SU392968A1 - METHOD OF GETTING ZEOLITE-CONTAINING CRACKING CATALYSTS WITH RARE-EARTH ELEMENTS - Google Patents

Description

one

The invention of Otosit to a method for producing zeolite-containing catalysts with rare earth elements (REE), used for the cracking of hydrocarbons in the refining and petrochemical industries.

A known method for producing a zeolite-containing cracking catalyst with REE is by forming hydrogel balls in a non-aqueous medium with P: following, they are syneresis stages, introducing REE cations by ion exchange, salt washing, drying and calcining.

The disadvantage of this method is the uneven distribution of REE over the volume of the catalyst ball Uipn by introducing small amounts of these elements, which causes the balls to break down during calcination.

The purpose of the invention is to reduce the consumption of REE, ensuring their uniform distribution throughout the volume of the ball and preventing the destruction of the catalyst during calcination is achieved by introducing REE into the catalyst during the hydrogel formation stage at pH 6.5-9.0.

The essence of the method is as follows. A solution of an acidic aluminum salt is fed into the jet mixer, in which the required amount of REE salts and sodium silicate solution containing zeolite crystals in sodium form are preliminarily introduced.

By mixing these components, a rapidly coagulating sol forms in streams in a layer of hydrocarbon liquid. The streams are broken into pa droplets, which then coagulate into hydrogel hydrogel. During jet mixing, there is a uniform distribution of REE in the resulting ash, and then in the hydrogel beads. The hydrogel beads are subjected to syneresis under conditions that ensure the formation of the necessary porous structure of the finished catalyst, then the exchange of sodium ions to ammonium ions is carried out in order to ensure the necessary catalytic and mechanical properties of the catalyst. After

This hydrogel ball washed from salts, dried and calcined in a vapor-gas atmosphere.

The proposed method was tested on a pilot plant and gave positive results.

When M Q p. Solutions of liquid glass (1.7 n., Silicate module 2.74) and aluminum sulphate (1.2 n.) Containing 68 g / l H2SO4 and 9.1 g / l REE compounds (in terms of oxides) are mixed in a jet mixer with an aqueous suspension of zeolite NaX (98 g / l) in an amount to ensure the content of zeolite in the finished catalyst is 16 weight. % Formed quickly coagulating

the sol is fed to the grooved cone obtained

the streams enter the oil and break into droplets, chilling the hydrogel into globules. pH ash 7.0, flow rate 1.8 l / min. Balls gel subjected to syneresis at 60 ° C for 12 hours and ion exchange with a solution of ammonium nitrate (16 g / l) at 50 ° C for 40 hours. Then the hydrogel balls are washed with distilled water from salts, dried at 130–140 ° C, and calcined in a stream of water vapor at 750 ° C for 12 hours. In tab. 1 compared the physico-chemical properties of the catalysts obtained by the known and proposed methods, and in table. 2 - catalytic properties of catalysts treated with 40% and 100% steam.

Table 1

table 2

Cracking the sulfurous distillate

Output weight%:

fractions with NK 195 ° С of coke gas fraction 195-350 ° С

The degree of transformation, selectivity,%

Subject invention

A method for producing zeolite-containing cracking catalysts with rare-earth elements by forming hydrogel balls in a non-aqueous medium with subsequent syneresis stages, ion exchange with ammonium salt solutions, washing from salts.

drying and calcination, characterized in that, in order to reduce the consumption of rare earth elements, ensure their uniform distribution over the catalyst granule and prevent catalyst destruction during calcination, rare earth elements are introduced into the catalyst during the formation stage

hydrogel at pH 6.5-9.0.