Catalyst for hydrogenation of unsaturated compounds and a method for its preparation
(57) Abstract:The inventive product-catalyst (CT) - copper uniformly distributed over the surface of the amorphous klostergasse media with a particle size of copper from 3010-10to 30010-10m with an average particle size 5010-10m and surface area 18,38-18,61 m2/g determined by decomposition at 80°C of nitric oxide. When this atomic ratio of copper and chromium 1,2 - a 2.5 : 1.CT may optionally contain 10 wt.% barium oxide. CT get recovery mednografitovaya composition by adding hydrogen in a stream of nitrogen at ambient temperature, with the consequent increase of temperature recovery and hydrogen concentration with the control of the gas composition at the outlet so that the compositions of the gases at the inlet and outlet were identical. Vosstanovlenie lead to complete replacement of nitrogen to hydrogen with keeping the temperature recovery in the range of 140 to 180°C. the total pressure of the gas can be 4,45 bar at a partial pressure of hydrogen 0,009 - 0,023 bar. Temperature recovery increase with adjustable rate of 10°C/h from ambient temperature to 120°C at a hydrogen concentration in the gas flow of 0.2 - 0.5 vol.%. The temperature rise 120 - 170°C are carried out by the who. C. and 6 C.p. f-crystals, 1 Il., 7 table. The invention relates to heterogeneous catalysis and concerns of the catalyst for hydrogenation of unsaturated compounds containing recovered mednografitovaya composition of the copper particles, uniformly distributed over the surface of amorphous chromium media. Another object of the invention is a method for preparing a catalyst for hydrogenation of unsaturated compounds by processing mednografitovaya composition a stream of nitrogen and then adding in a stream of nitrogen with hydrogen at elevated temperature and with increasing hydrogen concentration up to full replacement of nitrogen with hydrogen and the temperature of the recovery in regulated recovery options.In patent documents EP-A-0143634 and WO-A-86/03189 Described two - and multistage process of hydrogenation in the vapour phase of diallylmalonate [1,5], for example, diethylmaleate, butane-1,4-diol. Technique pre-recovery involves a preliminary heating odnokratnogo catalyst to 175aboutC in an atmosphere of nitrogen under the pressure of 42 bar, followed by passing over the catalyst gas mixture of hydrogen and nitrogen containing 2% of hydrogen for 8 h, zafa for 12 h of pure hydrogen. In the application described the process  preliminary recovery of the catalyst, which for several days over the catalyst is passed a mixture of hydrogen and nitrogen (containing 1-15% hydrogen) having a temperature in the range of about 120 to 180aboutC.Recommended  the preliminary restoration magnochromite catalysts in hydrogen atmosphere under a pressure in the range from 0.01 to 10 ATM at 100-450aboutC.The described process  obtain ethylene glycol, whereby the reaction of hydrogen with dialkylanilines in the vapor phase is over mediocrity catalyst. This publication describes a method of recovering catalyst, which imedica on sale mediocrity catalyst Calsicat Code" NE-103TR after grinding is mixed with approximately an equal volume of gamma-aluminium oxide and then heated to 140aboutC at heating rate of approximately 28-58aboutWith 1 h in nitrogen atmosphere, and then for 3h heated in a stream of hydrogen and nitrogen (hydrogen content of 0.5 mol. %), followed by a gradual increase in the content of hydrogen in the flow to 100% with increasing temperature up to 180-240aboutC.Despite the fact that domestic implementation processes in the liquid phase, the catalyst often is restored to the place in the presence of an ether carboxylic acid or other liquid hydrogenstorage material or its solution in an inert solvent.Examples of implementation of such processes are described in the patent GB-A-1344557.The described method  preliminary recovery odnokratnogo catalyst in which the catalyst is heated to a temperature of 200-260aboutC in an atmosphere of hydrogen under pressure in the range of 100-300 kg/cm2. In the patent document GB-A-1459335 method activation odnokratnogo catalyst that set - out heating of the catalyst in a stream of hydrogen over a period of time from 1 to 10 hours at a temperature in the range from 200 to 300aboutC.There is a need to develop improved method of pre-recovery magnochromite catalysts, providing a much more active catalyst for hydrogenation reactions.Thus, the object of the invention is a catalyst for hydrogenation of unsaturated compounds containing recovered mednografitovaya composition of the copper particles, uniformly distributed over the surface of amorphous chromium carrier, characterized in that, to increase activity of the copper particles have a size from h-10to 30010-10m with an average particle size 5010-10m and a specific surface area, on which retenu preferably contains copper and chromium atomic ratio of from 1.2:1 to 2.5:1.The catalyst according to the invention further preferably additionally contains 10 wt. % barium oxide.Another object of the invention is a method for preparing a catalyst for hydrogenation of unsaturated compounds recovery mednografitovaya compositions by treating the composition with the stream of nitrogen, followed by pressure in a stream of nitrogen with hydrogen at elevated temperature and with increasing hydrogen concentration up to full replacement of nitrogen with hydrogen and the temperature of the recovery in regulated settings restore, characterized in that, in order to obtain the catalyst of increased activity, the addition of hydrogen to begin at ambient temperature, the temperature of the restoration carried out by adjusting the composition of the gases at the inlet and outlet so that the compositions of the gases at the inlet and outlet were practically identical to each other, and the catalyst is kept in a reducing atmosphere until a temperature recovery, appropriate 140-180aboutC.To restore according to the invention can be achieved by keeping the catalyst in a reducing atmosphere at a total gas pressure of 4.45 bar and a partial pressure of Vodogray environment 120aboutWith variable speed 10aboutC/h, when the hydrogen concentration in the gas stream component of 0.2-0.5% vol.In the method according to the invention preferably the temperature increase is carried out in the range of 120-170aboutWith linearly with speed from 5 to 10aboutS/hPreferably the temperature increase in the range of 120-170aboutTo carry out when the gas flow with a bulk velocity, designed for temperatures 0aboutC and a pressure of 1 bar is equal to 3000-6000 h-1.As starting material for the preparation of magnochromite catalysts, it is preferable to use a material in which the atomic ratio of copper to chromium (Cu : Cr) is in the range of about 0.2 : 1 to 4 : 1, for example, of 2.5 : 1. Often the atomic ratio of Cu : Cr is in the range of about 0.6 : 1 to 2.0 : 1, and in General in the range approximately from 0.75 : 1 to 1.5 : 1. In some preferred the raw materials and the atomic ratio of Cu : Cr is in the range of about 1.2 : 1 to 1.4 : 1, for example, is 1.3 : 1. Additional starting materials for the preparation of the catalysts may contain any conventional carriers, binders and/or promoters. Thus, the original Materov, for example, gamma-aluminum oxide, barium oxide and manganese oxide. Mediocrity source material may be deposited on an inert carrier, for example, alpha-alumina, a mixture of silicon oxide and aluminum oxide, thorium oxide, silicon carbide, titanium oxide, zirconium oxide and carbon monoxide. The content of the media in the source material for the catalyst may be in the range of about 1 to 15 wt. %.It is desirable that the source material for the catalyst had a specific surface area measured by a known method BET method of brunauer, Emmett and teller) at least 2 m2/g, preferably about 40 m2/year In the General case, the source material must be in the form of powder with particle sizes less than 100 microns. From this powder by known methods can produce catalytic elements of any desired configuration, for example, in the form of cylindrical pellets, rings and other forms using conventional binders. Such catalysts can be used in processes with a fixed catalyst bed.The source material for catalysts may serve chromite copper, both in pure form and promoted with barium chromite, copper, or chromium is the AI of the present invention, the operation of keeping