The Catalytic Dehydrogenation, Dehydroxylation, and Dehydroxymethylation of Benzyl Alcohol. II. The Effects of Sodium Compounds as Additives

Abstract

Abstract The reaction of benzyl alcohol has been examined over stabilized nickel (S-Ni) catalysts which have been modified by treating the catalyst surface with solutions of sodium compounds; this has been done in order to obtain some information about the relation between the behavior of the molecule adsorbed on the metal catalyst and the chemical nature of the catalyst surface. On the basis of the fH, fCH3, and fCHO values, which were defined as representing the catalytic activity for the formation of benzene, toluene, and benzaldehyde respectively, the variation in the activity for each modified S-Ni was evaluated. The general aspects may be summarized as follows: (1) The reaction is generally retarded with an increase in the amount of a sodium compound which is adsorbed on the catalyst during the modification process. (2) When the modification is of a lower grade, the effect of additives on the catalytic activity represented by f values is in the following order: NaNO3<NaOH<Na2S2O3<NaI<NaBr<NaCl. (3) A proper amount of NaCl on the catalyst promotes the reaction. The increase in SH and SCH3 values, which were defined as representing the selectivity factors for the formation of benzene and toluene toward that of benzaldehyde, is roughly associated with the increase in the corresponding f values.