20.15° and 2Θ=20.65°. Process of preparing catalyst precursor composition comprises moistening starting material containing silicon dioxide-aluminum oxide and amorphous aluminum oxide by bringing it into contact with chelating agent in liquid carrier and a metal compound; ageing moistened starting material; drying aged starting material; and calcining dried material. Catalyst includes carrier prepared from catalyst composition or catalyst precursor and catalytically active amount of one or several metals, metal compounds, or combinations thereof. Catalyst preparation process comprises preparing catalyst carrier from starting material containing silicon dioxide-aluminum oxide and amorphous aluminum oxide by bringing it into contact with chelating agent and catalytically active amount of one or several metals, metal compounds, or combinations thereof in liquid carrier, ageing starting material; drying and calcinations. Method of regenerating used material involves additional stage of removing material deposited on catalyst during preceding use, while other stages are carried out the same way as in catalyst preparation process. Catalyst is suitable for treating hydrocarbon feedstock.
EFFECT: improved activity and regeneration of catalyst.
41 cl, 3 dwg, 8 tbl, 10 ex
FIELD: chemical industry; environmental protection technologies and methods of utilization of the waste mercury-containing catalyzer.
SUBSTANCE: the invention is pertaining to the field of environmental protection technologies, in particular, to the processes of utilization of the waste mercury-containing catalyzer for the process of hydrochlorination of the ethine. The invention presents the method of utilization of the mercury-containing catalyzer by its heating in the medium of the reducing gas, in the capacity of which use the residual gas of the high-temperature homogeneous pyrolysis of hydrocarbons. The heating is conducted at the temperature of 400-700°C within 4-7 hours. The technical result of the invention is the complete extraction (99.99 %) of mercury from the waste catalyzer, that transforms the mercury into the non-toxic substance.
EFFECT: the invention ensures the complete extraction of mercury from the waste catalyzer, that transforms the mercury into the non-toxic substance.
5 tbl, 6 ex, 1 dwg
SUBSTANCE: invention relates to the removal of the metallic catalyst from stock solution, obtained during the synthesis of carboxylic acids, normally terephthalic acid. Method of removing the metallic catalyst from the stream of stock solution containing carboxyl acid includes the following stages: (a) graduating the stock solution, which contains the carboxyl acid, metallic catalyst, impurities, water and solvent, in the zone of the first evaporator obtaining a stream of water vapour and a stream of concentrated stock solution; (b) evaporating of the specified stream of concentrated stock solution to the zone of the second evaporator forming a stream rich in the solvent and a stream of super-concentrated stock solution; (c) removing organic impurities from super-concentrated stock solution with the help of water-solvent solution in the zone of the separating phase of solid substance/liquid forming a stream of water and a second stream of water; (d) mixing in the zone of mixing water and not necessarily the extraction solvent with the specified water stream and the specified second water stream forming and aqueous solution; (e) adding the extraction solvent to the specified water solution in the extraction zone forming a stream of extract and a stream of raffinate containing the specified metallic catalyst; and (f) separating the specified stream of extract in the separating zone forming a stream of organic impurities with a high boiling point and a stream of the removed extraction solvent. In a different version of the realisation of the method of removing the metallic catalyst from the stream of stock solution containing the carboxylic acid includes the following stages: (a) evaporating of the stock solution containing the carboxylic acid, metallic catalyst, impurities, water and solvent, in the zone of the first evaporator obtaining a stream of water and a stream of concentrated stock solution; (b) evaporating the specified stream of concentrated stock solution in the second evaporating zone obtaining a stream rich in the solvent and stream of super-concentrated stock solution, where about 85 to about 99% mass, of the solvent and water is removed from the specified stock solution at the stage (a) and stage (b) in combination; (c) removing of organic impurities from the specified super-concentrated stock solution with help of the water-solvent solution in the zone of the separating phase of solid substance/liquid forming a stream of water and a second stream of water; where the specified water-solvent solution is introduced to the specified zone of the separating phase of solid substance/liquid at a temperature interval from about 20°C to 70°C; (d) mixing in the zone for mixing water and not necessarily the extraction solvent with the specified stream of water and the specified second water stream forming a water mixture; (e) introducing the extraction solvent to the specified water solution to the extraction zone forming a stream of extract and a stream of raffinate; and (f) separating of the specified flow of extract in the zone of separation forming a flow of organic impurities with a high boiling point and a flow of the extraction solvent removed.
EFFECT: increase in the efficiency of the method of removing impurities and working capacity of the method in comparison to the existing methods.
