Esterification of acidified oil with methanol by SPES/PES catalytic membrane.
A sulfonated polyethersulfone (SPES)/polyethersulfone (PES) blend catalytic membrane was prepared and used as a heterogeneous catalyst in the esterification of the acidified oil (acid value 153 mg KOH/g) with methanol for producing biodiesel. The results showed that the free fatty acids conversion reached 97.6% using SPES/PES catalytic membrane under the optimal esterification conditions. Meanwhile, the SPES/PES membrane with 20.3% degree of sulfonation showed a good catalytic stability. A pseudo-homogeneous kinetic model was established. The results indicated that the reaction rate constant increased with increasing methanol/acidified oil molar ratio, the loading of catalytic membrane and reaction temperature. The reaction order was 2 and the activation energy decreased from 74.65 to 21.07 kJ/mol with increasing catalytic membrane loading from 0 to 0.135 meq/g(oil). It implies that the esterification is not diffusively controlled but kinetically controlled. The predicted results were in good agreement with the experimental data.
State Key Laboratory of Hollow Fiber Membrane Materials and Processes, School of Materials Science and Engineering, Tianjin Polytechnic University, Tianjin 300160, PR China.
Wenying
W
Shi
Benqiao
B
He
Jianxin
J
Li
D000143:Acids / Q000737:chemistry*; D002384:Catalysis; D004951:Esterification; D005230:Fatty Acids, Nonesterified / Q000138:chemical synthesis; D007700:Kinetics; D008567:Membranes, Artificial; D000432:Methanol / Q000737:chemistry*; D008956:Models, Chemical; D009821:Oils / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013450:Sulfones / Q000737:chemistry*; D013451:Sulfonic Acids / Q000737:chemistry*; D013696:Temperature
D000143:Acids; D005230:Fatty Acids, Nonesterified; D008567:Membranes, Artificial; D009821:Oils; D011108:Polymers; D013450:Sulfones; D013451:Sulfonic Acids; C022840:polyether sulfone; D000432:Methanol