the original odnokratnogo material consists in keeping it in an atmosphere of reducing gas at a temperature in the range between ambient temperature (approximately 65-25aboutSince, in the General case, 20aboutC) and the temperature of the provisional restoration, which in General is approximately 140aboutC. Maintaining the source material may begin at temperatures below ambient temperature, for example at a temperature of 0aboutC and below. During the operation, keeping the reducing gas atmosphere may contain hydrogen or any other reduction gas, for example, carbon monoxide or a mixture of carbon monoxide and hydrogen. Preferably during the entire operation-keeping, when the raw material of the catalyst is heated from ambient temperature to the temperature of the provisional restoration, to maintain a reducing gas atmosphere, however, to start the heating in the atmosphere of inert gas and the reducing gas to enter the zone at an elevated temperature, for example at a temperature of approximately 40-50aboutC. an Important condition for the implementation of operations-keeping, however, is that the more the temperature of the heating material is close to the temperature of the provisional restoration, the greater the importance of the constancy of the contact of the source material from vosstanovlenieplastika it is best to heat in controlled conditions from ambient temperature (e.g., from a temperature of about 20about(C) in a stream of reducing gas. As the reducing gas, it is preferable to use a mixture consisting of a small amount of hydrogen and the rest one or more inert gases, such as nitrogen, argon, neon, methane, ethane, propane, butane or a mixture of two or more of these gases. The best results are achieved in cases where the reducing gas is a mixture of a small amount of hydrogen and the rest is nitrogen, preferably not containing oxygen.Operation keeping the source material for catalysts in accordance with the principles of the present invention can be carried out at normal or reduced pressure, but it is preferable to produce the curing at an elevated pressure in the range of about 1 to 20 bar, preferably in the range of about 2 to 10 bar.The partial pressure of hydrogen or other reducing gas during the operation-keeping should be no higher than approximately 0.1 bar and must be in the range of about 0.005 to 0.05 bar.In accordance with the present invention, the source material for the catalyst, it is best to heat from temperable amount of hydrogen. The preferred heating source material from ambient temperature to a temperature of approximately 120aboutWith should preferably be variable speed. In the General case of the operation pre-heating may last from about 30 minutes to 3 hours or more, for example, about 90 minutes During the operation, keeping the temperature can be increased with a linear speed or small jumps, for example, irregular, approximately 5-10aboutC, followed by maintaining the temperature for a certain period of time. Heating the source material for the catalyst from the 120aboutWith approximately 170aboutWith can be done with any speed at which supported the recovery mode and the composition of the gas at the inlet and outlet zones of the preliminary recovery remains identical. Preferably, the temperature of the source material for the catalyst, during heating of the material temperature 120aboutWith approximately 170aboutWith increased approximately linearly. At step heating of the source material it is preferable that each leap temperature of approximately 10aboutWith and at the same time it is necessary , the increase of temperature, during this jump, and after the jump. In the General case, the rate of increase of temperature in the range of 120aboutWith approximately 170aboutC should be in the range of approximately from 1aboutS/h to 15aboutC/h, for example, it may be approximately 10aboutC.During the operation of heating a starting material for the catalyst temperature to approximately 120aboutWith up to 170aboutWith time the flow of gas, measured at 0aboutC and a pressure of 1 bar in the General case can be in the range of from about 400 h-1up to 6000 h-1and more, for example, it may be 3000 h-1.The composition of the reducing atmosphere depends on the pressure in the zone prior vosstanovleniya. So, at higher total pressure maximum allowable concentration of hydrogen in the reducing atmosphere should be lower. On the contrary at a lower total pressure reducing atmosphere the concentration of hydrogen should be higher. In a typical case, the concentration of hydrogen at the optimum operating conditions can be in the range of about 0.1 to 1.0 vol. % for example, it may be 0.5. %.After achievement of ivalsa, however, at this stage, the activation of the catalyst composition of the gas at the inlet and outlet zones of the provisional restoration should be strictly controlled so that during the entire period of operation, the gas composition was not changed.It is very important that the composition of the reducing atmosphere at the time when the temperature of the source material for the catalyst reaches the temperature of the provisional restoration, there was an excess of hydrogen or other reducing gas, as otherwise there is a danger of destruction of the catalyst due to thermal decomposition due to ekzotermicheskie reaction of the provisional restoration.After the operation is completed prior recovery of the catalyst must be kept in hydrogen or inert gas atmosphere, as it eliminates the possibility of re-oxidation pre recovered catalyst.Pre recovered catalyst is relatively easily oxidized, which is probably due to reverse oxidation of metallic copper. Found that with careful reverse pre-oxidation of the recovered catalyst, prepared the receipt of the catalyst with increased activity, which was achieved during the initial recovery, and the dimensions of the metal particles of copper are as small and restores the initial specific surface area of particles of copper, as measured by the decomposition of nitrogen oxide (N2O. Thus, the method according to the invention provides a reverse oxidation pre recovered catalyst without sintering particles of metallic copper and their agglomeration.The method according to the invention leads to the formation of much larger open surface of copper. Thus, when the pre-recovery according to the invention in their preferred preliminary chromite copper achieves an open surface restored mednarodno catalyst of about 18.5 m2/,Increased open copper surface in the restored mednarodna catalyst, in turn, leads to increased catalytic activity is restored mednarodno catalyst hydrogenation.Another advantage of the invention is that if the pre-catalyst is a catalyst, previously restored according to the invention, e is about 18,5 m2/g), but in the fact that the recovered catalyst, if appropriate safety precautions, may be subjected to air exposure for obtaining a stabilized form of the catalyst, which can then be restored even known methods for the preliminary recovery, such as the generally recommended method preliminary reduction to obtain the recovered catalyst, which will have the same large open copper surface (usually about 18.5 m2/g of catalyst), which has restored mediocrity the catalyst obtained according to the invention. In other words, after the preliminary recovery of the catalyst to obtain a large surface active particles of copper subsequent re-oxidation and subsequent re-instatement will not significantly reduce the activity of the catalyst.The practical advantage of this unexpected property of the invention is that the operator can be purchased from the manufacturer of catalysts stabilized pre-kata - lyst, which may be subjected to air exposure and to boot into the installation in the usual way, and which saturometer hydrogenation catalyst with a higher catalytic activity in comparison with the known pre-restored magnochromite catalysts for hydrogenation.In the recovered catalyst is measured specific surface area of an open metallic copper. The measurement is completely different compared to the dimension of the inner surface of the catalyst, which is well-known BET method, in which all measured specific surface of the pre-catalyst. Thus, the catalyst precursor may have a surface, measured by BET method, up to 40 m2. If the catalyst precursor be recovered by conventional means, the open surface of metallic copper (determined by the decomposition of N2O at 20aboutC) is only about 4.5 m2/, whereas