17 cl, 1 tbl, 1 dwg
SUBSTANCE: present invention pertains to extraction of a metallic catalyst from a mother solution, obtained during synthesis of carbonic acid, usually terephthalic acid. In the first version, the method of separating metallic catalyst from a stream of mother solution involves the following stages: (a) evaporation of the mother solution, containing carbonic acid, the metallic catalyst, impurities, water and a solvent, in the zone of the first evaporator, obtaining a vapour, containing water and solvent, and concentrated mother solution; (b) evaporation of the concentrated mother solution in the zone of the second evaporator, where evaporation in the zone of the second evaporator is carried out at 150-220°C temperature, forming a stream rich in solvent and a stream of super-concentrated mother solution in molten dispersion state, where a total of 95-99 wt % of solvent and water is removed from the mother solution during evaporation stages (a) and (b); (c) mixing the water-solvent solution in the mixing zone, with super-concentrated mother solution, forming an aqueous mixture; (d) separation of organic impurities in the aqueous mixture in the separation zone of solid substance/liquid phase, forming a pure aqueous mixture; (e) addition of extraction solvent to the aqueous mixture or pure aqueous mixture in the extraction zone, forming an extract or rafinate, containing the metallic catalyst; and (f) separation of the extract and the solvent rich stream in the separation zone, forming a stream of organic impurities with high boiling point and a stream of extraction solvent. The invention has three versions.
EFFECT: extraction of expensive metallic catalyst in active form, suitable for repeated use, and acetic acid, contained in the mother solution with removal of most impurities present in the extracted stream.
20 cl, 1 tbl, 1 dwg
SUBSTANCE: product of olefins epoxidation by organic peroxides are fractionated, the molybdenum-containing heavy fraction is washed from the oxidation by-products with caustic soda solution. The ligand is added to the obtained worked out alkali solution in order to bind the dissolved molybdenum to metal-organic complex with following mixture treatment with extragent at temperature equal to (1-1.18) Tcr and pressure equal to (1.36-3.4) pressure Pcr whereat Tcr is critical temperature and Pcr is critical pressure of the extragent. The molybdenum-containing compounds are precipitated from extract.
EFFECT: increased degree of molybdenum extraction (45,38% - 98,36%) from the worked out alkali solution independently of its composition.
1 dwg, 2 tbl, 6 ex
FIELD: process engineering.
SUBSTANCE: invention relates to method of reactivating thermally aged catalytic neutralisers-accumulators of nitrogen oxides containing compounds accumulating nitrogen oxides on carrier material containing cerium oxide. Invention covers the method of reactivating thermally aged catalytic neutraliser-accumulator of nitrogen oxide that comprises main compounds of strontium or barium, or both, on carrier material containing cerium oxide and contains compounds of strontium and/or barium formed due to thermal ageing with carrier material. Note here that compounds of strontium and/or barium with carrier material are decomposed by treating them with gas mix at 300°C to 500°C, said gas mix containing nitrogen oxide in amount of 0.05 to 5 % by volume, water steam in amount of 5 to 15 % by volume and carbon dioxide in amount of 0 to 20 % by volume. Proposed method (version) comprises dismantling, during scheduled servicing, of catalytic neutraliser-accumulator of nitrogen oxides that makes an integral part of exhaust system incorporated with vehicle driven by engine running on depleted fuel and treatment for 0.1 to 5 h by gas mix containing nitrogen oxides in amount of 35 % by volume, oxygen in amount of 5 to 50% by volume, water steam in amount of 5 to 30 % by volume, carbon dioxide in amount of 0 to 20 % by volume, and, not obligatorily, nitrogen in amount of approximating to 100 % by volume.
EFFECT: partial reactivation of catalytic neutraliser-accumulator of nitrogen oxides after its thermal damage.
8 cl, 3 ex, 5 dwg
FIELD: oil and gas industry.
SUBSTANCE: invention refers to oil refining, and namely to reactivation methods of catalysts for dehydrogenation of higher paraffins (C10-C13) at reduction of efficiency during the operation. There described is reactivation method of catalyst for dehydrogenation of paraffin hydrocarbons C10-C13, which consists of platinum, metals-promoters of the group indium and/or stannum, and/or cerium, and/or molybdenum, and light metals-modifiers, e.g. magnesium, calcium, potassium, sodium, which are applied to porous heat resistant carrier - active aluminium oxide or aluminium silicate, in which the above reactivation of catalyst is performed in presence of carbon dioxide in two stages, first in nitrogen-air-CO2 with low constant CO2 concentration about 0.003 vol. % or with subsequently increasing concentration - 0.0001 to 0.003 vol. %, and then in steam-air mixture with additive of chlorine hydride and increased CO2 concentration but not exceeding 0.03 vol. %.
EFFECT: increasing selectivity and stability of catalyst operation.