| Popis: |
Recently, the large pore MCM-41 material has gained a considerable amount of interest, as a solution to the diffusion limitation provided by the conventional microporous cracking catalysts for the cracking of long-chain or bulky hydrocarbon feeds. The present work deals with the synthesis and characterization of novel mixed Al-MCM-41/MFI catalyst systems. Furthermore, the catalytic behavior of the as-synthesized Al-MCM-41/MFI mixed systems for cracking hydrocarbons by MAT (Micro Activity Test), standardized by ASTM D-3907, have been investigated in the present work. In situ formation of the meso- and microporous structures Al-MCM-41 and ZSM-5 have been obtained using a two-template [C16H33(CH3)(3)NBr and (CH3CH2CH2)(4)NBr] synthesis gel system. The mixed phases were obtained by optimizing template ratios and reaction temperature. The comparison with conventional zeolite Y and pure MCM-41 with regard to activity and selectivity showed a better activity and selectivity towards C-3 and C-4 fractions. The obtained results reveal a potential of mixed Al-MCM-41/ZSM-5 catalyst systems as cracking catalysts and, in turn, demand further optimization of physicochemical properties in the future in order to be exploited as commercial cracking catalysts. |
