(81d) Investigating the Effect of Baffles on CSTR Performance for Liquid Phase Reaction

In this work, the
effect of baffles on the performance of CSTR was investigated experimentally
under different operating conditions. The results obtained for baffled reactor
were analyzed and compared with data obtained in case of absence of baffles. The
operating conditions considered for investigation are temperature, feed flow
rate, reactor volume, and residence time and stirrer rate. The effect of
operating conditions on the reaction conversion and specific rate constant has
been studied for liquid phase hydrolysis of sodium hydroxide with ethyl acetate.
Experiments were conducted at concentrations of 0.1 M NaOH and 0.1 M CH₃COOC₂H₅
and at a pressure of 1 atmosphere. Reaction conversion of 48.6 % and specific
rate constant equal to 4.89 dm³/mol.sec was obtained in the presence
of baffles in the reactor system as compared to conversion of 48.2 % and
specific rate constant of 4.78 x10^-3 dm³/mol.sec in case
of without baffles under steady state conditions highlighting the industrial
importance of baffles. The conversion and specific rate constant increases with
increase of temperature both with and without baffles, moreover baffled CSTR
contributes to higher conversion. Reaction conversion of 63.4 % with baffles
was noticed as compared to lower value of 61.12 % under constant operating
conditions of reactant flow rate, concentration, reactor volume and stirrer
rate. Conversion and specific rate constant increase as function of stirrer
rate and conversion and specific rate constant of 54.2% and 6.80 dm³/mol.sec
respectively were obtained for baffled CSTR as compared to lower conversion of
47.2 %  at a stirrer rate of 140 rpm. High conversion and specific rate
constant were obtained as compared with unbaffled system as a function of
reactants flow rate. Results also show that increase of reactants flow rate
leads to decrease of residence time and consequently, reaction conversion
decreases. On the other hand, it is also observed that presence of baffles
contributes negatively to the conversion as volume of reactor increases and it
is noticed that conversion of 51.8 % with baffles was obtained as compared to
conversion of 53.0% without baffles in the reactor system. It is concluded that
above findings summarize the significance of baffles and operating conditions
may be optimized to achieve maximum conversion and hence overall optimization
of chemical process for industrial level production of ethanol and sodium acetate.