the recovery according to the invention this surface may reach 18,5 m2/,When carrying out chemical analysis of the recovered mednarodno catalyst according to the invention the difference between the content of copper and chromium content may be low or completely absent in comparison with the results of the analysis of the same mednarodno compounds recovered according to known methods prior recovery.Restored mediocrity katalizatoriai re-oxidation.As mentioned above, the catalytic activity is restored mednarodno hydrogenation catalyst, as expected, depends on the open surface area of copper in the recovered catalyst. It is assumed that the more open area of the surface of the copper metal, the higher the catalytic activity.This mednarodna composition has a low content of copper per 1 g of the composition. Total open surface area of copper in the restored mednarodna the hydrogenation catalyst will be determined according to how the copper is distributed in the recovered composition. This surface area will depend on three factors: (a) size, (b) form and (C) number of particles of metallic copper in the restored mednarodna catalyst. The size of the copper particles and the number of copper particles are linked; if the particles are large, their will be less, whereas if the particles are small, they will be more per 1 g of the recovered catalyst.The shape of the copper particles is of great importance for the open surface area. Copper has a cubic crystal structure. Therefore, it easily forms a cubic particles. However, the eat thinner plate, the greater the surface area for a given mass of copper. Therefore, theoretically it is possible to show that the catalyst of very small thin plates of copper on amorphous chromium base is likely to have a greater catalytic activity than the restored mediocrity catalyst nominally the same composition, in which the recovered metal copper is in the form of particles of cubic form.In the restored mednarodna the catalyst contains particles of metallic copper dispersed on amorphous chromium base. Copper particles are oriented randomly. Only those particles that are oriented exactly to the x-ray diffraction, cause diffraction. Moreover, the strength of a picture of the x-ray diffraction depends on the size of participating in this crystal. If the crystals are too small, the diffraction is so weak that formed a very poor range of diffraction.When relatively large particles in the spectrum of diffraction is formed persistent peak. When the particle size of copper decreases, this peak becomes less peaked and becomes broader. If the particles are too small, they do not form a plane, to which Irakli x-rays can be used as a rough method of determining particle size. Of course not all particles of metallic copper in a particular sample of recovered copper chromite will be the same size, so the best thing to do is to determine the average particle size according to the width of the peak of the spectrum of x-ray diffraction. However, this is at best a rough method of determining particle size.A more accurate determination of the particle size of the copper and the open area of the copper surface can be achieved by electron microscopy and by measuring the decomposition of N2O. Application of electron microscopy to the recovered copper chromite indicates that the majority of the particles had sizes in the range h-10m/30 / - h-10m/50 /. The decomposition of N2O indicates that this is the largest surface area of metallic copper in the material of the applicants (18,58 m2/g), which only can be achieved, given a constant amount of copper present in the material, due to the many small particles (probably in the form of plates).Although difficult to prove exactly what is the difference between the proposed restored mediocrity catalyst for the hydrogenation of applicants and the recovered catalysts known - tion previously, us thin flat plates, and not in the form of cubic particles. Therefore, even when compared with cubic particles nominally the same size copper particles present in the recovered material, form a much larger surface area open copper than previously known materials.Hydrogenaudio catalysts embodying the principles of the present invention, suitable for use in various processes of hydrogenation of unsaturated organic compounds to obtain at least one product of hydrogenation. Such unsaturated organic compounds include ethers, carboxylic acids, aldehydes, ketones, heterocyclic compounds, nitro compounds, and compounds with olefinic unsaturated bonds. Another application of hydrogenosome catalysts embodying the principles of the present invention is their use in the processes of dehydrogenization primary alcohols to aldehydes. Such reactions under appropriate conditions can be carried out in the liquid and steam phases. The reaction in the vapor phase can be performed under normal and more often at high pressure, which is generally in the range from 1 to 250 bar, at elevated temperatures, which may be hydrogenosomal using catalysts, embodying the principles of the present invention include esters of monocarboxylic, and dibasic polycarboxylic acids with saturated alcohols (for example, alkanols), diatomic alcohols or glycols or polyhydric alcohols (for example, glycerole).The esters that has commercial value for the production of alcohols by hydrogenation are complex alkylether alkylcarboxylic acids having the General formula
R. CO.Or SIG', where R and R' are independent of one another alkyl radicals containing 1-18 carbon atoms, including methyl acetate and ethyl acetate to ethanol, n - propylphosphonate - to obtain n - propanol, n - butylboronic - to obtain n - butanol, 2-ethylhexyl 2-ethylhexanoate - to obtain 2-ethylhexanol, meilleures - for dodecanol, metilsulfate and methylsiliconate for receiving hexadecanol, methyltert, methylmaleic and meilleret - for octadecanol. Other important technical esters for hydrogenation include glycerides of fatty acids with long chains to obtain the corresponding alkanols with long chains, for example, glyceraldehyde, and alkylether glycolic acid, for example, methylglycol and ethylglycol - for p is tokenization, include dialkylamines, for example, dimethyloxalate and diethyloxalate to obtain ethylene glycol, and diallylmalonate, fumarate and succinate, for example dimethyl, diethyl and di-n-butylmalonate, fumarate and succinate - for butane-1,4-diol, gamma-butyrolactone and tetrahydrofuran. In the General case, the reaction in the vapor phase is produced at a pressure in the range of about 5-50 bar, at temperatures in the range from approximately 150aboutWith up to 240aboutAnd when the molar ratio of hydrogen to air in the range from about 100 : 1 to 500 : 1. Reactions in the liquid phase is carried out at higher values of pressure and temperature, which in General comprise at least 70 bar and 240aboutS, respectively. For example, the pressure may be in the range of about 200-280 bar and the temperature is in the range of about 280-330aboutC.The aldehydes which can be hydrogenosomal in the corresponding primary alcohols include benzaldehyde, furfural and n - Butyraldehyde. To ketones, which can be hydrogenosomal in the secondary alcohols using catalysts embodying the principles of the present invention include acetone, methyl ethyl ketone, pinacolone, benzophenon and acute heterocyclic compounds, include: pyridine, and quinoline, of which the hydrogenation get piperidine and tetrahydroquinolin, respectively. Hydrogenation of nitrobenzene to aniline is an example of the hydrogenation reaction of nitro compounds. An example of the hydrogenation reaction of the compounds with unsaturated olarinoye connections with the use of catalysts embodying the principles of the present invention is the hydrogenation of cyclohexene to cyclohexane. In General, the hydrogenation reaction is carried out at a pressure in the range of about 5-150 bar and temperatures in the range of about 50-150aboutC. the Process of hydrogenation can be carried out both in liquid and in the vapour phase.P R I m e R 1. For the implementation described in this example, the process was used by the device (see drawing). In the apparatus was loaded with 50 ml granulated odnokratnogo source material for catalyst (mediocrity catalyst PG 85/1 firm "Davy Me Kee, London, 250 Euston Road, NWL 2G, UK). The source material is in the form of granules with sizes of approximately 2x2 mmRated connection of copper in magnochromite catalyst PG 85/1 was 42 wt. % and