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International Journal of Engineering & Technology, 7 (4.35) (2018) 700-704 International Journal of Engineering & Technology Website: www.sciencepubco.com/index.php/IJET Research paper Utilization of Carbide Lime Waste as Base Catalyst for Biodiesel Production Koguleshun Subramaniam 1 , Sasidevan Munusamy 2 , Fei-ling Pua 3 *, Mohd Aizat Mohd Nasir 5 , Rohaya Othman 6 , Sharifah Nabihah Syed Jaafar 6 1 Department of Mechanical Engineering, UNITEN, 43000 Kajang, Selangor, Malaysia. 2 Institute of Sustainable Engineering (ISE), UNITEN, 43000 Kajang, Selangor, Malaysia. 3 Mineral Research Centre, Rock Based Technology Section, Department of Mineral and Geoscience Malaysia, Perak, 31400 Ipoh, Perak, Malaysia. 4 Bioresources and Biorefinery Laboratory, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia. *Corresponding author E-mail: gracepua@uniten.edu.my Abstract Calcium rich solid base catalyst was synthesized from local waste carbide lime and its catalytic performance was evaluated via biodiesel production. Carbide lime waste was used to produce CLW-I and CLW-II solid base catalyst using different preparation methods. Charac- terization including base strength analysis, scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) were investigated. Catalytic strength was examined by deploying the solid base catalysts for transesterification reac- tion of palm oil. Fourier Transform Infra-red (FTIR) was used to analyze the presence of ester group in biodiesel. The yield of biodiesel conversion was calculated based on the mass of biodiesel and glycerol. The highest biodiesel conversion rate of 75.30% was achieved by CLW-I solid base catalyst at 9% loading. The good catalytic performance of carbide lime waste derived solid base catalysts proves that it has high potential to replace the usage of conventional catalyst in the biodiesel industry. Keywords: Catalyst; Carbide lime waste; Base catalyst; Transesterification; Biodiesel 1. Introduction Rapidly rising population growth and the increasing demand for energy has awakened the need to prepare an alternative energy resource to tackle these challenges. Alternative energy resource in the form of renewable energy is seen to be the best fit for this issue for a number of reasons. The major reason being that this particular type of energy resource is capable of meeting existing and future energy demands and also being environment-friendly at the same time. Renewable energy is replenishable, hence it can be used for a long period of time without worrying that it might run out anytime soon. Existing energy resources are mainly fossil fuel extracts such as coal, petroleum, and natural gas. Though these resources are still available for use, its impact on the environment rings a bell and calls for attention. Environmental pollutions caused by non-renewable energy are getting greater each day, hence it is a wise move to shift towards a cleaner energy option to save what is left. Renewable energy can be classified into few types that include solar, wind, tidal, geothermal, hydropower, and biomass [1]. Petroleum diesel produces greenhouse gases (GHG) and air- contaminants such as CO 2 , SO x , NO x , and CO, increasing the at- mospheric pollution rate [2]. Meanwhile, biodiesel generates much lesser GHGs and air containments through combustion, minimizing the atmospheric pollution rate. Moreover, feedstocks used for biodiesel production is of organic origin and it is readily available in large quantities due to the large scale food industry that will constantly produce feedstocks such as waste cooking oil and animal fat. Hence, continuous supply of feedstock for bio- diesel production is not something to be worried about as the food industry is not at the risk of shutting down anytime soon. Besides, biodiesel can be used in existing diesel engines without any modi- fications [3]. This puts biodiesel as a cleaner and considerable option to replace other traditional fuels. The transportation sector, private cars, buses, trucks, and production industries are using petroleum diesel extensively. Fossil fuel generates 80 % of the world’s energy demand [4]. Therefore, replacing petroleum diesel with biodiesel is an ideal way of reducing the huge dependence on non-renewable resources. Biodiesel is seen as a substitute to conventional petroleum diesel because it is less harmful to the environment and can be made available for a long time with proper production planning and execution. Biodiesel can be defined as a mixture of fatty acid alkyl esters (FAME) produced by transesterification or methanolysis reaction. In transesterification reaction, triglyceride reacts with alcohol in the presence of a catalyst. Biodiesel will be produced as the main product and glycerol as side product. Although there are other conventional methods of producing biodiesel, transesterification is favored among others as it is easy, can be conducted at normal conditions, and provides the best biodiesel yield and quality of fuel. The reaction is usually catalyzed by an acid or base catalyst [2] [5]. The biodiesel industry is facing prob- lems with the existing homogenous catalysts as it’s not easily separable from the end-product of transesterification. The separa- tion is tedious and results in higher biodiesel production costs. Meanwhile, heterogeneous catalysts have more advantages i.e. non-corrosive, present lesser separation problems. Heterogeneous