| Popis: |
Departmcnt of Chemistry, Faculty of Science, Al-Azhar University, Cairo, Egypt Department of Chemistry, Faculty of Science, Cairo University, Giza, Egypt Manuscript received 25 June 1991, accepted 29 July 1993 Kinetics of the reaction between a newly synthesised sulphonated cation exchange resin and ethyl formate solution have been studied in dioxane-water mixtures of varying compositions of dioxane (0-45%, v/v) at different temperatures (20-40°). The order of the reaction in the heterogeneous catalysis by the resin was found to be the same as in the homogeneous catalysis by a dissolved electrolyte. The rate constant increased with the increase in resin concentration and decreased with increasing percentage of dioxane. Activation parameters were evaluated and trends of variation in these parameters and in hydrolysis rates have been discussed in terms of solvation effects and the dielectric behaviour of the medium. |
