The method of activation medetinskogo the catalytic hydrogenation of aldehydes
(57) Abstract:Describes how to activate medetinskogo catalyst - catalyst brand NTK-U (L), used for the hydrogenation of aldehydes and / or their mixtures with other carbosilane obtained in the process of hydroporinae propylene, which includes treatment of the catalyst at elevated temperature and pressure circulating at a speed of 500 - 4000 h-1nitrogen and hydrogen. At the initial stage handle catalyst circulating nitrogen under a pressure of 20 to 80 ATM, uniformly increasing temperature for 15 to 20 hours up to 300 - 350oC, at which maintain the catalyst within 6 - 12 h, then the catalyst was cooled to 170 - 230oC, the pressure of the circulating nitrogen up to 20 to 150 ATM and gradually replacing the hydrogen with the initially selected pressure and rate of gas circulation, followed by exposure of the catalyst after complete replacement of nitrogen to hydrogen in these conditions for 15 - 18 hours Technical result is an increase in selectivity and activity of the catalyst, increasing the length of the catalyst in the optimal temperature range and a longer service life of the catalyst. 3 C.p. catalysts for the hydrogenation of aldehydes to alcohols.In industry the process of hydrogenation of aldehydes C4received by the propylene hydroformylation, is carried out at a temperature of 200-300oC and a pressure of 200-300 bar for a Nickel - or copper-containing catalysts, then using a rectification produce target products - butyl alcohols normal or isotrate.As the industrial practice, the most high technical and economic indicators of the process of hydrogenation of aldehydes and their mixtures with other products of propylene hydroformylation achieved using medetinskogo catalyst stamps STC-1 (modern analogues NTK-U and NTK-U (D) composition, wt.%: the copper oxide 11-14, chromium oxide 21-25, zinc oxide 50-54, aluminum oxide 4-5, magnesium oxide 1,5-2, manganese oxide 1,5-2, graphite else. However, a significant role in determining the efficiency of the catalyst in the above process (activity, selectivity and stability), plays the way its activation procedures preparation and transfer of catalyst from the oxide form in which it is produced, in a restored, working condition. (THE 113-03-00203815-85-95).Known methods of recovery mediacentertopic catalysts to processcolor restoration of oxygen-containing compounds of copper, included in the catalyst composition type NTC, accompanied by a significant and difficult-controlled heat, to prevent accidents, sintering of catalysts and active recovery conduct diluted hydrogen-containing gas at pressures close to atmospheric, slowly raising the temperature to 180-260oC and gradually increasing the concentration of hydrogen in the gas from 0.3 to 0.5% in early recovery to 100% in the end. As a reducing gas is a mixture of hydrogen with nitrogen, CO, CO2CH4water vapor (ammonia Production" Ed. by B. N. Semenov, M., "Chemistry", 1985, S. 94-96, 135).Similarly activate and metrogroove catalysts for the hydrogenation of aldehydes. So there is a method of recovery metrogroove catalyst for hydrogenation of unsaturated aldehydes, lies in its treatment of circulating an inert gas at 80-130oC and a pressure of 0.1 to 1.5 MPa for 5-40 hours with a gradual replacement of the inert gas with hydrogen gas containing water vapor in a quantity of 0.05 to 0.3 wt. % while increasing the temperature up to 150-180oC and then aged at this temperature for 5-50 h (SU 1209273, 07.02.86).In addition to these spam recovery mediacentertopic catalysts at relatively high pressures. By the way, the most similar to that proposed by the technical nature, to increase the service life synchronuos catalyst in processes for the hydrogenation of carbonyl compounds, its activation is carried out by treatment with a nitrogen circulating under pressure 150-250 ATM with the speed of 700-4000 h-1uniformly increasing the temperature to 180oC for 6-8 hours after reaching the specified temperature in the circulating nitrogen begin with speed 10-60 h-1the dosing of hydrogen, while maintaining the temperature in the catalyst bed in the range 180-195oC. 35-40 hours processing diluted in this way the hydrogen-containing gas recovery complete (SU 1397074, 23.05.88).Recovered by known methods odnotsentovuyu catalysts are sufficiently active and stable, but have the common disadvantage is the relatively low selectivity: output products further reactions of aldehydes is 5-10%.It is known that one of the major factors determining the selectivity of heterogeneous