Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9623704 | Chemical Engineering Journal | 2005 | 7 Pages |
Abstract
The industrially important cymene synthesis was carried out by toluene isopropylation over cerium-exchanged NaX zeolite. The modification of NaX zeolite by cerium exchange was found to enhance the catalytic activity of the zeolite to a considerable extent. The reactions were carried out in a fixed-bed flow reactor at atmospheric pressure with nitrogen as the carrier gas. The reaction conditions were optimized by varying temperature, reactants mole ratio and space-time. It was observed that in the isopropylation of toluene, the isopropyltoluene fraction contained both para and meta isomers. There was no ortho-cymene in the product stream. Alkylation studies at 433-513Â K showed a decrease in p-cymene selectivity with increase in reaction temperature and increased formation of diisopropyl toluene at lower temperature. A systematic and detailed kinetic study was carried out for the alkylation reaction. From the product distribution pattern, a kinetic model for the reactions was proposed by following Langmuir-Hinshelwood approach. The kinetic and adsorption parameters of the rate equation were determined by non-linear regression analysis. The apparent activation energy for the main reaction was found to be 48.12Â kJ/mol.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Chemical Engineering (General)
Authors
Sanghamitra Barman, Sunil K. Maity, Narayan C. Pradhan,