Optimizing the Catalytic Transfer Hydrogenation of Naphthalene to Tetralin via Response Surface Methodology

Transfer hydrogenation of naphthalene is a safe and effective method to produce tetralin. Partial transfer hydrogenation of naphthalene was performed at a constant pressure of 7 bar in the presence of 2-propanol (as hydrogen donor) and the Raney nickel catalyst. Raney nickel to naphthalene mole ratio, 2-propanol to naphthalene stoichiometry ratio or Φ, and time were the main and effective parameters. Response surface methodology was used to optimize the parameters. A quadratic correlation was proposed for the tetralin conversion is 0.3 to 0.7 for Raney nickel to naphthalene mole ratio, 3 to 6 for Φ, and 0.5 to 3 hours for reaction time. The optimum values for Raney nickel to naphthalene mole ratio, Φ, and time were 0.6, 4.5, and 1.75 h, respectively. Under these conditions, the conversion value was obtained as 99.6 % which was satisfied with experimental data. Results showed that the Raney nickel to naphthalene mole ratio had the most effect on the conversion whereas Φ had the least effect.