INFLUENCE OF MODIFICATION OF KAOLINITES BY ALUMINUM OXIDE ON THE CRACKING ACTIVITY OF PETROLEUM RESIDUE

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The preparation of matrices of zeolite-containing catalysts using acid-treated (20% H2SO4) kaolinites from the Pavlodar region of Kazakhstan (NPK-1, NPK-2 and NPK-3) with subsequent modification with aluminum hydroxo complexes of different concentrations (2.5, 5.0 and 7.5 mmol Al3+/g) was studied. and aluminum hydroxide gel prepared by the ammonia method for activity in cracking residual petroleum feedstock. In the experimental part of the article for kaolinites of the Pavlodar region of Kazakhstan - PK-1, PK-2 and PK-3, the values of the SiO2/Al2O3 molar ratios in the original samples, the change in these ratios during acid activation and subsequent modification with aluminum hydroxo complexes are considered. It has been shown that the criterion for choosing kaolinites as matrices for zeolite catalysts can be the increased content of aluminum oxide in the original kaolinite. From the analysis of data on the matrix activity of kaolinites in the cracking of vacuum gas oil, it follows that in order to achieve optimal yields of gasoline and light gas oil for samples with lower Al2O3 content, the introduction of a higher concentration of hydroxo complex is required. Using the example of the Al(2.5)NPK-1 sample, it is shown that the additional introduction of aluminum hydroxide gel (5% Al2O3 by weight of the catalyst) obtained by the ammonia method into the modified kaolinite matrix, followed by drying and heat treatment leads to the production of a catalyst with high activity. The catalyst was tested in the cracking of fuel oil, a mixture of vacuum gas oil (VG) with fuel oil (30%). For comparison, data on cracking of heavy vacuum gas oil are presented. Gasoline yields for these types of raw materials at 5000C are 26.8; 31.9 and 39.1%; respectively, with raw material conversion of 88.4% and 92.1%. Cracking gasolines are characterized by a high content of iso-paraffin and aromatic hydrocarbons. Al(2.5)NPK-1+Al2O3 can be an economically beneficial and environmentally friendly catalyst and adsorbent.