PL163601B1 - Method of obtaining a catalyst in the form of microspheres for use in cracking processes - Google Patents

Abstract

A method of producing a microspherolide catalyst for a cracking process by mixing zeolite, aluminum oxide and / or hydroxide with a binder obtained by hydrolysis of the silicate ethyl-40, characterized in that the zeolites of the fotosite type are in hydrogen form and / or modified rare earth elements and / or zeolite type ZSM-5 and aluminum hydroxide are mixed with a polyethoxysiloxane binder obtained by hydrolysis at 30-T9 ° C aqueous-alcoholic solutions of ethyl silicate-40 in the presence of acids in a silicate ratio ethyl / water above T, I4 and ethyl silicate / ethyl alcohol above I, I6; and received the mixture is dispersed in an aqueous solution with a pH above T.

Description

The present invention relates to a method of producing an aluminosilicate catalyst for cracking processes in the form of microspheres with a diameter of 20 - 160 µm.

Until now, aluminosilicate catalysts have been obtained by co-precipitation and ball forming in an oil column. Catalyst spheres having dimensions from 2-6 mm after drying and calcination are obtained by this method. These grains are then ground to a size suitable for the fluidization process (40-150 μιη). The obtained non-spherical aluminosilicate is additionally ion exchanged in order to increase the catalytic activity. Due to their irregular shapes, these catalysts do not have the high abrasion resistance necessary in fluidization processes.

Microsteroid catalysts are also obtained by spraying. One method is to prepare a complex sol which includes a water glass solution and an aluminum salt solution. The obtained sol is sprayed onto the oil column where the sol droplets coagulate onto the gel. This method also requires ion exchange activation and is cumbersome due to the need to wash the balls from oil, which requires apparatus with special design solutions.

Another spraying method consists in preparing a mixture of gels by co-precipitating from a solution of water glass and an aqueous solution of aluminum salts, or preparing a mixture of gels by precipitating aluminum hydroxide on previously precipitated silica gel, or preparing a mixture of gels by saturating the silica gel with aluminum salts, which during roasting they convert to Al2O3, and then spray-dry the prepared gel.

According to Polish patent description No. 61,084, an aluminosilicate catalyst is obtained by mixing and homogenizing previously precipitated gels of silicic acid and aluminum hydroxide. Gels washing of SO 4 ^2- ions and NO3 ^_ mixed at any ratio selected, usually so that the final product Al2O3 content was 10-25% by weight. After homogenization, the mixture is spray-dried.

Known methods of producing zeolite microspheroidal catalyst for the cracking process consist in producing an amorphous aluminosilicate matrix and introducing a modified Y-type zeolite into it. The matrix is obtained by a known method consisting in, for example, production of silica gel by carbonization of water glass, maturation of this gel, adding a carbonate solution with sodium, re-aging the mixture, and then adding the aluminum sulphate solution. The mixture of zeolite and aluminosilicate matrix is spray dried and the obtained grain is ion exchanged.

The aim of the present invention was to eliminate the spray-drying step from the cracking catalyst production process and the onerous preparation of an aluminosilicate matrix with a pore diameter above 10 nm and to increase the mechanical resistance to abrasion of the finished catalyst.

Unexpectedly, it turned out that using ethyl silicate - 40 after its hydrolysis at 30-79 ° C in an acidic environment while maintaining the ratio of ethyl silicate / water above 7.14 and ethyl silicate / alcohol above 1.16, aluminum hydroxide and zeolites of the type After homogenization, the photoite in the hydrogen form and / or modified with rare earth elements and / or the zeolite of the ZSM-5 type can be dispersed in an aqueous solution with a pH above 7, preferably in an ammonia solution, obtaining microspheroidal catalyst grains with high mechanical resistance to abrasion and dimensions below 200 µm . The obtained catalysts in the cumene test consisting in dosing cumene to the reactor at a temperature of 500 ° C with a load of 1 h, showed 100% conversion.

The main advantage of the method according to the invention is the possibility of obtaining microspheroidal catalyst grains by dispersing a zeolite suspension in an aqueous environment, the method does not require complicated equipment, and the aluminosilicate matrix ensures high mechanical resistance to abrasion and, thanks to high porosity, ensures fast transport of raw material and products from the catalyst grain, which is important for high volume flow rates of the raw material used in cracking processes.

Example I.

1000 cm ^J of ethyl silicate - 40 was mixed with 430 cm J of ethanol and 70 cm of distilled water. After mixing, 1 cm ³ of nitric acid was added. With constant stirring, the mixture was heated to 60 ° C for 2 hours. After cooling, the solution was left for 24 hours.

300 cm3 of the solution prepared as above were mixed with 30 g of Al (OH) 3 and 10 g of NaY zeolite. The hardened catalyst grains were left in the solution for 2 hours, then washed with 1 liter of distilled water, and dried for 2 hours. at 120 ° C and calcined 4 hours. at 500 ° C. The cracking catalyst was obtained with the composition: SiO2 - 72.0%; Al2O3 - 21.95%; Na ₂ O - 0.6%; Fe2O3 0.13%; part dissolution in H2O-1.5% with mechanical resistance to abrasion above 96% and grain size from 40 - 200 μm. 100% conversion was obtained in the cumene test at 500 ° C.

Example II.

300 cm3 of the solution prepared as in Example 1 was mixed with 30 g of Al (OH) 3 and 10 g of NH4LaY zeolite. After hardening, the catalyst grains were left in the mother liquor for 2 hours, decanted the solution, washed with 1 dm ³ of distilled water and dried at 120 ° C for 2 hours. and calcined 4 hours. at 500 ° C. The cracking catalyst was obtained, grain size 40-200 µm, mechanical resistance to abrasion 97%. 100% conversion was obtained in the cumene test at 500 ° C.

Example III.

300 cm ³ prepared as in example 1 was mixed with 30 g Al (OH) 3, 5 g NH ₄ LaY and 5 g HZSM-5, after homogenization, the mixture was poured into 2 dm ³ of distilled water, alkalized 40 cm ^{3 with} 25% NH3 aq, with intensive stirring . Spherical-shaped catalyst grains harden after 2 minutes. mixing. The catalyst was left for 2 hours. in the mother liquor, the solution was decanted, and the catalyst was washed with distilled water, dried and calcined as in Example 2. The cracking catalyst was obtained with particle size lower than 200 µm, mechanical resistance to abrasion 95%. In the cumene test, the conversion was 100% at 500 ° C.

Publishing Department of the UP RP. Circulation of 90 copies. Price: PLN 10,000

Claims (2)

Patent claims A method for producing a microspherolide catalyst for a cracking process by mixing zeolite, aluminum oxide and / or hydroxide with a binder obtained by hydrolysis of 40-ethyl silicate, characterized in that zeolites of the fojazyt type in hydrogen form and / or modified with rare earth elements and / or zeolite of the ZSM-5 type and aluminum hydroxide are mixed with a polyethoxysiloxane binder obtained by hydrolysis at 30-79 ° C of ethyl silicate-40 water-alcohol solutions in the presence of acids with an ethyl silicate / water ratio above 7.14 and ethyl silicate / ethyl alcohol above 1 , 16; and the obtained mixture is dispersed in an aqueous solution having a pH above 7. 2. The method according to p. The process of claim 1, wherein the dispersion is in an aqueous ammonia solution.