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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Reaction of meta-diisopropylbenzene on acid molecular sieves and synthesis of zeolites by a vapor phase transport method

Kim, Man-Hoe 20 October 2005 (has links)
Meta-diisopropylbenzene is reacted with propylene over the acid form of the molecular sieves SAPO-5, mordenite, offretite, beta, hexagonal and cubic faujasite (hex and FAU), L, SAPO-37, and an amorphous silica-alumina at temperatures around 463 K in a flow-type fixed-bed reactor. A small amount of cracking is observed. The main reactions of meta-diisopropylbenzene are isomerization and alkylation. This alkylation is proposed as a new test reaction to characterize the effective size of the voids in larger pore (12 T-atom rings or above) molecular sieves by measuring the amount ratio of formed 1,3,5- to 1,2,4-triisopropylbenzene. In most cases, this ratio increases with the increasing effective void size of the molecular sieves in the order: SAPO-5 < mordenite < offretite < beta < hex ≈ FAU < L < SAPO-37 < amorphous silica-alumina. Since samples with the FAU topology show lower selectivities to 1,3,5-triisopropylbenzene than the mesoporous, amorphous silica-alumina, pore curvature has an influence on alkylation selectivity even for voids of 13 A size. / Ph. D.

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