Kinetics of the vapor‐phase oxidation of napthalene over a vanadium catalyst

Rates of oxidation of naphthalene were measured for the temperature range 300°C. to 335°C. using a thin layer of vanadium oxide‐potassium sulfate‐silica catalyst in a flow reactor. The amounts of naphthalene converted were determined by analysing the products for 1,4‐naphthoquinone, 1,2‐naphtho‐quinone, and phthalic anhydride. Negligible amounts of products of complete combustion were formed. The reaction rate data obtained at low conversions of naphthalene were correlated by the following expression, based upon a model for the reaction proposed by Hinshelwood:\documentclass{article}\pagestyle{empty}\begin{document}$$ r_n = \frac{{k_a k_n C_n C_o}} {{k_a C_o + Nk_n C_n}} $$\end{document}From the results of experiments in which the contact time was varied, it was suggested that the reaction course consisted of two parallel, consecutive reactions in which 1,4‐ and 1,2‐naphthoquinone are intermediates in the formation of phthalic anhydride.