Esterification and Deacidification of a Waste Cooking Oil (TAN 68.81 mg KOH/g) for Biodiesel Production

Energies

Jincheng Ding¹  Zheng Xia² 

[1] College of Chemical Engineering, Shandong University of Technology, Zibo, Shandong 255049, China;Pharmaceutical & Biological Engineering Department, Zibo Vocational Institute, Zibo, Shandong 255314, China; E-Mail:

关键词: biodiesel;    deacidification;    esterification;    free fatty acids;    waste cooking oil;   

DOI  :  10.3390/en5082683

来源: mdpi

【 摘 要 】

Oils with high content of free fatty acid (FFA) can be treated by acid esterification where an alcohol reacts with the given oil in the presence of acid catalyst. The investigated parameters include methanol to oil ratio, temperature and amount of catalyst. The optimum conditions for acid esterification which could reduce FFA content in the feedstock to less than 1.88% (acid value 3.76 mg KOH/g waste cooking oil) were 50 °C, 20% methanol to oil ratio (by volume) and 0.4 vol.% H₂SO₄ after 5 h. However, oil with an acid value of more than 1 mg KOH/g oil cannot meet the alkaline catalyzed transesterification conditions. Under the conditions of NaOH concentration 0.5 N, excess alkali 15%, 60°C, 40 min, the FFA removal rate for deacidification reached 77.11% (acid value 0.86 mg KOH/g esterified oil). The acid value of deacidification product was reduced below 0.86 mg KOH/g esterified oil, thus meeting the base-catalyzed trans-esterification conditions.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland.