CS272631B1 - Method of dehydrogenation catalyst's copper coating - Google Patents

Abstract

The subject of the solution consists in the method of copper coating of catalyser zinc on iron and in good quality of copper layer on the catalyser surface. The above mentioned purpose is achieved by regulation of the copper coating by development of coppering operations in time.<IMAGE>

Description

(54)

Method for reducing the dehydrogenation catalyst

The purpose of the sputtering is the epoxy process of the zinc catalyst on iron and the good quality of the copper layer on the catalyst surface. This is accomplished by the fact that the a?

CS 272631 Bl

CS 272631 Bl

The present invention solves an epoeobic dipping of a dehydrogenation catalyst.

The intermediate of caprolactase production cyclohexanone and produced worldwide mainly by oxidation of cyclohexane, then by dehydrogenation of phenol. In both cases it is necessary to dehydrogenate cyclohexanol to cyclohexanone,

The cyclohexanol dehydrogenation process is carried out catalytically at a temperature of 550 K to 750 K.

^C 6 ^H 11 ^{0H C} 6 ^H 10 ° * ^H 2 and ^h " ^{65 k0 // mo1}

The reaction is endothermic - it takes place in a tubular reactor, the heat being most often supplied by combustion gases from natural gas combustion or hydrogen combustion from the process itself ·

The addition of water (RO 79 492, DE 2 347 097) retardes by dehydrogenation of cyclohexanol to cyclohaxene, but may present energy disadvantages. The addition of oxygen (PL 136 018) allows the process to be carried out adiabstically / but with high safety requirements.

The economics of the process of dehydrogenating cyclohexanol to cyclohexanone is largely determined by the catalyst used. In terms of composition, a variety of catalysts, both grained and industrially utilized, are known.

On the basis of foaphides, the nickel catalyst most commonly promoted by eodicorum (SU 716 583) in the form of hydroxide is known, and the cobalt catalyst is most often used in the form deposited on a natural carrier, so-called. knit turf (SU 697 177, SU 856 939). Also known are the magnesium catalyst (Emeljanov NP: DAN BSSR 12 1968/10 / 914-7) and the palladium-retenium membrane catalyst (Basov NL ·· .: -Sov. - fd. Seminar after ketalization, Sb. Dokl. Moscow 1983) / 34-7).

The zinc catalyst can be deposited on carbon (SU 249 354), - in the form of zinc oxide (RO 66 847) / in a chromium alloy (Glozmann S, S. ····: Tr. Vesa. Nuč, Iesled. Why ·, Xnat.-Monomerov (1969, 1, 82-9) / Zakrevsky VK ·· .: Chim. prom. et. Moscow 1980, 9, 527-8) or in the form of zinc chromene (SU 348 540, RO 79 942).

Classically mentioned copper catalyst for the title process requires low temperatures with little conversion required for conversion (Orizarsky 1,: Geterogenyje Catalysts Trudy Međunarodnogo Simpozia 3 rd, 1975, publ. -BAN Sofia, Vladee R. ·, ·> Rav Chim, 30 (1980/8 / 759-62),

For this reason, it is necessary to use the sword as an alloy in the form of alloys or supported on it. Catalysts in combination with manganese (SU 697 179, SU 979 324) / and magnesium (SU 411 888 / Zrblova 1.0.) Are known. Moscow 1979/12, 713 14) 8 Calcium (Kozlov NS- ··. ·: Vesci AN USSR, Ser. chim, navuk 1978, 5, 84-6). The copper catalyst in combination with aluminum is either in the form of an alloy (Petrova V. ... Chim. Ing. Sofia 1983/9, 401-3) or in the form coated on alumina (SU 522 853). In combination with a pot, it is promoted by potassium oxide (Belskaya RI, ···: Vasci AN BSSR, Ser. Chim. Navuk 1975/2 / 97-102) or in a silica gel coated form (Kocurkova L. ....: Chem. Prum. 30 1980, 2 / 71-4). On the carbon the sword is deposited with palladium (Red L. ....: Chem, pr. 29 1979, 3, 127-8) or is it me? applied to the so-called. shungite / which is a natural mixture of oxides (SU 910 178). Catalyst oxide as the catalyst is most commonly used in combination of 8 chromium oxide (3P 83 157 741) promoted by barium oxide (FR 1 513 220) or barium oxide and graphite (SU 574 433). Maff in combination with chromium and fever also appears to be a good catalyst (Belakaja R.Io. · «·: Vesci AN BSSR / Ser, chim. Navuk 1977, 4, 41-5), possibly with cobalt (3P 80 136241) / β cobalt-based cobalt (SU 891 145) / or β cobalt-coated cobalt. turf felt (SU 936 989) ₀

