| From the isobutane alkylation with butene at the presence of acidic catalyst, alkylate is the ideal blend component of automobile gasoline. The alkylate processes use H2SO4 and HF as catalysts, but the disposition of spent H2SO4 and the volatilization of HF bring serious environmental concern, it is significant to develop environmentally friendly solid acid catalyst for the reform of traditional catalystWe select the catalytic system as follows: WO3/ZrO2; Zr(SO4)2 supported on Al2O3 or SiO2; MxOy/H β molecular sieve, the catalytic behavior of the catalysts above mentioned were systematically investigated. The results revealed that the addition of WO3 plays on an important role to stabilize tetragonal phase of ZrO2. Tungsten dispersed on the surface of zirconium oxide greatly were in monolayer, and the deposited crystalline of WO3 can partly interacted with ZrO2, Zr-O-W, the chemical bond having strong acid effect. Compared with others solid acid, the catalyst of WO3/ZrO2 has better initial activity and the selectivity of i-C80.Compared with WO3/ZrO2 solid acid catalysts, the M-WO3/ZrO2 promoted with transition metal have varied their crystal structure, surface state and acid amount. Based on the reaction mechanism, it was elucidated that the addition of transition metal had scarcely and effect on the catalytic performance.The WO3/ZrO2 carried with superfine ZrO2 solid acid catalysts have a larger specific area, acidic amounts and loading capacity of metal oxide, it has better reactive activity, The selectivity decreases due to more cracking products of C5C7.A series of strong solid acid catalysts of Zr(SO4)2 calcined at different temperature and Zr(SO4)2/Al2O3(SiO2) with various loadings were prepared. The variations of crystal structure, specific surface area, surface acid quantity and acidic strength with the loadings and calcinationed temperature were elucidated. Different properties were observed when Zr(SO4)2 loaded on aluminum or silica. Especially on aluminum, the decomposition of Zr(SO4)2 and crystal phase transfer of zirconia were etarded, and the acid amount, strength and react activity were increased. All of the samples have a rather good selectivity.The basic character of MxOy/H P (Li, Ca, La---)and H ￡ samples are similar, however, the catalytic activity and acidic properties have changed. The sample loading on the Tm2O3/H P has better stability, and the proportion of alkylate is increased.
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