catalyst, is its porous structure. So nonoptimality of the patterns produced by industry nickelchromium catalysts applied in the reaction of Hydra the eve of the reaction with a slight deviations from the set temperature in the hydrogenation reactor. To optimize the structure nickelchromium catalyst and thereby increasing its selectivity, the authors have proposed a method of thermal modification of the catalyst (SU 445234, 1976).This process is most similar to that proposed by the achieved effect, nickelchromium the catalyst used for hydrogenation of aldehydes in the butyl alcohols, immediately before used in addition to standard procedure dovolenkovania at 120-180oC (catalyst produced by the manufacturer in the restored and passivated form) is subjected to further treatment with hydrogen at 420-480oC. as a result of this change substantially porous structure of the catalyst: there is a sharp decrease in the specific surface area 180 m2/g (source) to 25-40 m2/g (ready for use in the process of catalyst). This procedure allows to obtain the most selective catalyst for the hydrogenation of aldehydes in butyl alcohol.The present invention is to develop an effective way of activating medetinskogo catalyst containing oxides of aluminum, magnesium and manganese - catalyst brand NTK-U (what inanami (esters, acetals) in butyl alcohol. The purpose of the invention is to improve the selectivity of the catalyst.The objective according to the invention is achieved as follows. The catalyst NTK-U (D) for the hydrogenation of mixtures of aldehydes and other carbonyl-containing compounds obtained after the stage of demobilization products of propylene hydroformylation, placed in a hydrogenation reactor and treated with nitrogen, circulating under pressure 20-80 atmospheres with a bulk velocity 500-4000 h-1uniformly increasing the temperature up to 300-350oC for 15-20 hours. In this temperature range and the current circulating nitrogen, the catalyst can withstand 6-12 hours, and then cooled to a temperature of 170-180oC, at which start processing catalyst hydrogen-containing gas: in the circulating nitrogen start pulse, small portions to dispense hydrogen. The frequency of submission of samples of hydrogen and the amount of control, registering the temperature in the catalyst bed, which should be in the range 170-230oC, and measuring the hydrogen concentration in the circulating gas. When the catalyst layer detects a leakage of hydrogen, begin to increase its concentration in the circulating gas at a rate of 0.5-thanaweya water. When reaching the hydrogen content in the gas 96-99 about. % withstand the catalyst for another 15-18 hours, after which the activation of the stop. Prepared according to the procedure of catalyst used in the process of hydrogenation of aldehydes and other products of oxosynthesis.Salient features of the proposed method are: the prior (before filing a reducing gas) processing stage catalyst circulating nitrogen under pressure 20-80 atmospheres and at a temperature of 300-350oC for 6-12 hours; the restoration of the oxide phase of catalyst in the temperature range 170-230oC by pulsed supply in a nitrogen circulating under pressure 20-80 atmospheres with the speed of 500-4000 h-1with the gradual complete replacement of nitrogen in the circulating gas to hydrogen.The obviousness of the proposed method is proved as follows.According to the method prototype activating synchromesh catalysts containing the oxides of copper, aluminum, calcium, magnesium, carried out by preliminary uniform, 180oC, heating the catalyst in the circulating current with a speed of 700-4000 h-1under the pressure of 150-250 ATM of nitrogen with subsequent quenching and the feeding speed: nitrogen 700-4000 h-1, hydrogen 10-60 h-1).According to the method similar recovery apromotional metrogroove catalyst is carried out by gradual replacement of circulating at a temperature of 80-130oC and a pressure of 0.1 to 1.5 MPa of nitrogen to hydrogen containing water vapor in a quantity of 0.05 to 0.3 wt.