Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/72—Copper
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/74—Iron group metals
  • B01J23/75—Cobalt
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/74—Iron group metals
  • B01J23/755—Nickel
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/02—Impregnation, coating or precipitation
  • B01J37/03—Precipitation; Co-precipitation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
  • B01J21/06—Silicon, titanium, zirconium or hafnium; Oxides or hydroxides thereof
  • B01J21/08—Silica

Definitions

• a nickel-alumina catalyst with an amorphous structure is obtained during the precipitation.
• catalysts from common precipitation of copper, nickel and / or cobalt with silica with a metal content between about 40 and 80% by weight, based on the total weight, i.e. the shaped, dried, tempered and reduced solid show a clear activity maximum. The maximum is pronounced at around 60 to 70%, with certain fluctuations depending on the type of metal being observed.
• the subject of the invention is therefore a process for the preparation of hydrogenation catalysts which contain copper, nickel or cobalt on a silica support, which is characterized in that aqueous solutions of salts of copper, nickel and / or cobalt with alkali silicate solutions with a ratio of Me 2 0 to Sio 2 over 1 (where Me means sodium or potassium) in such amounts that the mixture has a pH of 6 to 8 and the metal content of copper, nickel and / or cobalt in the finished catalyst is about 40 to 80% by weight % and the precipitation that occurs during the mixture is obtained in the usual way, molded, dried and treated with reducing agents.
• the catalysts are manufactured according to a principle that is the same for all metals.
• a chlorine and sulfur free compound is preferred as the metal salt, e.g. Nitrate, acetate or formate.
• a preferred approximately 1 to 3 molar aqueous solution is prepared therefrom.
• alkali silicate solution can be used as the starting material for the preparation of the catalysts.
• This water glass can have different alkali oxide / Si0 2 ratios. exhibit; the molar ratio Me 2 0 / Si0 2 can for example be between 0.25 to 1.4.
• the compounds are not stoichiometrically composed, molar ratios of 1 (which corresponds to the metasilicate) are generally present.
• alkali-rich silicates can be produced, the tendency to hydrolytically cleave in aqueous solution increases with increasing alkali content, so that compounds which are stable for a relatively long time are hardly definable here.
• Si0 2 -rich silicates contain polymeric silica anions, as is known for ordinary water glass (cf. Hollemann-Wiberg, textbook of inorganic chemistry).
• the alkali hydroxide excess is understood to be the amount of alkali hydroxide by which the (arithmetical) molar ratio Me 2 0: Sio 2 is shifted into the range above 1.
• the resulting solution contains silicate ions and an excess of alkali.
• the concentration of silications is not critical.
• the alkali silicate and the metal salt solution are combined in amounts which give the desired ratio, taking into account the concentration, preferably at an elevated temperature (for example at 60 to 90 ° C.).
• a pH in the resulting mixture is -Value from 6 to 8, preferably maintained at 7.
• the amount of alkali hydroxide required for this is determined in each case in a preliminary test.
• the precipitate is washed free of alkali and nitrate and then separated from the wash water.
• the precipitation is dried under mild conditions. To either vacuum drying at 100 to 120 ° C or spray drying at 100 to 150 ° C is used.
• Spray drying supplies the dried catalyst precursor in a particle size suitable for hydrogenation in the suspension process.
• the products from both drying methods are suitable for forming into tablets or other bodies suitable for hydrogenation in a fixed bed.
• the two solutions were fed in a 1: 1 ratio to a kettle equipped with an effective stirrer.
• a temperature of 80 to 90 ° C. was maintained in the stirred tank by external heating and by preheating the solutions.
• the pH value of 7 was maintained by regulating the feed quantity of solution 1 in the mother liquor.
• the dry matter now had a pastel blue color. After subsequent temperature treatment at 300 ° C., the dry mass had a purely green color, and the X-ray analysis showed an amorphous state.
• Part of this dry matter was mechanically brought to a grain size of 60 to 100 ⁇ , which is suitable for carrying out suspension catalytic tests.
• Another part was pressed into cylindrical tablets with the main dimensions 3 x 3 mm and then annealed at 350 ° C. In this form, the catalyst precursor is suitable for investigations in a fixed bed.
• the copper concentration in the reduced state was 62% by weight. According to this general preparation procedure, further catalysts were produced, the composition of which can be seen from the following examples.