chromium of 26.5 wt. %, which corresponds to the atomic is alala 40 m2/,The heating apparatus was carried out using a fluidized sand bath (not shown). The gas is conducted through a reduction gear and a flow regulator (not shown). The gas produced by the tube 1 into the lower end of the evaporator 2, filled with steel balls 3. When the operation is completed prior recovery of the catalyst, which is described in detail below, the evaporator 2 through the pipe 4 was introduced a certain amount of liquid ether. The resultant vapor mixture of air and gas through the coil 5 of the preliminary heating was supplied into the reactor 6. The lower part of the reactor 6 is filled glass ball, which relies on the catalyst layer 7. The upper end of the reactor 6 outlet tube 8 is connected to a condenser (not shown), which, in turn, is connected to a throttling valve (not shown). The gas flow at the outlet of the condenser was measured using a wet gas meter (not shown). The temperature of the output end of the catalyst layer 7 was measured using a thermocouple 9.For analysis of the condensate was used for gas chromatographic column consisting of a stainless steel tube length 1,82 m and internal diameter 3,18 mm Tube chromatograph the media helium was 30 ml/min The chromatograph was equipped with a flare ionization detector. The experimental setup was equipped with a tape recorder with an integrator. For calibration setup was used a mixture of diethylmaleate, diethylamine, gamma-butyrolactone, Bhutan N1,4-diol, tetrahydrofuran, ethanol and water of known composition. Identification of peaks in the chromatogram was carried out by comparing the observed retention times with the retention times of authentic samples of the material and using massspectrometry.A similar method is gas chromatography was used for analysis of the gas at the outlet of the experimental setup.The preliminary recovery of the catalyst was carried out as follows:
After loading into the reactor 6 50 ml granulated the original catalyst PG 85/1 all the installation was subjected to purging with nitrogen under pressure of 4.45 bar.When maintaining a constant pressure and flow rate of gas in nitrogen was added 0.5 to about. % hydrogen. For 1.5 h, the reactor temperature was increased from room temperature up to 120aboutC.When the temperature of the sand bath has reached 100aboutWith, was the analysis of the gas at the outlet of the installation in order to verify t is the period of one hour the temperature was increased from 120 to 130aboutWith, and every 15 min check was made of the concentration of hydrogen in the gas at the inlet and the outlet of the installation, which confirmed the constancy of the composition passing through the reactor gas.Next, the temperature was increased from 130 to 140aboutSince, then from 140 to 150aboutAnd then from 150 to 160aboutC. Each temperature increase produced within one hour. Each temperature increase of 10aboutWith began only after the establishment of the fact that the hydrogen concentration in the gas at the inlet and the outlet of the installation is the same.After the temperature reached 160aboutWith the temperature of the catalyst was maintained at this level until such time as the hydrogen concentration in the gas at the outlet of the installation was not equal to hydrogen concentration in the gas at the entrance of the installation. In the next step, within one hour the temperature was increased to 170aboutC. analysis of the gas at the inlet and the outlet of the installation during this period were made every 15 minutesAfter stabilization of the system at 170aboutWhen the hydrogen concentration in the gas at the inlet of the installation was set equal to the concentration of hydrogen in the gas at the outlet of the installation (0,5 about. %) produced a gradual increase in the concentration of the water installation has not reached the level of hydrogen concentration in the gas at the inlet of the installation (i.e., level 1 about. %). Then the concentration of hydrogen in nitrogen inlet installation for 2 h was gradually increased to about 5. %. This mode of operation was maintained up until the concentration of hydrogen in the gas at the input and output settings are not equal. In the next hour, the concentration of hydrogen in the same way was increased to about 10. %.After stabilization of the system when the concentration of hydrogen in nitrogen at 10 rpm. % when the concentration of hydrogen in the gas at the inlet and outlet installation is equalized, the concentration of hydrogen within the next hour was gradually increased to about 100. % and then the system pressure was increased to 28.6 bar. This pressure was maintained in the system for 3 h, and was completed the activation process of the catalyst.Upon completion of the activation process of the catalyst in the evaporator 2 with a bulk velocity of 0.15 m-1started feeding diethylmaleate. The temperature of the reactor was maintained at 170aboutC. the Molar ratio of hydrogen to air was 300:1. Analysis of the condensate and gas at the outlet of the installation showed that diethylmaleate easily converted into diethylamine, because in the reaction mixture containing diethylamine, gamma butyrolactone is UCA 2-ethoxyacrylate and 2-ethoxilated-1,4-diol, diethylmaleate not found. From the obtained results it was calculated that 98.2% of diethylamine obtained by hydrogenation of diethylmaleate as it passes through the layers odnokratnogo catalyst, is converted into products, i.e. in diethylamine, gamma-butyrolactone, butane-1,4-diol, tetrahydrofuran and water.Comparative example A.In the setup described in example 1, was loaded with 50 ml of granulated catalyst PG 85/1. Activation of the catalyst was made as follows.After crimping installed, it was purged with nitrogen at room temperature. The pressure of nitrogen in the plant was reduced to the level of 4.45 bar, and the nitrogen flow was reduced to hourly flow rate 3000 h-1, i.e., 150 l/h (measured at a temperature of 0aboutC and a pressure of 1 bar). The reactor was heated to 140aboutC. After temperature stabilization 140aboutWith nitrogen was added 0.2 to about. % hydrogen. After 48 h of operation in this mode, or when the concentration of hydrogen in nitrogen at the outlet of the installation was equal to the concentration of hydrogen in nitrogen at the entrance of the installation, if it happened earlier, the concentration of hydrogen in the nitrogen on the input set for at least 24 h was gradually the 24 hours the reactor temperature was maintained at 140aboutWith, and then was increased to 180aboutC and maintained at this level for 24 hours and Then the concentration of hydrogen in nitrogen inlet installation within 24 h was increased to 100%. Before using the catalyst it was aged in an atmosphere of hydrogen at a temperature of 180aboutWith in 12-24 hours For this process is the activation of the catalyst was completed.By repeating experimental hydrogenation as described in example 1, using activated as described above catalyst diethylmaleate (hourly space velocity in liquid form was 0,15 h-1) at a temperature of 170aboutWith the pressure of 28.6 bar and at a molar ratio of hydrogen to air 300 : 1 is also easily turned into diethylamine, but subsequent conversion into products (gamma-butyrolactone, butane-1,4-diol, tetrahydrofuran and water) was significantly lower and was 15.3%.The results show that the catalyst, the activation of which was carried out in accordance with the principles of the present invention, has a much higher activity compared to mediocrity catalyst, the activation of which is produced in the traditional way.P R I m e R s 2-4. Fragmentation of what smarami granules 2x2 mm 3 ml of this granular material was loaded into the reactor 6 setup (see drawing). For 30 min through the reactor 6 missed not containing oxygen, nitrogen. The nitrogen pressure at the inlet was installed 4,45 bar, and nitrogen flow was 200 l/h (measured at a temperature of 0aboutC and a pressure of 1 bar). Then you enter in the installation of nitrogen was added 0.2% of hydrogen, and the total gas flow was maintained at the same level. Within 2 h the temperature of the reactor 6 was gradually increased to 140aboutWith, and the concentration of hydrogen in nitrogen was maintained at the level of 0.2%. At this stage of the operation was carried out continuous monitoring of thermal conductivity of the gas at the inlet and outlet installation. After cessation of hydrogen absorption in the plant for approximately 24 h, the concentration of hydrogen is fed in nitrogen was gradually increased to 1%. After termination of the process of hydrogen absorption in the setting temperature of the reactor at a speed of 5aboutS/h was increased to 160aboutC. the reactor temperature was maintained for a further 4 hours Then the experiment proceeded as follows:
