Deacidification of <em>Pistacia</em> <em>chinensis</em> Oil as a Promising Non-Edible Feedstock for Biodiesel Production in China

Abstract

<em>Pistacia</em> <em>chinensis</em> seed oil is proposed as a promising non-edible feedstock for biodiesel production. Different extraction methods were tested and compared to obtain crude oil from the seed of <em>Pistacia</em> <em>chinensis</em>, along with various deacidification measures of refined oil. The biodiesel was produced through catalysis of sodium hydroxide (NaOH) and potassium hydroxide (KOH). The results showed that the acid value of <em>Pistacia</em> <em>chinensis</em> oil was successfully reduced to 0.23 mg KOH/g when it was extracted using ethanol. Consequently, the biodiesel product gave a high yield beyond 96.0%. The transesterification catalysed by KOH was also more complete. Fourier transform infrared (FTIR) spectroscopy was used to monitor the transesterification reaction. Analyses by gas chromatography-mass spectrometry (GC-MS) and gas chromatography with a flame ionisation detector (GC-FID) certified that the <em>Pistacia</em> <em>chinensis</em> biodiesel mainly consisted of C₁₈ fatty acid methyl esters (81.07%) with a high percentage of methyl oleate. Furthermore, the measured fuel properties of the biodiesel met the required standards for fuel use. In conclusion, the <em>Pistacia</em> <em>chinensis</em> biodiesel is a qualified and feasible substitute for fossil diesel.

Keywords

• biodiesel
• &lt;em&gt;Pistacia&lt;/em&gt; &lt;em&gt;chinensis&lt;/em&gt; seed oil
• deacidification
• transesterification