Abstract
Acetylation catalysts are sorbed by cellulose in acetic acid or acetic anhydride solution, and the phenomena are important in the acetate industry to the pretreatment or acetylation of cellulose. In this report, the influence of any solvent mixed in acetic acid or acetic anhydride upon HClO4 sorption, electric conductivity, or acetylation rate was studied, and their relation or mechanism was considered.
Various solvents can be separated into 2 series: I-series includes hydrocarbons and chlorhydrocarbons (cresol, nitrobenzene also), II-series those containing -0-, =CO, -CN groups. I-series solvents are indifferent to HClO4 and so have influence of dielectric constant and dilution upon the ionization and dissociation of HClO4-AcOH complex, i. e. smaller D. K. brings smaller conductivity, larger sorption, or larger acetylation rate. II-series solvents combine with HClO4 by hydrogen bonding into complex formation and decrease HClO4 sorption or acetylation rate almost independently of D. K. further than I-series.