The most widely reported and probably used are catalysts of meJ on zinc oxide (CS 151 166 / Emeljanov NPt DAN BSSR II 1967, 3, 233-6), whereby the sword can be applied in the form of oxalate (FR 2 030 602 / US 3,652,460) and by subsequent oxidation of the hydrogenation of the catalyst in three cycles. Modified can be 2: 1 (SU 978 909) using barium oxide and routine, optionally with sodium carbonate (GB 1 060 484). The catalyst of the medium and zinc can be modified with chromium (Bear's ON, Pr, -vo organ, products, 'Moscow 1982, 15-22) or calcium, barium and etronium (Baxskaya R, I,

Veeci AN BSSR / Ser, chim navuk 1981, 5, 112-6),

Known is the BASF catalyst H 5-10 chemical composition zinc oxide promoter activated Oe in the form of extruders with a diameter of 4 mm or 6 mm. It is characterized by a bulk density of approximately 1 550 kg / a and a mechanical strength of more than 10 kg,

A lower bulk density of approximately 1400 kg / m &lt; ^{2 &gt;} is characterized by a catalyst prepared from a galvanized low-ferrous iron sheet by shearing and forming into the form of non-closed tubes of approximately 7 mm x 7 mm x 0.5 mm. The zinc content of the catalyst is about 7% by weight. The average conversion of cyclohexanol at about 673 K is approximately 75%. Increasing the temperature in the reaction makes it possible to increase the conversion but proportionally decreases the selectivity of the reaction and consequently increases the raw material costs and complicates the process of cyclohexanone purification. . It is also desirable to have a catalyst regeneration time consisting of firing the so-called polymer to charred pitch with air.

This catalyst is improved (PL 102 493) by the application of medium in an amount of 0.001 to 0.5 kg per square meter of catalyst surface. The effervescence is carried out by immersing the catalyst in a solution of raffinate or ammonium salt or pouring the solution. K Is approximately 80%,

SUMMARY OF THE INVENTION The present invention is directed to a method of zinc-iron plating of a dehydrogenation catalyst by chemical precipitation of a medium from a solution of its inorganic aols at a concentration ranging from 0.02 mole per liter to 2 moles per liter in the presence of ammonia. It is characterized in that the agitated catalyst particles are treated with ammonia water in the first seventh time and in the remaining six sevenths of the time of ammoniacal water and m.p.

The advantage of the coating according to this process is the slow formation of a layer of media, which makes it uniform and firmly attached.

Example

75 kg of a galvanized, low-carbon iron sheet prepared by shearing and molding into open tubes having an approximate size (? 7 mm x 7 m x 0.5 mm with a zinc content of approximately 7% by weight) are pre-charged with a coater. 45 kg of β is added and 2/8 kg of ammonia water with an ammonia concentration of approximately 25% by weight, 1 kg of meffnatate sulphate (CuSO 4 x 5 HgO) is added after stirring for 1 minute. The catalyst used is characterized by a 99% selectivity in the cyclohexanol dehydrogenation reaction, a natural gas consumption of 27.46 m ² per tonne of cyclohexanone produced, and the catalyst is dried at a temperature above 50 ° C. · With a service life of 1.5 years and at least a monthly duty cycle.

Claims (1)

PREOMET OF THE INVENTION Method of coefficient of zinc-on-iron dehydrogenation catalyst by chemical exclusion of media from solutions of inorganic salts with a concentration ranging from 0.02 mol per liter to 2 mol per liter in the presence of ammonia with a molar ratio of ammonia to CS.272631 Services of 0, 2 to 20, characterized in that the unmixed catalyst particles are treated with ammonia water in the first seventh of the treatment period and the remaining six sevenths of the soaking time with ammonia water and copper aol added to the ammonia water in crystalline form in the second seventh time of pomsffing ·