Distilled technical cashew nut shell liquid (DT-CNSL) as an effective biofuel and additive to stabilize triglyceride biofuels in diesel Shilpa Kammaradi Sanjeeva a, c , Mitchell Preetham Pinto a , Manoj Mulakkapurath Narayanan a, b , Gopalakrishna Mangalore Kini a , Chandrasekhar Bhaskaran Nair a, c , P.V. SubbaRao a , Phani Kumar Pullela a, b, c , Siva Ramamoorthy c , Colin J. Barrow b, * a Bigtec Pvt Ltd., 59th “C” cross, 4th “M” Block, Rajajinagar, Bangalore 560010, India b Centre for Chemistry and Biotechnology, Deakin University, Locked Bag 20000, Geelong, Victoria 3220, Australia c School of Bio Sciences and Technology, VIT University, Vellore, Tamil Nadu 632014, India article info Article history: Received 2 August 2013 Accepted 13 May 2014 Available online Keywords: Biofuel Cashew nut shell liquid Additive Jatropha Tallow oil Cardanol abstract We report distilled technical cashew nut shell liquid (DT-CNSL) as a non-transesterified biofuel and also as an additive to convert triglycerides to biofuel, without the need for the formation of methyl esters. DT- CNSL blends of diesel obey physico-chemical parameters of diesel. DT-CNSL offers stability to blends of straight vegetable oil (SVO) and tallow oil in diesel. Fluorescence studies using charge transfer probes show that the blend of DT-CNSL, triglycerides and diesel is a uniform solution, and fluorescence behavior is similar to that of diesel. The economics for the cultivation of cashew (Anacardium occidentale), its industrial use and rich carbon sink properties indicate that DT-CNSL could complement or replace traditional biodiesel crops like Jatropha and improve income for farmers. © 2014 Elsevier Ltd. All rights reserved. 1. Introduction Biofuel is a broad term covering any biomass-related product being used for fuel applications [1]. Biodiesel is a form of biofuel obtained by transesterification and it is typically blended with diesel [2]. Biodiesel is reported to have advantages over traditional petroleum fuels with respect to aspects of availability, pollution, and economics [2]. These include reduction in CO emission, higher cetane rating, biodegradability, and being non-toxic [3,4]. Biodiesel is also associated with some drawbacks, which have led some re- searchers to question the logic of using biodiesel for automotive applications [1,5,6]. There is increasing criticism that some biodiesel is not envi- ronmentally friendly and that the high amount of energy needed for the preparation of transesterified biodiesel from triglycerides by using methanol, sodium hydroxide and neutralization of resultant waste products results in high processing costs. Distil- lation of biodiesel can consume more energy than is obtained from its use [5,6]. Farmers cultivating Jatropha in wastelands of South Asia are increasingly realizing that the yields obtained are significantly lower than those projected by government agencies [7,8]. There are increasing reports that Jatropha leaves and seed husk cannot be used as cattle feed and traces of hydrogen cyanide present in leaves and seeds can be harmful to people associated with processing of seeds and in seed collection [9,10]. In support of this the USA Food and Drug Administration (FDA) has released an advisory in July 2012 asking all food producers to stay away from Jatropha products such as glycerol and protein byproducts [11]. Until now Jatropha producers have relied on food and pharma- ceutical applications of rich protein byproducts to offset the costs of supplying Jatropha oil to the biofuel industry, and so the toxic phorbol esters present in Jatropha products are a serious concern for the viability of this crop [12]. In India edible oils such as palm and soybean oils are banned for fuel applications and so alterna- tives to Jatropha crops need to address the issue of loss of land for use to product food crops. Abbreviations: DT-CNSLs, distilled technical cashew nut shell liquid; SVO, straight (or waste) vegetable oil; AOT, sodium bis [2-ethylhexyl] sulfosuccinate; PRODANs, N,N-dimethyl-6-propionyl-2-naphthylamine; NILE RED, 9-diethylamino- 5-benzo[a]phenoxazinone; TNPP, trinonyl phenyl phosphite; GI cans, galvanized iron cans. * Corresponding author. Tel.: þ61 3 5227 1318; fax: þ61 3 5227 1040. E-mail address: cbarrow@deakin.edu.au (C.J. Barrow). Contents lists available at ScienceDirect Renewable Energy journal homepage: www.elsevier.com/locate/renene http://dx.doi.org/10.1016/j.renene.2014.05.024 0960-1481/© 2014 Elsevier Ltd. All rights reserved. Renewable Energy 71 (2014) 81e88