Please cite this article in press as: Panchal, T., et al., Bio based grease A value added product from renewable resources. Ind. Crops Prod. (2014), http://dx.doi.org/10.1016/j.indcrop.2014.09.030 ARTICLE IN PRESS G Model INDCRO-7526; No. of Pages 5 Industrial Crops and Products xxx (2014) xxx–xxx Contents lists available at ScienceDirect Industrial Crops and Products jo ur nal home p age: www.elsevier.com/locate/indcrop Bio based grease A value added product from renewable resources Tirth Panchal, Dhiraj Chauhan, Merlin Thomas, Jigar Patel ∗ Department of Industrial Chemistry, Institute of Science and Technology for Advanced Studies and Research, V.V. Nagar, Gujarat 388120, India a r t i c l e i n f o Article history: Received 21 July 2014 Received in revised form 6 September 2014 Accepted 15 September 2014 Available online xxx Keywords: Vegetable oil Transesterification Grease Wear Friction Weld load a b s t r a c t Finite resources of crude petroleum oil and growing concern over climate change are driving investment and innovation in the sector of biofuels. Vegetable oils in comparison with mineral oils are renewable, easily available, environmentally friendly, economically cheaper than mineral oil and hence sustainable indeed. This paper presents a series of structural modifications of vegetable oil–Karanja oil using various alcohols to form fatty acid esters. This fatty acid esters were then used as base oil in the formulation of grease. Formulated bio-based grease was then evaluated for its tribological properties against mineral oil based grease. © 2014 Elsevier B.V. All rights reserved. 1. Introduction Global grease consumption is estimated at 1296 KT of which industrial applications accounts for 691 KT. Mineral oil based greases account for close to 90% of the global demand, while 9% of synthetic esters is used and only 1% of bio degradable base oils are used for manufacturing of greases. It is assumed that global con- sumption of grease in industrial application will be up to 758 KT till 2017 (Sharma and Phadke, 2014). The question of sustainability as related to industrial lubricants is an interesting dichotomy. By the very nature of being based on crude oil as a raw material for both mineral oil based and synthetic ester based lubricants, lubri- cants appear to be the antithesis of sustainability. Crude oil is a finite resource that is fully consumed in the conversion process to a usable lubricant. All over the globe usage and disposal of lubricants has to fulfill the need to protect the environment. Manufacturing and application of eco-destructive lubricants should be decreased as much as possible (Waara et al., 2001). Since 1970s environmen- tal impact of lubricants, both in their manufacture and application, has attracted increasing attention toward environment protection policies (Bartz, 1998). Recently, due to the urge to protect the envi- ronment, the sulfur element of the automotive fuels is restricted within 10 ppm (Xu et al., 2014). Along with the finiteness of crude petroleum its detrimental effects over environment makes every- one look toward renewable resources as they are easily available, ∗ Corresponding author. Tel.: +91 989 826 1951; fax: +91 2692234955. E-mail addresses: pramukhprit@yahoo.co.in, pramukhprit@gmail.com (J. Patel). environmentally friendly and hence sustainable indeed (Zulkifli et al., 2013; Asadauskas and Erhan, 1999; Beran, 2008). Bio-lubes play an integral part in the overall scheme of sus- tainable lubrication. Sourced from plants or organisms that can replenish themselves, this class of lubricant seems poised to become the focus of sustainable lubrication. Vegetable oils, as renewable resources, are gradually used as green raw materials in various areas of research in bio based lubricants (Salimon and Salih, 2009). Vegetable oils as compared to mineral oils have differed in physicochemical as well as tribological properties due to the pres- ence of triglyceride in its chemical structure. High flash point over 300 ◦ C classifies vegetable oils to non-flammable liquids. Also, they have good lubricity, viscosity indices, superior film strength and affinity to metal surfaces (Fox and Stachowiak, 2007; Doll et al., 2007). In addition, vegetable oils have high solubilizing power for polar contaminants and additive molecules (Dinda et al., 2008). On the other side vegetable oils lags behind in thermo-oxidative and hydrolytic stability which makes them incapable to be used directly as lubricant as compared to petroleum based oils. These drawbacks of vegetable oil can be overcome by chemically modifying vegetable oils. Researchers have developed various routes to chemically mod- ify vegetable oil and use it as bio-lubricant. These modification involves transesterification (Masood et al., 2012; Bokade and Yadav, 2007; Gryglewicz et al., 2003), epoxidation (Salimon and Salih, 2010; Adhvaryu and Erhan, 2002), enzyme catalyzed esterifica- tion (Uosukainen et al., 1998; Dossata et al., 2002; Stergiou et al., 2013) and estolide formation (Cermak et al., 2013; García-Zapateiro et al., 2013). Various methods for formulating grease using http://dx.doi.org/10.1016/j.indcrop.2014.09.030 0926-6690/© 2014 Elsevier B.V. All rights reserved.