Optimization of pretreatment of jatropha oil with high free fatty acids for bio...

• Author(s): Suwito, Supriyono ; Dragone, Giuliano ; Sulistyo, Hary ; Murachman, Bardi ; Purwono, Suryo ; Teixeira, J. A.
• Date: 2012
• Persistent ID: http://hdl.handle.net/1822/22139
• Origin: RepositóriUM - Universidade do Minho
• Subject(s): Biodiesel; Biofuel; Esterification; Free fatty acids; Jatropha curcas oil
• Document Type: Article
• Language: English

Description

A central composite rotatable design and response surface methodology were used in order to investigate the individual and combined effects of the ethanol-to-oil ratio, H2SO4 concentration, temperature and time of reaction on the reduction of free fatty acid (FFA) in jatropha oil. A quadratic polynomial model relating the reaction variables with FFA reduction was developed, presenting a good coefficient of determination (R2= 0.893). For reducing FFA to less than 1%, the optimal combination was found to be 0.62 v$v–1 ethanol-to-oil ratio (14.9 v$v–1 ethanol-to-FFA ratio), 1.7% v$v–1 H2SO4 concentration,and 79 min reaction time at a reaction temperature of 54°C. These results are of great relevance to maximize methyl esters formation by transesterification using an alkaline catalyst.