A heterogeneous acid‐catalyzed process for biodiesel production from enzyme hydrolyzed fatty acids

Abstract

in Wiley InterScience (www.interscience.wiley.com).In this work, biodiesel synthesis via fatty acids esterification with methanol is conducted by using a heterogeneous catalyst made from cation-exchange resin. The kinetics of esterification is studied at the different levels of catalyst loading (3.65-53.6%, w/w), reaction temperature (333-353 K) and molar ratio of methanol to fatty acids (1:1 to 20:1). The reaction rate and fatty acids conversion increased with increases in catalyst loading, reaction temperature and molar ratio of feeding reactants. A pseudo-homogeneous kinetic model coupling the effect of catalyst loading, reaction temperature and methanol/fatty acids molar ratio used for describing the process gave a correlation coefficient of 0.95 between experimental and predicted data. The proposed model was further used to predict the optimal operating condition for obtaining equilibrium conversion of 0.99. A reaction temperature of 372.15 K, molar ratio of feeding reactants of 14.9:1 and reaction time of 9.5 h was numerically calculated as the optimal operating condition. Under this optimal operating condition, an experimental verification was carried out and a satisfactory match was observed between experimental data and model prediction.

Catalytically Upgrading Bio-oil via Esterification

“…Song et al 41 reported a similar result of the temperature effect. The kinetic model was built on the following assumptions: 42,43 (1) The rate of non-catalyzed reactions is negligible compared to that of the catalyzed reations. Under these conditions, the reactions were considered to be second-order in the forward and reverse directions.…”

Catalytic upgrading of citric acid to environmental friendly tri-butyl citrate plasticizer over ultra stable phosphonated Y zeolite

“…The steep increase in CA conversion from 34 to 89% and TBC yield from 6 to 58% with increase in molar ratio from 1:4 to 1:10 was obtained. The higher CA conversion and yield of TBC may be attributed to occupancy of the CA over the active sites present on catalyst surface and the availability of n-butanol molecules for further esterification (Su et al, 2008). Also, at a molar ratio of CA to nbutanol of 1:10, the CA may be chemisorbed on the active sites of catalysts to form carbonium ions.…”

Esterification of acidified oil with methanol by SPES/PES catalytic membrane

“…The P-H model was found to fit the experimental data fairly well. For example, Su et al used the cation-exchange resin as the acidic catalyst to investigate the esterification kinetics under different conditions (Su et al, 2008). The results showed that the optimal operating condition for obtaining FFAs conversion of 0.99 could be predicted by the P-H kinetic model.…”