a) the concentration of hydrogen in nitrogen was gradually increased to 5% and this mode of operation is aboutWith this mode of operation was maintained for 4 h;
C) finally for 6 h concentration of hydrogen at the inlet of the plant has been increased to 100%. This mode of operation when the temperature of the catalyst 180aboutC was maintained for 18 hAfter this restorative treatment the catalyst was cooled by blowing him nesteriak oxygen with helium up to 80aboutC. the surface area of the metallic copper surface was determined by reaction of the recovered copper with nitric oxide at a temperature of 80aboutS, which can be represented by the equation:
2Cu+N2O _ C2O+N2< / BR>Assuming that the specific density of the monomolecular layer of copper is 1,h19atom/m2(this value is defined in article C. E. Sundquist published in the journal "Acta Met" N 12, S. 67, 1964), the degree of reaction, and, consequently, the number of absorbed on the surface of the copper atoms of oxygen can be determined by the sequential introduction of nitric oxide in helium until then, while the reaction will not stop that can be set in the absence of nitrogen in the eluate of the reactor.The experiments in examples 2 and 3 were made on the samples, the preliminary recovery of which was the op is melcene tablets. In table. 1 shows the relative consumption of nitric oxide and the corresponding values of the surface area of metallic copper.Comparative examples b and C.In the reactor 6 installation steps described in example 2, was placed in 3 ml granulated odnokratnogo catalyst PG 85/1 with granule size of 2x2 mm, which was prepared by crushing tablets.Through the reactor missed not containing oxygen, nitrogen, and the pressure at the inlet of the installation was maintained at the level of 4.45 bar and watch the volumetric rate of gas was 3000 h-1. Under these conditions the catalyst for 2 h was heated to 140aboutC. When the temperature of the catalyst has reached level 140aboutWith, to enter in the installation of nitrogen was added 0.2% of hydrogen. This mode of operation the system was maintained for 48 h until the disappearance of the absorption of hydrogen. Then within 24 hours the hydrogen fed to the reactor nitrogen was increased to 1%. The temperature of the catalyst within 24 h was maintained at 140aboutTo the disappearance of the absorption of hydrogen, which was determined by measuring the conductivity of the gas at the inlet and outlet installation. At the next stage of the experiment the temperature catalog in the next 24 hours Finally within 24 h the concentration of hydrogen fed to the reactor gas was increased to 100%. This mode of operation was maintained for 18 hA similar technique was applied in the comparative example, but the reactor 6 was loaded with 10 ml of unground catalyst PG 85/1 sizes of tablets 4,5x4,5 mmUsing a described in example 2 methods based on the reaction of nitric oxide were obtained the results presented in table.2.The comparison of these results indicates that the operation is keeping described in examples 2-4, provides a significant increase in surface area of copper.P R I m e R s 5-7. Earlier in the process studies on the adsorption of carbon monoxide on fully recovered hydrogen copper catalysts without the media it is shown that the adsorption of carbon monoxide is evident in the retention of a small amount of adsorbed gas on the open surface of copper. Similar studies using copper catalysts subjected to a small forced oxidation, showed that the adsorption of carbon monoxide at 20aboutWith leads to the formation of a certain amount of carbon dioxide in rezultatai 3 ml were subjected to restoration method described in example 2, after which the samples for 1 h were cooled to 20aboutWith using nestorgames oxygen helium. Then in the gas flow over the catalyst pulses were injected 10% carbon monoxide. The eluate from the reactor was passed through a cooled nitrogen trap for freezing is present in the eluate of carbon dioxide. Using thermal conductivity detector out of a trap the eluate was analyzed for the presence of carbon monoxide. The use of pulsed feed of carbon monoxide is allowed to determine the amount adsorbed by the catalyst of carbon monoxide, which in General did not exceed 10% of the maximum value of adsorbed carbon monoxide at saturation monomolecular layer in a static system.Upon completion of the adsorption process cooled trap was warmed to determine the number of formed carbon dioxide. Thereafter, the catalyst was subjected to a desorption treatment according to a certain program changes the temperature optimum for heating the catalyst at a rate of 10aboutC/min with simultaneous registration of the desorption spectrum of adsorbed material. On desorption spectrum revealed two peaks, one - on t is of less height at temperatures 300-320aboutWith characteristic adsorption of carbon monoxide in the form of carbon dioxide on the media, which represents an oxide of chromium.The results of adsorption and programmed temperature desorption are given in table. 3. All adsorption measurements were performed at 20aboutC.It should be noted that in each of examples 5-7 were not detected education of carbon dioxide in the process of adsorption of carbon monoxide, which points to the fact that the method of recovery of the catalyst described in example 2, provides complete recovery of the catalyst.Comparative examples D and E.Using three different catalyst subjected to restoration processing in accordance with the comparative example In methods, it is impossible with the use of adsorption-desorption technique described in examples 5-7, a quantitative evaluation of the process of adsorption of carbon monoxide due to the continuous recovery of the catalyst, although it is obvious that some absorption of carbon monoxide was observed. However, it should be noted that when the pulse passing carbon monoxide over a catalyst, the formation of the TLD is RNA desorption shows the presence on the catalyst surface a quantity of adsorbed carbon monoxide. The results of the experiment are given in table. 4.A noticeable difference in performance in relation to carbon monoxide between the catalyst recovery processing as described in example 2 and the catalyst recovery processing as described in comparative example shows that when the recovery of the catalyst by the method described in the comparative example, on the surface of the copper remains a significant amount of oxygen. The values of the output of carbon dioxide the amount covered by the oxygen of the copper surface after activation of the catalyst with hydrogen according to the method described in comparative example B, is not less than 5% of the total surface of copper, which is determined by the decomposition of nitric oxide.The presence of oxygen on the copper surface after restoration processing of the catalyst is confirmed also obtained when programmatically changing the desorption temperature range, which indicates that the carbon monoxide (peak at a temperature of 110about) Is retained on the catalyst more firmly than is observed in the case of adsorbed carbon monoxide to the catalyst subjected to the reduction process described in example 2 (see tab. 3).P R and m is istemi copper/zinc oxide/aluminum oxide can be used for reliable monitoring of the lack of surface oxygen on the copper component by dissociative chemisorption before the formation of carbon monoxide at moderate temperatures in the absence of hydrogen, that avoids the possibility of changing the ratio of carbon monoxide and hydrogen in the water gas. This method was used with the catalysts subjected to the reduction process described in example 2, in order to reconcile the data obtained during the measurements of the adsorption of carbon monoxide, as described in examples 5-7.During the experiment, the gas flow over the catalyst was periodically injected a small dose of carbon dioxide and the absorption of carbon dioxide was determined on the basis of measurements of thermal conductivity of the gas at the inlet and outlet installation. After reaching adsorption of carbon dioxide level of saturation of the catalyst was subjected software thermal desorption in a stream of helium at a heating rate of 5aboutC/min until a temperature of 220aboutC. the results of the experiment are given in table. 