International Journal of Emerging Engineering Research and Technology Volume 7, Issue 9, 2019, PP 7-18 ISSN 2349-4395 (Print) & ISSN 2349-4409 (Online) Optimization, Kinetics and Thermodynamics Study of Transesterification of Neem Oil Using Heterogeneous Catalyst Derived from Waste of Goat Bones Wisdom ChukwuemekeUlakpa1*, CallistusNonso Ude2, Ruth.O.Ulakpa3 1Chukwuemeka Odumegwu Ojukwu University, Department of Chemical Engineering, P.M.B 02, Uli, Anambra State, Nigeria 2Engineering Research Development and Production Department, Projects Development Institute (PRODA), Enugu State, Nigeria 3Enugu State University of Science and Technology, Department Environmental Management, P.M.B. 01660, Enugu State., Nigeria *Corresponding Author: Wisdom Chukwuemeke Ulakpa, Chukwuemeka Odumegwu Ojukwu University, Department of Chemical Engineering, P.M.B 02, Uli, Anambra State, Nigeria, Email: [email protected] ABSTRACT In this study, calcium oxide (CaO) derived from waste bone (from goat) was used as catalyst for the transesterification of neem seed oil (NSO). The catalyst was characterized using scanning electron microscope (SEM).The transesterification was optimized using response surface methodology (RSM). Under the optimal conditions of methanol to oil molar ratio of 8:1, catalyst concentration of 4.0wt %, reaction temperature of 550C, reaction time of 4hr and agitation speed of 400rpm, 92.0% biodiesel was achieved. The reaction kinetics conforms to a pseudo-second order rate law with reaction rate constants of 1.96E-5, 2.17E-5 and 5.18E-5, at 45, 50 and 550C, respectively. Activation energy (EA) for the reaction was 90.98 kJ/mol and pre-exponential factor of1.46E10dm3mol-1min-1.Thermodynamic parameters calculated for the reaction show the enthalpy and entropy for the process to be 90.98 kJ mol-1 and 0.195 kJ mol-1 respectively. The Gibbs free energy was calculated to be -28.63, 28.84 and 26.95 kJ mol-1 at 45, 50 and 55oC, respectively. Keywords: Transesterification, Kinetics, Catalyst, Optimization, Neemseed oil, Thermodynamics. conventional diesel fuel (Sanjay, 2013; INTRODUCTION Demirba2003; Kaya et al., 2009; Hetsi et al., Fast depletion of world’s petroleum reserves 2009). Biodiesel is the mixture of mono alkyl and increasing ecological concerns has created a esters that can be continuously derived from great demand for environmentally benign vegetable oils or animal fats and therefore it is renewable energy resources (Ashish et al., termed as renewable energy (Lin et al., 2006). 2010). There is an increasing worldwide concern Several studies have shown that biodiesel is a for environmental protection and for the better fuel than fossil based diesel in terms of conservation of non-renewable natural resources. engine performance, emissions reduction, For this reason the possibility of developing lubricity, and environmental benefits (Canakci alternative energy source to replace traditional et.al., 1997; Peterson et al.,1997). fossil fuels has been receiving a large interest in the last few decades (Vicente et al., 1998). Different types of catalysts such as base, acid or lipase are used in transesterification for Biodiesel is considered as a possible alternative biodiesel synthesis but the base-catalyzed and future fuel for diesel engine due to the reaction is the most common in the industry due predicted shortage of fossil fuels and increase in to easier, faster and cheaper processing (Hassan the price of the petroleum. et al., 2013). The conventional catalysts used for It is biodegradable, renewable, non-toxic, transesterification are homogeneous and environmentally-friendly, and has high flash heterogeneous catalysts. The biodiesel industry point, better lubrication, high cetane number and is dominated by application of homogeneous has quite resemblance in regard with physical catalysts (such as KOH, NaOH and CH3ONa) and chemical characteristics with that of because of their easy usage and short time International Journal of Emerging Engineering Research and Technology V7 ● I9 ● 2019 7 Optimization, Kinetics and Thermodynamics Study of Transesterification of Neem