*Article* **Biodiesel Purification by Solvent-Aided Crystallization Using 2-Methyltetrahydrofuran**

**Wan Nur Aisyah Wan Osman 1,2, Nur Athirah Izzati Badrol <sup>1</sup> and Shafirah Samsuri 1,2,\***


**\*** Correspondence: shafirah.samsuri@utp.edu.my

**Abstract:** The previous biodiesel purification by Solvent-Aided Crystallization (SAC) using 1-butanol as assisting agent and parameters for SAC were optimized such as coolant temperature, cooling time and stirring speed. Meanwhile, 2-Methyltetrahydrofuran (2-MeTHF) was selected as an alternative to previous organic solvents for this study. In this context, it is used to replace solvent 1-butanol from a conducted previous study. This study also focuses on the technological improvements in the purification of biodiesel via SAC as well as to produce an even higher purity of biodiesel. Experimental works on the transesterification process to produce crude biodiesel were performed and SAC was carried out to purify the crude biodiesel. The crude biodiesel content was analyzed by using Gas Chromatography–Mass Spectrometry (GC-MS) and Differential Scanning Calorimetry (DSC) to measure the composition of Fatty Acid Methyl Esters (FAME) present. The optimum value to yield the highest purity of FAME for parameters coolant temperature, cooling time, and stirring speed is −4 ◦C, 10 min and 210 rpm, respectively. It can be concluded that the assisting solvent 2-MeTHF has a significant effect on the process parameters to produce purified biodiesel according to the standard requirement.

**Keywords:** 1-butanol; 2-methyltetrahydrofuran; biodiesel; coolant temperature; cooling time; green solvent; stirring speed; solvent-aided crystallization