5.From the above table. 5 data on desorption peak of the spectrum at 90aboutSince it is obvious that the recovered catalyst, having in mind the fact that the oxygen on the surface of copper newly restored catalyst is absent, there is a significant dissociation of carbon dioxide. The absorption of carbon dioxide by these catalysts is somewhat higher for the soup in the composition of the catalyst of chromium oxide. Comparison of the amounts of carbon monoxide desorbitadas covered with carbon dioxide surfaces and quantities of adsorbed carbon monoxide (see table. 3) indicates that approximately 25% of the total surface adsorption of carbon monoxide is carbon monoxide formed by dissociative adsorption of carbon dioxide.No studies of the adsorption of carbon dioxide on the catalyst described in comparative example B, was not made, because it seems incredible that you can detect the difference between carbon dioxide adsorbed on partially oxidized copper, and carbon dioxide adsorbed on a part of the catalyst is chromium oxide.P R I m e R 9. The study of the distribution of particle sizes of the catalysts subjected to restoration processing described in example 2 was carried out using a transmission electron microscope. After restoration processing described in example 2, the catalyst in the flow nestorgames oxygen helium was cooled to room temperature. Then the reactor was purged nesteriak oxygen, nitrogen and extracted from the reactor, the catalyst was quickly placed in deionized Vody to minimize contact of the sample with the surrounding atmosphere. As indicated below, some of the samples initially before examination with a scanning electron microscope were subjected to investigation on the adsorption/desorption.In the study of microphotographs, which is typical of several obtained for each sample micrographs, it is clear that in relation to the particle size of the recovered copper between samples of catalysts subjected to activation by the method described in example 2, and examples of catalysts subjected to activation by the method described in the comparative example, there are very noticeable differences. Copper particles appear as dark areas on a bright background, the corresponding amorphous chromium oxide in the role of the media.Due to the difficulty of ensuring sufficient contrast, due to the proximity of the atomic number of chromium and copper and opacity echinochrome media, it is impossible to analyze the entire distribution of particle sizes of the samples, however, it is possible to estimate the size ranges of particles of each catalyst (see table. 6). From the above table. 6 data shows that the average particle size of copper in the catalysts obtained by the methods described in eleet obvious, the dimensions and geometry of the particles of the catalysts embodying the principles of the present invention, in the process of restoration processing is not applied, and the range of particle sizes and the average particle size for unground catalyst corresponds exactly to the range of particle sizes and the average size of the particles for catalyst crushed to granules with sizes of approximately 2x2 mm, it is also Clear that the catalysts embodying the principles of the present invention, are characterized by sufficient heat resistance to temperatures above 220aboutC.P R I m e R 10. To explore possible differences between restorative processes described in example 2 and comparative example, in relation to recovery magnochromite catalysts at temperatures below the initial temperature of the process of restoration processing described in the comparative example, which may be reflected in a large difference between the results of the process described in comparative example, and the process described in example 2, was made two experiments with different programs temperature changes in the recovery process odnokratnogo catalyst. In these expence temperature 18-650aboutWith increased speed 30aboutC/min, and in another experiment with a speed of 50aboutC/min In both experiments it was determined that any appreciable absorption of hydrogen at temperatures below 140aboutWith does not occur even in the case of a relatively slow increase in temperature. In experiments it was established that in both cases, the characteristics of the recovery process has a single peak at Tmax= =215aboutFor low speed increasing the temperature, Tmax=370oC for high speed temperature increase, which means that the recovery of chromite occurs as a result of the recovery of copper oxide.For cases of high and low speed increasing the temperature of the absorption of hydrogen was 9430 and 1083 LFM/g, respectively.P R I m e R 11. In the reactor of a pilot installation for the implementation of the hydrogenation of diethylmaleate in the vapor phase in accordance with the method [1, 5], was loaded mediocrity catalyst PG 85/1 with granule size 4,5x4,5 mm Loaded in the reactor the catalyst was located in two layers, the first of which had a depth of 1.83 m and the other of 0.91 m Catalyst was subjected to a preliminary restoration in a manner analogous to opisane used for hydrogenation of diethylmaleate for 2000 h under a variety of operating modes. During operation the gas pressure in the reactor ranged from 13.8 to 41.3 bar, and the molar ratio of hydrogen to air in the range from 200 : 1 to 400 : 1. The temperature at the inlet of the first catalyst layer was maintained in the range 160-175aboutS and inlet temperature of the second catalyst layer is in the range 170-180aboutC. the Supply of liquid ether in the pilot installation was performed from the time the volumetric rate of 0.15 h-1. The product of the hydrogenation process was a mixture of butane-1,4-diol, gamma-butyrolactone and tetrahydrofuran, plus a small number of products, including diethylethanolamine and n-butanol. The catalyst, having initially high activity, was subjected to comparison in the working conditions with the catalyst before contacting with hydrogen was heated to 140aboutC in nitrogen atmosphere. Over time there was a slight decrease in the activity of the catalyst. At the end of the working cycle of the two layers of catalyst was cooled in a stream of hydrogen to room temperature, after which the hydrogen has been displaced from the system with nitrogen, which was accompanied by the introduction of the nitrogen system incorporating 2% oxygen. This mixture was formed by adding to the stream of nitrogen, predispo reduction of the temperature gradient along the height of the catalyst to zero, in the feed reactor gas began a gradual introduction of air while reducing the feed to the reactor nitrogen. This process continued until until all are fed into the reactor, the nitrogen was replaced by air.Thus obtained is re-oxidized material was subjected to grinding particles with dimensions of approximately 2x2 mm, and then he was previously restored by the method described in example 2. The method described in example 2, measurements were made of the surface area of metallic copper. The results obtained were similar to the results shown in example 2. In addition, the study re-recovered catalyst by using a transmission electron microscope by the method described in example 9, it was found that the sizes of all particles of metallic copper are within approximately h-10m (about 30 ) to h-10m (about 300 ), and the average particle size is approximately h-10m (about 50 ).P R I m e R 12. Again the reduced catalyst prepared by the method described in example 11 was subjected to the tests on the catalytic activity similar to that described in example 1. Set derrotou comparison with the activity of the catalyst, described in comparative example A.P R I m e p 13. Re-restored the catalyst described in example 11 was subjected to preliminary restoration of the traditional method described in comparative example A. In determining the activity repeatedly recovered catalyst by methods described in example 1 and in comparative example A, it was found that the defined catalytic activity closer to the activity previously vosstanovlenie on catalyst described in example 1, and higher activity previously recovered catalyst described in comparative example A.P R I m e R 14. The experiments described in example 1 and comparative example