Energies 2008, 1, 3-18; DOI: 10.3390/en1010003
Waste Cooking Oil as an Alternate Feedstock for Biodiesel
Arjun B. Chhetri 1, K. Chris Watts 2 and M. Rafiqul Islam 1,* 1
Civil and Resources Engineering Dalhousie University, Room D510, 1360 Barrington St., Box 1000, Halifax, N.S. B3J 2X4, Canada; E-mail: firstname.lastname@example.org (for Arjun B. Chhetri) 2
Process Engineering, Dalhousie University, Halifax, NS, Box 1000, Halifax, N.S. B3J 2X4, Canada; Tel. (902) 494-3269; Fax 420-7639; E-mail: email@example.com * Author to whom correspondence should be addressed; E-mail: firstname.lastname@example.org Received: 27 March 2008 / Accepted: 9 April 2008 / Published: 10 April 2008
Abstract: As crude oil price reach a new high, the need for developing alternate fuels has become acute. Alternate fuels should be economically attractive in order to compete with currently used fossil fuels. In this work, biodiesel (ethyl ester) was prepared from waste cooking oil collected from a local restaurant in Halifax, Nova Scotia, Canada. Ethyl alcohol with sodium hydroxide as a catalyst was used for the transesterification process. The fatty acid composition of the final biodiesel esters was determined by gas chromatography. The biodiesel was characterized by its physical and fuel properties including density, viscosity, acid value, flash point, cloud point, pour point, cetane index, water and sediment content, total and free glycerin content, diglycerides and monoglycerides, phosphorus content and sulfur content according to ASTM standards. The viscosity of the biodiesel ethyl ester was found to be 5.03 mm2/sec at 40oC. The viscosity of waste cooking oil measured in room temperature (at 21° C) was 72 mm2/sec. From the tests, the flash point was found to be 164oC, the phosphorous content was 2 ppm, those of calcium and magnesium were 1 ppm combined, water and sediment was 0 %, sulfur content was 2 ppm, total acid number was 0.29 mgKOH/g, cetane index was 61, cloud point was -1oC and pour point was -16oC. Production of biodiesel from waste cooking oils for diesel substitute is particularly important because of the decreasing trend of economical oil reserves, environmental problems caused due to fossil fuel use and the high price of petroleum products in the international market.
Energies 2008, 1
Keywords: Waste cooking oil, alternate energy, biodiesel, feedstock, fuel characterization
Increasing uncertainty about global energy production and supply, environmental concerns due to the use of fossil fuels, and the high price of petroleum products are the major reasons to search for alternatives to petrodiesel. Lean  claimed that the global supply of oil and natural gas from the conventional sources is unlikely to meet the growth in energy demand over the next 25 years. In this perspective, considerable attention has been given towards the production of biodiesel as a diesel substitute. Moreover, biodiesel fuel has become more attractive because of its environmental benefits , due to the fact that plants and vegetable oils and animal fats are renewable biomass sources. Biodiesel represents a largely closed carbon dioxide cycle (approximately 78%), as it is derived from renewable biomass sources. Compared to petroleum diesel, biodiesel has lower emission of pollutants, it is biodegradable and enhances the engine lubricity  and contributes to sustainability [3,4]. Biodiesel has a higher cetane number than diesel fuel, no aromatics, no sulfur, and contains 10–11% oxygen by weight .
Use of neat (unprocessed) vegetable oils in the compression ignition engines is reported to cause several problems due to its high viscosity . Biodiesel which is accepted as an attractive alternative fuel, is prepared by transesterification of vegetable oils and animal fats with an alcohol in presence of a catalyst. However, the land use for production...
Please join StudyMode to read the full document