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Evaluation of antioxidants on the thermo-oxidative stability of soybean biodiesel

Journal of Thermal Analysis and Calorimetry (Impact Factor: 1.98). 07/2012; DOI: 10.1007/s10973-012-2650-6

ABSTRACT This work shows the evaluation of three anti-oxidants (2,6-di-t-butyl-4-methylphenol (BHT)—synthetic antioxidant, hydrogenated cardanol (HC), and alkyl hydrogenated cardanol (AHC)—both derived from cashew nut shell liquid) on the thermo-oxidative stability of the soybean biodiesel. The antioxidants were added at con-centrations of 200, 300, and 400 ppm, and the oxidative stability of the biofuel with and without antioxidants were investigated by thermogravimetric analysis (TG-DTG and IPDT) and Metrohm 743 Rancimat per the EN 14112 method. The results showed that all antioxidants contrib-uted for the thermo-oxidative stability of the soybean biodiesel as follows: soybean biodiesel \ soybean biodie-sel ? BHT \ soybean biodiesel ? HC \ soybean biodie-sel ? AHC. In the Rancimat method, the results showed that the antioxidants influenced the biodiesel stability with an increase of at least 71 %.

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