a were re-produced from different source magnochromite catalysts, which had the following chemical composition: Catalyst X (wt. %) 53 copper, 17 chromium atomic ratio of Cu : Cr is 2.5 Y Catalyst (wt. %) 36,2 copper, 30 chromium atomic ratio of Cu : Cr is 1.21 Catalyst Z (wt. %) 36,2 copper, 30 chromium, 10 oxide of barium.These catalysts were obtained results similar to the results for catalyst PG 85/1.P R I m e R s 15-20. The catalyst described tea at the tabulated conditions were obtained satisfactory results.P R I m e R 21. The catalyst described in example 1 was used to dehydrogenization ethanol to acetaldehyde at a pressure of 1 bar and a temperature of 270aboutC. the Process was characterized by a high product yield. CATALYST FOR HYDROGENATION OF UNSATURATED COMPOUNDS AND THE METHOD OF ITS PREPARATION.1. Catalyst for hydrogenation of unsaturated compounds containing the recovered copper-chromite composition of the copper particles, uniformly distributed over the surface of amorphous chromium carrier, characterized in that, to increase activity of the copper particles have a size (30 - 300) 10-1m with an average particle size of 50 10-10m and a surface area, determined by decomposition at 80oWith nitrous oxide (I) equal to 18,36-18,61 m2/,2. The catalyst p. 1, characterized in that the catalyst contains copper and chromium atomic ratio of 1.2 to 2.5:1.3. Catalyst under item 1 or 2, characterized in that it additionally contains 10 wt.% barium oxide.4. The preparation method of catalyst for hydrogenation of unsaturated compounds recovery of copper-chromite compositions by treating the composition with the stream of nitrogen to follow the and hydrogen and temperature recovery for regulated restore options characterized in that, in order to obtain the catalyst of increased activity, the addition of hydrogen to begin at ambient temperature, the temperature of the restoration carried out by adjusting the composition of the gases at the inlet and outlet so that the compositions of the gases at the inlet and outlet were practically identical to each other, and the catalyst is kept in a reducing atmosphere until a temperature recovery 140-180oC.5. The method according to p. 4, characterized in that the curing catalyst in a reducing atmosphere is carried out at a total gas pressure of 4.45 bar and a partial pressure of hydrogen 0,009-0,023 bar.6. The method according to PP.4 and 5, characterized in that rising temperatures are from ambient temperature to 120oWith variable speed of 10 deg/h when the concentration of hydrogen in the gas flow of 0.2-0.5% vol.7. The method according to PP.4-6, characterized in that the temperature increase is carried out in the range of 120-170oWith linear speeds of 5 - 10 deg/h8. The method according to PP.4-7, characterized in that the temperature increase in the range of 120-170oTo carry out when the gas flow with a bulk velocity, designed for temperatures 0oAnd Yes
FIELD: hydrogenation-dehydrogenation catalysts.
SUBSTANCE: invention relates to catalysts used in isoamylenes-into-isoprene dehydrogenation process and contains, wt %: iron oxide 62-75.4, potassium carbonate 12-21.5, chromium oxide 1-3, potassium hydroxide 0.5-2.5, sulfur 0.1-2.0, ammonium nitrate 0.1-2.0, silicon dioxide 1-5, calcium carbonate 1-5, and cerium nitrate 1-3.
EFFECT: increased mechanical strength, resistance to saturated steam and moisture, and stability during long-time operation.
FIELD: inorganic synthesis.
SUBSTANCE: iron-chromium-nickel spinels are prepared by homogenization of original oxides of nickel(II), iron(III), and chromium(III) in presence of 0.5-1.5% of potassium halides as mineralizing agent followed by briquetting and heat treatment of oxides at 800-1000°C.
EFFECT: enabled preparation of spinels at lowered temperatures and in shorter time.
2 tbl, 2 ex
FIELD: organic synthesis catalysts.
SUBSTANCE: invention provides improved method for preparing catalyst for synthesis of N-methylaniline from aniline and methanol. Method comprises impregnation of alumina carrier with copper nitrate solution, to which were added nitrates of modifying metals selected from group consisting of manganese, chromium, iron, cobalt, and zinc, after which impregnated carrier is dried at temperature ensuring effective conversion of deposited nitrates into oxides of corresponding metals. When calcined, catalyst is subjected to additional impregnation with copper ammine solution, wherein Cu content (on conversion to oxide) lies within 0.6 to 7.0% based on the weight of catalyst, then dried at 100-120°C, and re-calcined at 230-250°C. After first calcination Cu content is 10.1-13% and after the second it rises by 0.6-5.0%. Lifetime of catalyst increases by a factor of 1.3 to 2.
EFFECT: increased lifetime of catalyst.
1 tbl, 12 ex
FIELD: industrial organic synthesis catalysts.
SUBSTANCE: invention relates to copper-containing catalysts for low-temperature synthesis of methanol in fluidized bed at median pressure and provides catalyst, whose preparation involves impregnation and which contains oxides of copper, zinc, chromium, magnesium, aluminum, boron, and barium and has following molar ratio: CuO:ZnO:Cr2O3, MgO:Al2O3:B2O3:BaO = 1:0.3:(0.014-0.038):(0.047-0.119):(0.05-0.1):(0.007-0.014):(0.0292-0.054).
EFFECT: increased mechanical strength and wear resistance of catalyst.
FIELD: industrial organic synthesis catalysts.
SUBSTANCE: invention relates to copper-containing catalysts for low-temperature synthesis of methanol in fluidized bed at low pressure and provides a wear-resistant catalyst, whose preparation involves impregnation and which contains oxides of copper, zinc, chromium, magnesium, aluminum, and boron and has following molar ratio: CuO:ZnO:Cr2O3, MgO:Al2O3:B2O3 = 1:0.3:(0.15-0.2):(0.1-0.025):(0.25-0.3):(0.08-0.1).
EFFECT: increased mechanical strength and wear resistance of catalyst.
FIELD: industrial organic synthesis catalysts.
SUBSTANCE: invention relates to copper-containing catalysts for low-temperature synthesis of methanol in fluidized bed at high pressure and provides catalyst, whose preparation involves impregnation and which contains oxides of copper, zinc, chromium, magnesium, aluminum, boron, and barium and has following molar ratio: CuO:ZnO:Cr2O3, MgO:Al2O3:B2O3:BaO = 1:(0.7-1.1):(0.086-0.157):(0.05-0.15):(0.125-0.2):(0.018-0.029):(0.04-0.075).
EFFECT: increased mechanical strength and wear resistance of catalyst.
FIELD: composition and structure of composite metal semiconductor meso-porous materials; titanium-dioxide-based catalyst for photo-chemical reactions.
SUBSTANCE: proposed catalyst is meso-porous titanium-dioxide-based material containing crystalline phase of anatase in the amount no less than 30 mass-% and nickel in the amount no less than 2 mass-%; material has porous structure at average diameter of pores from 2 to 16 nm and specific surface no less than 70 m2/g; as catalyst of photo-chemical reaction of liberation of hydrogen from aqua-alcohol mixtures, it ensures quantum reaction yield from 0.09 to 0.13. Method of production of such catalyst includes introduction of precursor - titanium tetraalkoxyde and template of organic nature, holding reagent mixture till final molding of three-dimensional structure from it at successive stages of forming sol, then gel, separation of reaction product and treatment of this product till removal of template; process is carried out in aqua-alcohol solvent containing no more than 7 mass-% of water; at least one of ligands is introduced into solvent as template; ligand is selected from group of macro-cyclic compounds containing no less than four atoms of oxygen and/or from complexes of said macro-cyclic compounds with ions of metals selected from alkaline or alkaline-earth metals or F-metals containing lithium, potassium, sodium, rubidium, cesium, magnesium, calcium, strontium, barium, lanthanum and cerium; mixture is stirred before forming of sol maintaining its temperature not above 35°C till final molding of three-dimensional structure from reagent mixture; mixture is held in open reservoir at the same temperature at free access of water vapor; after removal of template from three-dimensional structure, mixture is first treated with nickel salt solution during period of time sufficient for withdrawal of nickel ions from solution by pores of structure, after which is it kept in hydrogen-containing medium during period of time sufficient for reduction of nickel ions in pores of structure to metallic nickel.
