Ferric sulphate catalysed esterification of free fatty acids in waste cooking oil.
In this work, the esterification of free fatty acids (FFA) in waste cooking oil catalysed by ferric sulphate was studied as a pre-treatment step for biodiesel production. The effects of reaction time, methanol to oil ratio, catalyst concentration and temperature on the conversion of FFA were investigated on a laboratory scale. The results showed that the conversion of FFA reached equilibrium after an hour, and was positively dependent on the methanol to oil molar ratio and temperature. An optimum catalyst concentration of 2 wt.% gave maximum FFA conversion of 59.2%. For catalyst loadings of 2 wt.% and below, this catalysed esterification was proposed to follow a pseudo-homogeneous pathway akin to mineral acid-catalysed esterification, driven by the H(+) ions produced through the hydrolysis of metal complex [Fe(H(2)O)(6)](3+) (aq).
Gan
Suyin
S
Department of Chemical and Environmental Engineering, The University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor Darul Ehsan, Malaysia. suyin.gan@nottingham.edu.my
Ng
Hoon Kiat
HK
Ooi
Chun Weng
CW
Motala
Nafisa Osman
NO
Ismail
Mohd Anas Farhan
MA
D002384:Catalysis; D003296:Cooking; D004951:Esterification; D005230:Fatty Acids, Nonesterified / Q000378:metabolism*; D005290:Ferric Compounds / Q000737:chemistry*; D000432:Methanol / Q000737:chemistry; D010938:Plant Oils / Q000737:chemistry*; D015203:Reproducibility of Results; D013696:Temperature; D013997:Time Factors; D014866:Waste Products / Q000032:analysis*
D005230:Fatty Acids, Nonesterified; D005290:Ferric Compounds; D010938:Plant Oils; D014866:Waste Products; C024823:ferric sulfate; D000432:Methanol