%, and simultaneous increase of the temperature up to 150-180oC.Additional processing nickelchromium catalyst for the hydrogenation of aldehydes to optimize its porous structure and selectivity enhancement process is carried out with hydrogen at 400-800oC. Such a treatment is carried out after the initial recovery of the catalyst. Thus there is a decrease in the extent of its surface with 180 m2/g to 25-40 m2/year For the proposed method processing medetinskogo the catalytic hydrogenation of aldehydes is carried out using nitrogen at 300-350oC and prior to the filing of a reducing gas. In this case, as shown by special studies (see example 2), there is no reduction, and growth of the catalyst surface from 13 to 35 m2/g and an increase in its activity and selectivity.The advantage of the proposed method is to obtain a restore is soedinenii - products of propylene hydroformylation with increased selectivity. In addition, there has been and increase in the activity of the catalyst (additional effect), thereby reducing the total pressure at the stage of hydrogenation of from 150-250 ATM to 20-80 atmospheres and to carry out both stages of the process of the hydrogenation of aldehydes (preparation of the catalyst and the raw material cycle) in the same interval of the applied pressure. However, judging by the values of the conversion of the starting products and the yield of the target in time (see example 5), activated by the proposed method, the catalyst is sufficiently stable when working on real industrial raw materials.Industrial application of the proposed method is illustrated by the following examples.Example 1
Three of the same sample of catalyst NTK-U (L) corresponding to THE 113-03-00203815-85-95, crushed to the size of 1-2 mm and a volume of 20 cm3everyone loaded into the reactor laboratory flow-through units. Each sample is subjected to activation
The first sample restore by a known method, proposed similar: the catalyst is heated at a rate of 10oC per hour in nitrogen at pressures of 0.1 MPa and a feed rate of the nitrogen 1500 h to 120oC. after 4 hours ichiwa the temperature and the concentration of hydrogen in the feed gas. At a temperature of 180oC and the content of hydrogen in the reducing gas mixture of 98% vol. stand the catalyst 18 hours, then finish.A second sample will activate according to the method proposed in the prototype: the catalyst evenly, within 8 hours heated to a temperature of 180oC in the current circulating under pressure of 150 ATM with a speed of 3000 h-1of nitrogen. On reaching this temperature in the circulating nitrogen added at a rate of 10 - 60 h-1hydrogen, maintaining the temperature in the catalyst bed 180-195oC. At this temperature, and the current circulating nitrogen-hydrogen mixture stand the catalyst 40 hours, after which the activating end.The third sample is restored by the proposed method: the catalyst for 20 hours, treated with nitrogen under a pressure of 20 ATM at a speed of gas flow 500 h-1uniformly increasing the temperature to 320oC. At this temperature, maintain the catalyst in a stream of nitrogen for 6 hours, then stop the heating of the reactor, cool the catalyst to 180oC. Upon reaching this temperature in a stream of nitrogen begin in small portions to dispense hydrogen. The concentration of hydrogen in a stream of nitrogen post the e catalyst 180-230oC. At this temperature the catalyst is kept in a current of hydrogen for 15 hours, after which the activation cease.All three prepared as mentioned above sample of the catalyst was tested for activity. To do this, in the reactor of each facility serves 10 cm3/h technical samalanga aldehyde and 30 l/h of hydrogen. In reactors maintain a pressure of 20 ATM and a temperature of 180-185oC. the hydrogenation product is cooled to room temperature and analyzed by gas-liquid chromatography method. In table. 1 presents the results of these experiments. It can be noted that the catalyst activated by the proposed method showed the highest activity and selectivity in comparison with samples that have been activated by means of the prototype and similar.Example 2
The example illustrates the selection of the optimal temperature pre-treatment of the catalyst with nitrogen before starting the supply of hydrogen.Five samples of catalyst NTK-U (L), the fraction 1-2 mm, 20 cm3everyone is placed into the reactor laboratory flow-through setup and heated to the temperature of the experience (for each sample has its own) in a stream of nitrogen supplied under a pressure of 20 ATM with a speed of 2000 h-Razza one of the 200, 250, 300, 350 or 400oC) they are matured for 9 hours after which the reactor is cooled to 180oC. Upon reaching this temperature in a stream of nitrogen begin in small portions to dispense hydrogen. The concentration of hydrogen in the nitrogen gradually, from 5 to 10 vol.% per hour increase to full replacement of nitrogen to hydrogen (chromatographic control), keeping the temperature in the catalyst bed 180-230oC. At this temperature, each sample of the catalyst incubated for another 10 hours, after which the activation of the stop. Recovered samples of the catalyst was tested in the same setup on the activity in hydrogenation reactions samalanga aldehyde in the following conditions: volumetric feed rate of the aldehyde 0.5 h-1, the molar ratio of hydrogen : aldehyde is 10, the temperature in the reactor 180oC, a pressure of 20 ATM. The reaction products using the sampler serves for analysis on the GC.After testing the activity of installing blown off with nitrogen and the catalyst in a stream of nitrogen overload without contact with air in the installation to determine the specific surface area. Thus for each sample receive data on its activity, selectivity and porous structure, which shows usator NTK-U (D) circulating the nitrogen has a significant impact on the value of the specific surface of the catalyst and the associated selectivity of the conversion of the aldehyde. The most developed surface and selectivity of catalysts have designed in a stream of nitrogen at a temperature of 300-350oC.Example 3
The example illustrates the selection of the optimal duration of the exposure time of the catalyst in a stream of nitrogen at temperatures of 300-350oC prior to treatment with hydrogen. Five samples of catalyst NTK-U (D) in turn heated in a stream of nitrogen, supplied with a speed of 2000 h-1under the pressure of 20 ATM, to a temperature of 350oC. At this temperature they can withstand respectively 3, 6, 9, 12 and 18 hours after which restore and measure their catalytic properties and specific surface value (in terms of the previous example). The results are presented in table 3.Example 4
The example illustrates the selection of the optimal pressure stage of activation. Four sample catalyst NTK-U (D) prepare and activate analogously to example 2. The temperature at the stage of aging in circulating nitrogen 300oC. Differences in activation data samples only in the values of the pressure of the circulating nitrogen at the stage of preliminary exposure and a reducing gas during subsequent treatment with hydrogen. For the Isla activated samples were tested in the reaction of hydrogenation of butyric aldehyde in the same conditions, analogous to example 2. The most effective was the samples activated at pressures of 20-80 MPa (table. 4).Example 5
The example illustrates mainly the proposed method in comparison with the known preparation of the catalyst with high activity and selectivity in the hydrogenation of mixtures of oil aldehyde with other products of propylene hydroformylation.Three samples of catalyst NTK-U (L) 20 cm3each restore queue in laboratory flow-through environment and experience on the activity in the hydrogenation of industrial design mixture dekoratsioonid carbonylic products of propylene hydroformylation. The first pattern restore method proposed in analogue, the second method prototype, and the third by the proposed method. Recovery methods shown in example 1.Testing activity for each sample of the catalyst is carried out at two pressures of 50 and 150 ATM in the following conditions: volumetric feed rate of hydrogen 1000 h-1raw materials - 1,0 h-1the temperature of 260-280oC. the Compositions of the raw materials and hydrogenates 30 day trials of each sample are given in table. 5. It can be noted that the catalysate is aleatory, restored well-known methods in both series of experiments: at pressures of 50 and 150 ATM. Especially significant, these differences were at a lower pressure (50 ATM) hydrogenation reactions. 1. The method of activation medetinskogo catalyst for hydrogenation of aldehydes and / or their mixtures with other carbonyl-containing compounds - products of propylene hydroformylation, including the treatment of the catalyst at elevated temperature and pressure circulating at a speed of 500 - 4000 h-1nitrogen and hydrogen, characterized in that the processing of circulating nitrogen are under pressure of 20 to 80 ATM, uniformly increasing temperature for 15 to 20 hours up to 300 - 350oC, at which maintain the catalyst within 6 - 12 h; then the catalyst was cooled to 170 - 180oC and nitrogen gradually replaced by hydrogen, with the initially selected pressure and velocity of the circulating gas, followed by exposure of the catalyst after complete replacement of nitrogen to hydrogen in these conditions for 15 - 18 hours2. The method according to p. 1, characterized in that the replacement of nitrogen to hydrogen are under pressure of 20 to 150 ATM.3. The method according to p. 1, characterized in that the replacement of nitrogen to hydrogen is carried out at 170 - 230o
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