Bioethanol production potential from Brazilian biodiesel co-products Evan Michael Visser a , Delly Oliveira Filho a, *, Marcio Areˆdes Martins a , Brian L. Steward b a Departamento de Engenharia Agrı´cola, Universidade Federal de Vic¸osa, Campus Universita´rio 36570-000 Vic¸osa, MG, Brazil b Department of Agricultural and Biosystems Engineering, Iowa State University, 214D Davidson Hall, Ames, IA 50011, USA article info Article history: Received 26 June 2008 Received in revised form 17 September 2010 Accepted 21 September 2010 Keywords: Biodiesel Oil crops Cellulosic ethanol production Oil extraction co-products Transesterification abstract One major problem facing the commercial production of cellulosic ethanol is the challenge of economically harvesting and transporting sufficient amounts of biomass as a feedstock at biorefinery plant scales. Oil extraction for biodiesel production, however, yields large quantities of biomass co-products rich in cellulose, sugar and starch, which in many cases may be sufficient to produce enough ethanol to meet the alcohol demands of the trans- esterification process. Soybean, castor bean, Jatropha curcas, palm kernel, sunflower and cottonseed were studied to determine ethanol production potential from cellulose found in the oil extraction co-products and also their capacity to meet transesterification alcohol demands. All crops studied were capable of producing enough ethanol for biodiesel production and, in the case of cottonseed, 470% of the transesterification demand could be met with cellulosic ethanol production from oil extraction co-products. Based on Brazilian yields of the crops studied, palm biomass has the highest potential ethanol yield of 108 m 3 km 2 followed by J. curcas with 40 m 3 km 2 . A total of 3.5 hm 3 could be produced from Brazilian soybean oil extraction co-products. ª 2010 Elsevier Ltd. All rights reserved. 1. Introduction Increasing environmental concerns in recent years have encouraged the development and use of carbon neutral biomass energy sources. Currently, biomass accounts for 9.8% of the world’s primary energy use per year [1]. However, only 30% of biomass energy is used in modern forms (e.g. genera- tion of electricity, steam and liquid bio-fuels) while the remaining 70% is used in traditional (e.g. combustion in cook stoves for domestic heating and cooking) uses [2]. The sustainable use of biomass feedstocks is obtained by using proper technologies and management techniques. Brazil is one of the world’s largest agricultural producers and is especially known for its agricultural expansion potential. Second only to the United States, Brazil is responsible for approximately 16% of world oilseed production [3]. This value only considers the production of soybean, cottonseed, peanut, sunflower and rapeseed. However, various other oil crops, such as castor bean, palm kernels and Jatropha curcas, have good potential for vegetable oil production, especially in tropical climates. World biofuel production is growing exponentially, espe- cially in countries with large agricultural programs. Brazilian ethanol production in 2008 totaled 27 hm 3 after expanding by 20% from 2007 [4]. Installed biodiesel production capacity in Brazil has reached approximately 2.5 hm 3 per year, equivalent to 82.5 PJ, but is still less than 0.2% of the biomass energy consumed in the world [5]. Vegetable oil extraction for the * Corresponding author. Tel.: þ55 31 3899 1897; fax: þ55 31 3899 2735. E-mail addresses: evanvisser@gmail.com (E.M. Visser), delly@ufv.br (D.O. Filho), aredes@ufv.br (M.A. Martins), bsteward@iastate.edu (B.L. Steward). Available at www.sciencedirect.com http://www.elsevier.com/locate/biombioe biomass and bioenergy 35 (2011) 489 e494 0961-9534/$ e see front matter ª 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.biombioe.2010.09.009