Catalytic Activity of Al₂O₃ Treated with CF₃Cl for Vapor-phase Reactions of Benzene with Compounds Containing CF₃ Group

Abstract

Alumina treated with CF₃Cl promoted the vapor-phase alkylation of benzene with CF₃ CH-CH₂ The reaction was carried out by using a continuous flow reactor under an atm ospheric pressure at 100∼450°C. The maximal catalytic activity was obtained when Al₂O₃ was treated with CF₃Cl at about 420°C (Fig.3). The alumina surface was partially fluorinated by the treatment with CF₃Cl, nevertheless the amorphous structure of alumina was almost maintained during the treatment (Fig.1). The formation of fairly strong acid sites was ascertained by the adsorption of NH₃ at a high temperature (420°C) (Table 5). This site was considered to be of Brønsted type. The CF₃Cl-treated Al₂O₃ also promoted the reactions of benzene with CF₃COCF₃, CF₃CHO, and other CF₃ -containing compounds (Fig.5 and Table 7).