Shape-selective reactions of naphthalene over zeolites Original Research Article

Naphthalene was alkylated with propylene to isopropylnaphthalene (IPN) and diisopropylnaphthalenes (DIPN) and isopropylnaphthalene was converted (disproportionation, isomerization) in the liquid phase over various aluminosilicate catalysts, i.e. H-mordenite, HY zeolite and amorphous aluminosilicate. The reactions were studied in relation to temperature over the range of 150–300°C. The mono- and di-alkylation were less β-selective over H-mordenite (HM) than over HY zeolite or over amorphous aluminosilicate. Nevertheless, in the alkylation product obtained over HM the 2,6-DIPN/2,7-DIPN ratio was as high as 1.6–1.8, indicating shape-selectivity. In the IPN conversion test the 2,6-DIPN/2,7-DIPN ratio was initially close to 1 but then rose to almost 1.5, indicating thatIPN can be disproportionated to yield naphthalene and DIPN over the HM zeolite both on external surface and inside the pores.