مطالعه اثر كاربرد فرآيند نفوذ بخار بر افزايش پيشرفت واكنش توليد ايزوپروپيل پروپيونات

چكيده انگليسي :

A Study of the Effect of the Vapor Permeation Process on the Enhancement of Isopropyl Propionate Production Reaction Elham Ameri amerielham@yahoo com Date of Submission Aug 14 2010 Department of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran 1st Supervisor Ahmad Moheb ahmad@cc iut ac ir 2st Supervisor Shapoor Roodpeyma shapoor@cc iut ac ir Department Graduate Coordinator Hamid Zilouei Deparment of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Deparment of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Abstract In this study the esterification of isopropanol and propionic acid in a system coupled with the vapor permeation process was investigated For this purpose two different commercial membranes a tubular NaA zeolite membrane and a flat polymeric membrane PERVAP 2201 were used in the vapor permeation module to remove water from the reaction atmosphere during the synthesis of isopropyl propionate The reaction was carried out in a batch reactor using 3 wt relative to propionic acid of para toluene sulfonic acid PTSA and 3 4 10 and 12 wt of Amberlyst 15 as catalyst Adding the membrane process with both the zeolite and polymeric membranes significantly increased acid conversion during the reaction For example for the reaction with PTSA as catalyst the equilibrium conversion without using membrane process reached about 72 at the alcohol acid molar ratio of 1 5 1 But adding the membranes process to the system for simultaneous selective water removal form reaction media gave complete acid conversion in a reasonable shorter time Study on the effect of alcohol acid molar ratio with three different values of 1 1 1 5 1 and 3 1 showed that this ratio had considerable effect on the acid conversion and on the amount of remained water in the reaction mixture during the process The highest reaction rate was seen for alcohol acid molar ratio of 1 5 1 for all configurations of the membranes and catalysts However increasing this ratio from 1 5 1 to 3 1 did not make a positive effect on the reaction conversion but rather decreased it The effect of catalyst loading was investigated by varying the catalyst weight of Amberlyst 15 from 3 to 12 wt It was found that increasing catalyst loading had a significant positive effect on the acid conversion which was in agreement with the findings of other researchers In general in the hybrid process with high acid conversion the zeolite membrane showed superior results due to the swelling effects for the polymeric membrane at aqueous mixture Moreover based on the mechanism of the esterification reaction extra acid conversions were obtained by using PTSA as the catalyst For example at the same experimental conditions using 3 wt of Amberlyst 15 and PTSA as catalysts gave 50 and nearly 100 of acid conversions after 180 and 140 minutes from beginning of the process respectively No specific trend was observed in the results obtained for the separation factors This was due to the fact that separation factor in the coupled process was affected by two phenomena of reaction and separation These two processes are influenced by some parameters such as the rate of vapor production the initial alcohol acid molar ratio of the reactants and its effect on the boiling point of the mixture which in turn caused large variation seen in the values of the separation factor Keywords Esterification Membrane Reactor Zeolite Membrane PERVAP 2201 Isopropyl propionate

عامري، الهام

مطالعه اثر كاربرد فرآيند نفوذ بخار بر افزايش پيشرفت واكنش توليد ايزوپروپيل پروپيونات

استري شدن , راكتور غشايي , غشاء زئوليتي , PERV Ap 2201