SHAPE-SELECTIVE ALKYLATION OF NAPHTHALENE WITH ISOPROPANOL OVER MORDENITE CATALYSTS

Naphthalene alkylation with isopropanol was studied at 250-degrees-C using several proton-form mordenites (HM) and Y-zeolites. HM catalysts afforded 2-isopropylnaphthalene (2-IPN) as the dominant product, whereas the Y-zeolites (HY and LaHY) gave 1-IPN as a major product. HM displayed better selectivity to 2-IPN and 2,6-diisopropylnaphthalene (2,6-DIPN), although HY showed higher activity for naphthalene conversion. HM catalysts with SiO2/Al2O3 ratios of 20-35 appear to be effective for shape-selective synthesis of 2-IPN and 2,6-DIPN. These catalysts displayed over 73% beta-selectivity to 2-IPN among the two IPN isomers, and over 65% beta,beta'-selectivity to the desired 2,6-DIPN among all DIPN isomers with 2,6-DIPN/2,7-DIPN ratios of about 3. The isopropanol-to-naphthalene ratios and the solvent type are also influential for both activity and selectivity of mordenite catalysts.