| During the process of polyvinyl alcohol production, a great deal of methyl acetate is produced as by-product. In industry, methyl acetate is hydrolyzed into acetic acid and methanol for recycle using. Therefore, the effective hydrolysis of methyl acetate is very significant. In order to accelerate the hydrolysis of methyl acetate, modification of acidic cationic exchange resin catalyst and micellar catalysis were studied in this paper. In addition, the kinetics of the hydrolysis of methyl acetate deduced by pseudohomogeneous and heterogeneous models were reported. The following presents the main results in detail.The solid acid catalysts which consisted of Lewis acid and heteropoly acid(HPW) supported on cationic exchange resin(NKC-9) were prepared by impregnation technique. The properties of the catalysts were characterized by IR, UV-Vis, XRD, and the catalysis activity was evaluated by the hydrolysis of methyl acetate using a batch stirring-type reactor. The experiments showed that the superacid catalysts modified with lewis acid were not obtained at our experiment conditions; The supported heteropoly acid catalyst prepared by dipping NKC-9 into 15%(wt)HPW solution at 50℃had a HPW loading of 63.6%(wt) and the conversion of methyl acetate catalyzed by it had an enhancement of 7% in 1hour, however, HPW with high loading lost easily.The acidic hydrolysis of methyl acetate in micellar solutions of surfactants (SDBS, NaLS, TX-100, CTAB and mixed micellar systems) and the influence of temperature and NaCl on the hydrolysis of methyl acetate in presence of NaLS was investigated. The results indicated that the hydrolysis was inhibited by anionic SDBS; promoted by anionic NaLS and CTAB; Nonionic TX-100 had no effect on the hydrolysis. When the concentration of NaLS was 0.121mol/L, the conversion of methyl acetate was increased 10% in 1hour and the reaction almost reached equilibrium in 2.5hours. The action of mixed micellar systems was...
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