References
- Alejandre , A. G. , Cruza , M. G. , Trombetta , M. , Busca , G. and Ramíreza , J. 1998 . Characterization of alumina–titania mixed oxide supports. Part II: Al2O3-based supports . Microporous & Mesoporous Mater. , 23 : 265 – 275 .
- Chai , F. , Cao , F. , Zhai , F. , Chen , Y. , Wang , X. and Su , Z. 2007 . Transesterification of vegetable oil to biodiesel using a heteropolyacid solid catalyst . Adv. Synth. & Catal. , 349 : 1057 – 1065 .
- Demirbas , A. 2007 . Importance of biodiesel as transportation fuel . Energy Policy , 35 : 4661 – 4670 .
- Demirbas , A. H. and Demirbas , I. 2007 . Importance of rural bioenergy for developing countries . Energy Convers. & Mgmt. , 48 : 2386 – 2398 .
- Furuta , S. , Matsuhashi , H. and Arata , K. 2004 . Biodiesel fuel production with solid superacid catalysis in fixed bed reactor under atmospheric pressure . Catal. Commun. , 5 : 721 – 723 .
- Huber , G. W. , Iborra , S. and Corma , A. 2006 . Synthesis of transportation fuels from biomass: Chemistry, catalysts, and engineering . Chem. Rev. , 106 : 4044 – 4048 .
- Jitputti , J. and Kitiyanan , B. 2006 . Transesterification of crude palm kernel oil and crude coconut oil by different solid catalysts . Chem. Engrg. J. , 116 : 61 – 66 .
- Jung , Y. S. , Kim , D. W. , Kim , Y. S. , Park , E. K. and Baeck , S. H. 2008 . Synthesis of alumina–titania solid solution by sol–gel method . J. Phys. & Chem. Solids , 69 : 1464 – 1467 .
- López , T. , Bosch , P. , Tzompantzi , F. , Gómez , R. and Navarrete , J. 2000 . Effect of sulfation methods on TiO2–SiO2 sol–gel catalyst acidity . Appl. Catal. , 197 : 107 – 117 .
- Lotero , E. , Liu , Y. , Lopez , D. E. , Suwannakarn , K. , Bruce , D. A. and Goodwin , J. G. Jr. 2005 . Synthesis of biodiesel via acid catalysis . Indus. & Engrg. Chem. Res. , 44 : 5353 – 5363 .
- Marchetti , J. M. , Miguel , V. U. and Errazu , A. F. 2007 . Possible methods for biodiesel production . Renew. & Sustain. Energy Rev. , 11 : 1300 – 1311 .
- Yang , Z. H. , Zhang , P. , Lian , P. Y. and Li , T. J. 2000 . Surface photovoltage behavior of porous silicon modified with SO4 specimens . Materials Chemistry and Physics , 63 : 167 – 169 .