Effect of temperature on tribological properties of palm biodiesel A.S.M.A. Haseeb, S.Y. Sia, M.A. Fazal * , H.H. Masjuki Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia article info Article history: Received 29 June 2009 Received in revised form 30 November 2009 Accepted 1 December 2009 Available online 16 December 2009 Keywords: Wear Friction Four ball Lubricity Biodiesel Diesel abstract Biodiesel, as an alternative fuel is steadily gaining attention to replace petroleum diesel partially or completely. The tribological performance of biodiesel is crucial for its application in automobiles. In the present study, effect of temperature on the tribological performance of palm biodiesel was investigated by using four ball wear machine. Tests were conducted at temperatures 30, 45, 60 and 75  C, under a normal load of 40 kg for 1 h at speed 1200 rpm. For each temperature, the tribological properties of petroleum diesel (B0) and three biodiesel blends like B10, B20, B50 were investigated and compared. During the wear test, frictional torque was recorded on line. Wear scars in tested ball were investigated by optical microscopy. Results show that friction and wear increase with increasing temperature. Ó 2009 Elsevier Ltd. All rights reserved. 1. Introduction Biodiesel, as an alternative fuel derived from vegetable oils or animal fats, has a number of technical advantages over conven- tional petroleum diesel. These include reduction of exhaust emis- sions and biodegradability, higher flash point, reduced toxicity, derivation from a renewable feedstock, and domestic origin [1–4]. It can be used in diesel engine with little or no modification [5]. Although these attributes of biodiesel have drawn attention as an alternative fuel, there exist some significant drawbacks which have limited its commercial applications. These include oxidation instability as a consequence of changing temperature as well as exposure to air, lower volatility, moisture absorption, reactivity of unsaturated hydrocarbon chains [6–8]. These characteristics of biodiesel are more prone to influence the lubrication parameters and wear of various engine components. The impact of these issues will also depend on different concentration of biodiesel in diesel blends. Besides, the adaptation of a selected alternative fuel to suit diesel engine is considered more economically attractive in using it as blend with diesel fuel than in its pure form [9–11]. It was reported that neat biodiesel possesses inherently better lubricity than conventional diesel [6]. Such effectiveness was also reported for even lower (<1%) blend levels [12–14] or higher (10–20%) levels [15,16]. Masjuki and Maleque [17], found that above 5% palm oil methyl ester (POME) in lubricant caused oxidation and corrosion. According to Maleque et al. [18], for 5% POME in lubricant, the total acid number (TAN) increases at higher temperature. They found that at higher temperature, oxidation of the lubricants caused increased wear. These results seem to imply that different temperature have different impact on lubricity for different blended fuels. The present study aims to investigate the effect of temperature on the lubricity for different palm biodiesel blends. Results obtained are expected to help in understanding the wear of fuel system parts where the operating temperature can be as high as 44–84  C [19]. 2. Experimental The tribological performance of POME was investigated by four ball wear machine. The test ball material was chrome alloy steel (E- 52100 with grade 25 extra polish) containing (0.95–1.10)% carbon and (1.3–1.6)% chromium. POME used in this study was provided from WESCHEM Technology Sdn Bhd and meets EN14214 specifi- cations (Table 1). The wear and friction characteristics of biodiesel blends were investigated at four different temperatures viz, 30, 45, 60 and 75  C, under a normal load of 40 kg for 1 h at speed 1200 rpm. The blends B10, B20, B50 were made on volume basis and stored in glass bottles at room temperature. The balls had a diameter of 12.7 mm. * Corresponding author. Tel.: þ60 3 79674448; fax: þ60 3 79675317. E-mail addresses: haseeb@um.edu.my (A.S.M.A. Haseeb), shang1627@yahoo. com (S.Y. Sia), jewel_mme.buet@yahoo.com (M.A. Fazal), masjuki@um.edu.my (H.H. Masjuki). Contents lists available at ScienceDirect Energy journal homepage: www.elsevier.com/locate/energy 0360-5442/$ – see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.energy.2009.12.001 Energy 35 (2010) 1460–1464