Review Biodiesel production from jatropha oil by catalytic and non-catalytic approaches: An overview Joon Ching Juan a,⇑ , Damayani Agung Kartika a , Ta Yeong Wu b , Taufiq-Yap Yun Hin c a Laboratory of Applied Catalysis and Environmental Technology, School of Science, Monash University, Bandar Sunway 46150, Malaysia b Chemical and Sustainable Process Engineering Research Group, School of Engineering, Monash University, Bandar Sunway 46150, Malaysia c Centre of Excellence for Catalysis Science and Technology, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan, Malaysia article info Article history: Received 24 May 2010 Received in revised form 15 September 2010 Accepted 16 September 2010 Available online 1 October 2010 Keywords: Biodiesel Catalyst Ester Jatropha oil Transesterification abstract Biodiesel (fatty acids alkyl esters) is a promising alternative fuel to replace petroleum-based diesel that is obtained from renewable sources such as vegetable oil, animal fat and waste cooking oil. Vegetable oils are more suitable source for biodiesel production compared to animal fats and waste cooking since they are renewable in nature. However, there is a concern that biodiesel production from vegetable oil would disturb the food market. Oil from Jatropha curcas is an acceptable choice for biodiesel production because it is non-edible and can be easily grown in a harsh environment. Moreover, alkyl esters of jatropha oil meet the standard of biodiesel in many countries. Thus, the present paper provides a review on the transesterification methods for biodiesel production using jatropha oil as feedstock. Crown Copyright Ó 2010 Published by Elsevier Ltd. All rights reserved. 1. Introduction Energy is a basic requirement for every sector of economic development in a country. As a result, energy demands have been steadily increasing along with the growth of human population and industrialization. Common sources of energy are petroleum, natural gas and coal from fossil fuels. This growing consumption of energy has rapidly depleted non-renewable sources of energy. Rising price of fossil-based fuels and potential shortage in the future have led to a major concern about the energy security in every country (Agarwal and Agarwal, 2007; Jain and Sharma, 2010a; Jayed et al., 2009; Robles-Medina et al., 2009). Moreover, there are many disadvantages of using fossil-based fuels, such as atmospheric pollution and environmental issues. Fossil fuels emis- sions are major contributors of greenhouse gases which may lead to global warming. Combustion from fossil fuels is major source of air pollutants, which consist of CO, NO x , SO x , hydrocarbons, particulates and carcinogenic compounds (National Biodiesel Board, 2010; Diwani et al., 2009). Fig. 1 shows the comparison between pollutants emitted from petro-diesel engine and biodiesel engine. The disadvantages and shortages of fossil fuels have moti- vated many researchers to find an alternative source of renewable energy. At present, diesel-powered vehicles represent about one-third of vehicles sold in Europe and United States (Jayed et al., 2009). The global consumption of petroleum diesel is 934 million tonnes per year (Kulkarni and Dalai, 2006). Biodiesel is one of the most promising alternative fuels for diesel engines. The demand of biodiesel has significantly increased from 2005 especially in USA (Pahl, 2008). Biodiesel is defined as a fuel comprising of mono- alkyl esters of long chain fatty acids derived from vegetable oil or animal fat (Su and Wei, 2008). There are several advantages of biodiesel as compared to conventional diesel. Advantages of biodiesel are (1) It helps to reduce carbon dioxide and other pollutants emission from engines, (2) Engine modification is not needed as it has similar properties to diesel fuel, (3) It comes from renewable sources whereby people can grow their own fuel, (4) Diesel engine performs better on biodiesel due to a high cetane number, (5) High purity of biodiesel would eliminate the use of lubricant, (6) Biodiesel production is more efficient as compared to fossil fuels as there will be no underwater plantation, drilling and refinery and (7) Biodiesel would make an area become independent of its need for energy as it can be produced locally (Jain and Sharma, 2010a; Jayed et al., 2009; Nie et al., 2006; Robles-Medina et al., 2009; Shah et al., 2004; Su and Wei 2008; Vieira et al., 2006). There are three types of oil as potential sources for biodiesel production, which are vegetable oil, animal fat and used cooking oil. Animal fat is infeasible because it becomes solid wax at room temperature and causes problems during the production process 0960-8524/$ - see front matter Crown Copyright Ó 2010 Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.biortech.2010.09.093 ⇑ Corresponding author. Tel.: +60 3 5514 6106; fax: +60 3 5514 6364. E-mail address: juan.joon.ching@sci.monash.edu.my (J.C. Juan). Bioresource Technology 102 (2011) 452–460 Contents lists available at ScienceDirect Bioresource Technology journal homepage: www.elsevier.com/locate/biortech