from first principles PP-I-1

PP-III-40Regularities of Formation of Hydrocarbon Cracking Catalystsfor Modification of Natural Zeolite by Acids of Various NatureKadirbekov K.A., Konuspaev S.R., Nurbaeva R.K., Zhambakin D.K.JSC "Institute of Chemical Sciences. AB Bekturov ", Almaty, Kazakhstankkairati@mail.ruThe report examines the scientific basis of the creation of hydrocarbon cracking catalysts inthe synthesis of long chain α-olefins. It is known that the cracking of hydrocarbons runs onacidic centers, therefore ideal catalysts for this process are solid acids. Zeolites as solid acidsare the main catalysts for hydrocarbon cracking processes.We established that stepwise modification of natural zeolite by mineral, organic andheteropolyacids leads to an increase in its catalytic activity. The regularities of formation ofcracking catalysts modified by acids were identified by modern physical methods (XPS,SEM, TEM, BET). It is shown that as a result of active interaction of the surface withmodifier new structures are formed, which leads to a significant increase in specific surfacearea and catalytic activity. Thus, when stepwise modification by mineral acid at first and thenby heteropolyacids, dispersibility of the particles of heteropolyacids on the surface of naturalzeolite is high, and the layered structure of the zeolite are covered with agglomerates ofheteropolyacid evenly distributed and firmly bounded to its surface. Detailed study of thesurface of the zeolite by HQ TEM showed the formation of stable structures of clusters, whichare partially embedded in the volume of the zeolite. The size of these clusters is 1-2 nm andthey are available for the reactants. It is believed that when applied and as a result ofcalcination of the catalyst, transfer of the particles of heteropolyacids in highly dispersed statein which the heteropolyacid particles reach specific adsorption and catalytic properties areachieved.Obviously, the formation of nanostructures and the presence of the large number of strongacid sites lead to increase in cracking activity of catalysts in the cracking of heavyhydrocarbons. [1,2]References:[1] S.R.Konuspayev. K.A.Kadirbekov, R.K.Nurbayeva, and A.T.Sarsekova New Catalysts Based onthe Heteropoly Acid–Zeolite System for the Synthesis of Higher α-Olefins by Paraffin Cracking //Catalysis in Industry (2011) Vol. 3, No. 1, pp. 76–80.[2] S.R. Konuspayev, K.A. Kadirbekov, A.T. Sarsekova, D.R. Nurbayeva, D.K. Zhambakin, Catalyticsynthesis of higher α-olefins by paraffin cracking, Petroleum Chemistry, 2010, Vol. 50, N. 5, 368-372192