EFFECT: enhanced sorption and photo-catalytic parameters; reproducibility of catalyst properties.
7 cl, 68 ex
FIELD: methods of production of spinels in chemical industry for production of catalysts.
SUBSTANCE: proposed method of production of nickel ferrite-chromite (II) having structure of spinel includes homogenization of initial material mixture containing nickel (II) oxide, chromium (IV) oxide and dihydrate ferrous oxalate (II). Mixture thus obtained is briquetted and is subjected to heat treatment at temperature of 800-1000°C.
EFFECT: reduction of temperature and duration of process.
1 dwg, 1 tbl, 1 ex
FIELD: disproportionation process catalysts.
SUBSTANCE: invention relates to generation of hydrogen through steam conversion of carbon monoxide and development of catalyst for indicated process. Invention provides carbon monoxide conversion catalyst showing high catalytic activity and heat-conductivity and a process of steam conversion of carbon monoxide using indicated catalyst. Catalyst is characterized by heat-conductivity at least 1 W(mK)-1, which enables performing process with low temperature gradient in direction transversal to gas stream direction.
EFFECT: increased catalytic activity and heat-conductivity.
7 cl, 4 dwg, 3 tbl, 10 ex
FIELD: shift reaction catalysts.
SUBSTANCE: invention relates to iron oxide-containing catalysts generally used for high-temperature shift reactions wherein gas stream containing water steam and carbon monoxide is passed over catalyst at temperature within a range of 350 to 550°C to convert carbon monoxide into carbon dioxide with simultaneous formation of hydrogen. Catalyst is prepared via precipitation of composition containing ferrous and ferric iron and chromium(III) with a base, ferrous iron being partly oxidized by an oxidant into ferric iron. Further formation of resulting precipitate into formed catalyst blocks is effected at temperature above 200°C. Invention also provides a high-temperature shift reaction process using above catalyst blocks.
EFFECT: avoided need of catalyst restoration stage resulting in improved catalyst strength and activity.
10 cl, 2 tbl, 2 ex
FIELD: hydrogenation-dehydrogenation catalysts.
SUBSTANCE: palladium-containing hydrogenation catalyst, which can be used to control rate of autocatalytic hydrogenation reactions, is prepared by hydrogen-mediated reduction of bivalent palladium from starting compound into zero-valence palladium and precipitation of reduced zero-valence palladium on carbon material, wherein said starting material is tetraaqua-palladium(II) perchlorate and said carbon material is nano-cluster carbon black. Reduction of palladium from starting compound and precipitation of zero-valence palladium on carbon material are accomplished by separate portions.
EFFECT: increased catalytic activity, enabled catalyst preparation under milder conditions, and reduced preparation cost.
1 dwg, 1 tbl, 12 ex
FIELD: petrochemical processes.
SUBSTANCE: feedstock is brought into contact with preliminarily activated zeolite-containing catalyst, namely mordenite-supported Pt, at 250-300°C, pressure 1.5-3.5 MPa, hydrogen-containing gas-to-feedstock ratio 300-1000 nm3/m3, and feed flow rate 1.0-4.0 h-1. Preliminary activation of zeolite-containing isomerization catalyst is conducted in two successive steps: drying catalyst in inert gas flow; reducing catalyst in hydrogen-containing gas flow; and supplying feedstock and setting steady-state isomerization process. Drying of zeolite-containing catalyst in inert gas flow is effected under conditions of gradually raised temperature from 120°C at temperature raise rate 10-15°C/h and ageing for 2-5 h at 120°C to 350°C followed by ageing at this temperature, whereupon temperature is lowered to 130°C. Reduction of zeolite-containing catalyst in hydrogen-containing gas flow is effected at gradually raised temperature to 220-350°C at temperature rise rate 15-25°C/h and ageing for 2-6 h at 220-350°C, whereupon temperature is lowered to 180°C. Initial feedstock is supplied at 180°C in circulating hydrogen-containing gas flow, aged for 4 h at 180°C and then gradually heated to 250°C at heating rate 5°C/h, after which further heated at heating rate 5°C a day to achieve process characteristics meeting product quality requirements.
EFFECT: increased catalyst activity, selectivity, and working stability.
2 cl, 2 tbl, 17 ex
FIELD: petroleum processing and petrochemistry.
SUBSTANCE: catalytic system of hydrocarbon feedstock hydrofining is activated by circulating hydrogen-containing gas or mixture thereof with starting feedstock through layer-by-layer loaded catalysts in presulfided or in presulfided and oxide form at elevated temperature and pressure. Hydrogen is injected into circulating hydrogen-containing gas or mixture thereof with starting feedstock portionwise, starting concentration of hydrogen in circulating hydrogen-containing gas not exceeding 50 vol %. Starting feedstock consumption is effected stepwise: from no more than 40% of the working temperature to completely moistening catalytic system and then gradually raising feedstock consumption to working value at a hourly rate of 15-20% of the working value. Simultaneously, process temperature is raised gradually from ambient value to 300-340°C. Circulating factor of hydrogen-containing gas achieves 200-600 nm3/m3. Addition of each portion of hydrogen is performed after concentration of hydrogen in circulating hydrogen-containing gas drops to level of 2-10 vol % and circulation of hydrogen-containing gas through catalysts loaded into reactor begins at ambient temperature and further temperature is stepwise raised. Starting feedstock, which is straight-run gasoline or middle distillate fractions, begins being fed onto catalytic system at 80-120°C.
EFFECT: enabled prevention and/or suppression of overheating in catalyst bed.
5 cl, 6 tbl, 12 ex
FIELD: hydrocarbon conversion processes.
SUBSTANCE: process consists in catalytic decomposition of hydrocarbon-containing gas at elevated temperature and pressure 1 to 40 atm, catalyst being reduced ferromagnetic cured product isolated by magnetic separation from ashes produced in coal combustion process at power stations. The catalytic product represents spinel-type product containing 18 to 90% iron oxides with balancing amounts of aluminum, magnesium, titanium, and silicon oxides. Prior to be used, catalyst is subjected to hydrodynamic and granulometric classification.
EFFECT: reduced total expenses due to use of substantially inexpensive catalyst capable of being repetitively used after regeneration, which does not deteriorate properties of original product.
2 cl, 6 ex
FIELD: hydrogenation-dehydrogenation catalysts.
SUBSTANCE: invention provides copper and silica-based catalyst containing 22.5-53.0% copper. Catalyst is prepared by reductive thermal decomposition of copper silicate in hydrogen flow at 380-450°C. catalyst is used in dihydroxyalkane production processes carried out at 180-200°C.
EFFECT: increased activity and selectivity of catalyst.
3 cl, 1 tbl, 8 ex