| Summary: | 碩士 === 國立臺灣科技大學 === 化學工程系 === 98 === The heterogeneous kinetics behavior was investigated with a batch reactor for the synthesis of propylene glycol monomethyl ester acetate (PGMEA) and propylene glycol monomethyl ether propionate (PMP) over cation-exchange resins, Amberlyat 36. The experiments were conducted at tempertures from 343.15 K to 388.15 K. Additionally, the effects of molar ratio of propylene glycol monomethyl ester(PGME) to acids in the feed stream , the mass transfer resistance on the catalytic reaction and the different levels of catalyst loadings were also observed.
The reaction rate of acids increased with increase of reaction temperature, molar ratio of PGME to acids in the feed stream, catalyst loading and rotational speed. Furthermore, the equilibrium conversion of acids increased with increase of reaction temperature and molar ratio of methanol to acids in the feed stream. The relative adsorption strengths of the reacting species were determined by adsorption experiments. The results for the synthesis of PGMEA and PMP indicated that the magnitude of adsorption strengths on Amberlyst 36 followed the order of water > PGME > PGMEA > acetic acid and water > propionic acid > PGME > PMP, respectively.
The kinetic data of the synthesis of PGMEA and PMP were correlated with the ideal-quasi-homogeneous (IQH), the non-ideal-quasi-homogeneous (NIQH), the Eley-Rideal (ER), the Langmuir-Hinshelwood-Hougen-Watson (LHHW) and the Langmuir-Hinshelwood-Hougen-Watson with Ka (LHHW-Ka) models, respectively. The optimal values of the kinetic parameters were determined from the data fitting. The NRTL model was used to calculate the activity coefficients for each reacting species. The LHHW model yielded the best representation for the kinetic behavior of heterogeneous catalytic synthesis of PGMEA and PMP.
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