Influence of drying processes on oxidative stability of ethyl corn biodiesel by differential scanning calorimetry
- 138 Downloads
The influence of drying processes in the biodiesel oxidation was investigated by means of the oxidative induction time obtained from differential scanning calorimetry data. For this purpose, corn biodiesel was dried by different methods including: chemical (anhydrous sodium sulfate) and thermal (induction heating, heating under vacuum and with microwave irradiation). The drying efficiency was evaluated by monitoring IR absorption in the 3,500–3,200 cm−1 range and by the AOCS Bc 2-49 method. In general, the oxidative induction times increased inversely to the heating degree, except that of microwave irradiation, which was selective to water evaporation and caused low impact over the unsaturation of biodiesel. The DSC technique was shown to be a powerful tool to evaluate with high level of differentiation the influence of the drying process on the oxidative stability of biodiesel.
KeywordsBiodiesel Humidity Oxidative stability DSC
The authors acknowledge CNPq and UEMA for the financial support of this work.
- 5.Conceição MM, Candeia RA, Silva FC, Bezerra AF, Fernandes Jr VJ, Souza AG. Thermoanalytical characterization of castor oil biodiesel. Renew Sustain Energy Rev. 2007;11:964–75.Google Scholar
- 6.Ramalho VC, Jorge N. Antioxidantes utilizados em óleos, gorduras e alimentos gordurosos. Quím Nova. 2006;29:755–60.Google Scholar
- 7.Backtorp C, Hagvall L, Borje A, Karlberg A, Norrby P, Nyman G. Mechanism of air oxidation of the fragrance terpene geraniol. J Chem Theory Comput. 2008;4:101–6.Google Scholar
- 9.Velasco J, Andersen ML, Skibsted LH. Evaluation of oxidative stability of vegetable oils by monitoring the tendency to radical formation. A comparison of electron spin resonance spectroscopy with the Rancimat method and differential scanning calorimetry. Food Chem. 2004;85:623–32.CrossRefGoogle Scholar
- 15.Andrade JM, Dantas MB, Vasconcelos AFF, Keyson D, Santos CCL, Costa ASG, et al. Produção de Biodiesel de Óleo de Milho Utilizando Microondas e o Método Convencional. II Congresso da Rede Brasileira de Tecnologia de Biodiesel. 2007;2:154.Google Scholar
- 16.American Oil Chemical Society (AOCS). Official methods and recommended practices, 4th ed. Champaign, 2 (1990).Google Scholar
- 21.Dunn RO. Oxidative stability of biodiesel by dynamic mode pressurized-differential scanning calorimetry (P-DSC). Fuel Process Technol. 2005;49(5):1633–41.Google Scholar