• Example 1 The powder from Example 1 prepared for suspension catalysis was heated to 120 ° C. in an indirectly heated fluidized bed in a stream of nitrogen. After adding hydrogen in an amount of 1 to 2% by volume of nitrogen, the reduction of the copper oxide content in the catalyst precursor begins. The water formed was condensed and measured. When the water separation ceased, the temperature was increased until 180 ° C. was finally reached. The calculated amount of water was calculated. Now the nitrogen flow was shut off and the fluidized bed was fed with pure hydrogen.
• the catalyst was suspended in a mixture of methyl esters of C 4 - to C a -dicarboxylic acids, so that 5% by weight of catalyst was present in the suspension. This suspension was transferred to a heated autoclave for hydrogenation. After removing the atmospheric oxygen, the hydrogenation conditions were set: 230 ° C. and 250 bar. The progress of the hydrogenation reaction was followed by the consumption of hydrogen and by the determination of the ester number on occasionally taken samples.
• the original ester mixture had an ester number of 700, after 12 hours an ester number of 60 was found in the hydrogenation mixture.
• Ni (N0 3 ) 2. 6H 2 0 nickel nitrate (Ni (N0 3 ) 2. 6H 2 0) was dissolved in water, so that a 1 molar solution was formed.
• the water glass described in Example 1 was used to prepare solution 2, in an amount such that 0.5 mol of SiO 2 was present in 1 mol of the nickel dissolved in solution 1. 112 g of potassium water glass were therefore used for 1 l of solution 1. This does not contain enough K 2 0 to bind the nitrate ions, so that KOH had to be added to the water glass, namely 1.66 mol KOH per liter of solution 1.
• the dried precipitation was annealed at 550 ° C. Part of this mass was mechanically brought to a grain size of 60 to 100 ⁇ , which is suitable for carrying out suspension catalytic tests. Another part was pressed into cylindrical tablets with a height of 3 mm and a diameter of 5 mm. In this form, the catalyst precursor is suitable for investigations in a fixed bed.
• Example 12 prepared for suspension catalysis was gradually heated up to 570 ° C. in an indirectly heated fluidized bed with circulated hydrogen and thereby reduced.
• the catalyst was slurried in a technical, crude butynediol solution, so that a suspension with 5% by weight of catalyst was formed.
• the crude butynediol solution had the following composition according to gas chromatographic analysis:
• the catalyst suspension was transferred to a high pressure bubble column.
• the suspension was gassed with hydrogen at 90 bar and 40 to 50 ° C.
• the flow rate of the hydrogen in the (thought empty) bubble acid was 2 cm / sec.
• Samples were taken from the bubble column and analyzed at intervals of 10 minutes.
• C C multiple bonds are then no longer detectable. This end of hydrogenation was reached after 45 minutes.
• the catalysts obtained from Examples 8 to 11 were reduced in particle sizes from 60 to 100 ⁇ m in the indirectly heated fluidized bed at temperatures up to a maximum of 550 ° C. in a stream of hydrogen. They were then slurried in toluene and mixed with adipic acid dinitrile in the high pressure bubble acid. The mixture then consisted of 76% by weight of toluene, 19% by weight of adiponitrile and 5% by weight of catalyst. It was then hydrogenated at 90 bar, 100 ° C., the flow rate of the hydrogen based on the (empty) bubble column was 2 cm / sec. The progress of the hydrogenation reaction, which mainly produces hexamethylenediamine, was followed by the increase in the amine number over time. The results are summarized in Table 3.
• Example 12 a catalyst with the formula composition CuO. Co0 - Si0 2 produced, which was deformed into tablets with a height of 5 mm and a diameter of 5 mm. In the reduced state, the catalyst thus contained 67% by weight of active metals.
• a thermostable pressure-resistant reactor contained 500 ml of this catalyst. Hydrogen was passed through the catalyst bed from top to bottom, in an amount corresponding to 100 NI per hour at the reactor outlet. A pressure of 200 bar and a temperature of 75 ° C. were set in the reactor. A mixture of benzonitrile and ammonia was then run in continuously in an hourly amount of 1.2 l, 2 volumes of ammonia (liquid) being used for 1 volume of benzonitrile.
• reaction mixture drawn off consisted of 98% by weight of benzylamine, 0.05% by weight of benzonitrile and less than 2% of by-products or impurities.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Catalysts (AREA)
• Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

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• 1977
  • 1977-06-14 DE DE19772726710 patent/DE2726710A1/de not_active Withdrawn
• 1978
  • 1978-06-06 EP EP78100097A patent/EP0000055B1/de not_active Expired
  • 1978-06-06 DE DE7878100097T patent/DE2861108D1/de not_active Expired
  • 1978-06-13 JP JP7043178A patent/JPS545892A/ja active Granted

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