The external mass transfer model for the hydrolysis of palm olein using immobilized lipase in a scaled-up recirculated packed-bed reactor

An external mass transfer model has been developed for immobilized lipase at small scale, which is J_D = 0.093Re^-0.5. However, this developed model has not been validated at a larger scale before it can be applied in the industry. Thus, the objective of this study is to validate the external mass transfer model for the hydrolysis of palm olein using immobilized lipase in a scaled-up recirculated packed-bed batch reactor (RPBBR). The hydrolysis of palm olein in RPBBR was run at different flow rates. The values of the mass transfer coefficient, k_m from experiments were compared with the value of k_m calculated from theoretical. From the result, percent error between theoretical k_m values and experimental k_m values were around 2% to 30% for different flow rates. One correction had been made on the external mass transfer model for the immobilized lipase in the packed-bed reactor to increase the accuracy of the model. The form of the more accurate external mass transfer model for immobilized lipase in the packed-bed reactor for a scaled-up RPBBR is J_D = 0.093xRe^-0.5, where x is a correction factor. The average value of the correction factor, x found is 1.194725. This work can be further investigated to involve higher concentration using a more complete kinetic model such as ping-pong bi-bi model and Michaelis-Menten model as well as the surface modification of enzyme.