Abstract—The dealuminated H-Mordenite (MOR) was used as a molecular reactor for the selective formation of the least bulky 4,4’-diisopropylbiphenyl (4,4’-DIPB) in the isopropylation of biphenyl (BP). The selective formation of 4,4’-DIPB through 4-isopropylbiphenyl (4-IPBP) was observed due to the differentiation from the other bulky isomers by the MOR channels. 4,4’-DIPB selectively allowed the transition state of 4-IPBP by their steric restriction of the channels. The selectivity for 4,4’-DIPB decreased at high temperatures and/or when a large amount of the catalyst was used. These are due to the isomerization of 4,4’-DIPB, once formed in the channels, to a thermodynamically stable 3,4’- and 3,3’-DIPB at the external acid sites. Y-zeolite (FAU) and zeolite-β (BEA) possess wide channels to accommodate the bulkier isomers, which allow the transition states of IPBPs to the DIPBs with 2- and 3-isopropyl moieties.
Index Terms—Biphenyl, isopropylation, molecular reactor, mordenite, shape-selective catalysis.
The authors are with Future Industries Institute, University of South Australia, Mawson Lakes, 5095 SA, Australia (e-mail: stalinjoseph143@gmail.com, sugiyoshihiro@gmail.com, kavitha.ramadass@gmail.com, baskaranrajesh@gmail.com, vinu.ajayan@gmail.com).
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Cite: Stalin Joseph, Yoshihiro Sugi, Kavitha Ramadass, Baskaran Rajesh, and Ajayan Vinu, "H-Mordenite as a Molecular Reactor for the Isopropylation of Biphenyl," International Journal of Chemical Engineering and Applications vol. 9, no. 2, pp. 76-81, 2018.