Oil Using Heterogeneous Catalyst Derived from Waste of Goat Bones required for conversion of triglycerides to animal fats and micro algal oil. In the midst of biodiesel (Demirbas 2008; Sharmaet al., 2011). them, vegetable oil is currently being used as a sustainable commercial feedstock. There are However, the use of homogeneous catalysts number of edible oil available in market i.e. requires neutralization and separation from the Sunflower oil, Soyabean oil, cotton seed oil, final reaction products leading to a series of coconut oil, ground nut oil etc. from which environmental concerns such as production of preparation of biodiesel can be achieved. But waste water and corrosion problems (Georgogianni use of edible oil is generally used for cooking et al., 2009). purpose. Similarly if edible oil is used for Among heterogeneous catalysts which have biodiesel production it can cause the shortage of been researched, calcium oxide a solid base oil for cooking and the cost of oil may go high catalyst shows high potential/promising result in (Hanumanth et al., 2012). However, it may transesterification process with oil conversion of cause some problems such as the competition more than 95% (Liu et al., 2008). This catalyst with the edible oil market, which increases both is low cost, low methanol solubility, non-corrosive, the cost of edible oils and biodiesel. In order to environmental friendly and able to be reused for overcome these disadvantages, many researchers several times (Boey et al., 2011).There are are interested in non-edible oils which are not various processes/techniques that have been suitable for human consumption because of the adopted in production of biodiesel from vegetable presence of some toxic components in the oils oils and animal fats namely: dilution, micro- (Patni Neha et al., 2013). emulsification, pyrolysis and transesterification The various non-edible oil which can be used process/ technique (Demirbas et al., 2009; for the preparation of biodiesel are jatropha Aderemi et al., 2010; Leng et al., 1999; Jabalu et al., 2009). Among these methods, transesterification oil(J. curcas), karanja oil(P. pinnata), Beef is the key and foremost important process to tallow oil, used frying oil, other waste oil and produce the cleaner and environmentally safe fats, Pongamia pinnate oil, Kokum oil, Mahua fuel (Younis et al., 2009; Atlanatho et. al., oil (M. indica), Simarouba oil, willed apricot oil, 2004). Biodiesel is produced through a chemical Jojoba oil, Tobacco seed oil (N. tabacum L.), process known as transesterification of different rice bran, mahua rubber plant (H. Brasiliensis), vegetable oil or animal fat with a short chain castor oil, linseed oil, and microalgae, Kusum alcohol, in which one mole of glyceride reacts oil, Neem oil (A. indica) and sal oil but the use with three moles of alcohol in the presence of of these oils as a feed stock for production of appropriate amount of catalyst to form mono biodiesel varies as per their availability in methyl ester and glycerol (Balat et al.,2010; different parts of the world. Demirbas 2009; Ghanei et al.,2011;Helwani et Different researchers synthesized and used al.,2009; Moradi et al.,2012).Transesterification different kinds of solid wastes based catalysts of vegetable oils with low molecular weight (such as mollusk shells, eggshells, calcined fish simple alcohols (methanol, ethanol, propanol, scale, sheep bone, calcined waste bone etc.) in butanol and amyl alcohol) has been established order to produce cost effective catalysts and as the best option to reduce the high viscosity, biodiesel (Viriya-Empikul et al., 2010; Jiang et low volatility, heavy engine deposits and toxic al; 2015). Obadiah et al. (2012) worked on the substance formation associated with the direct biodiesel production from palm oil using use of vegetable oils (edible, non-edible, animal calcined waste animal bone as catalyst. The fats and used cooking oil) Schwab et.al.,(1987); biodiesel yield was 96.78 % under optimal Tesser et.al., (2005). reaction conditions of 20 wt% of catalysts, 1:18 The most common alcohols widely used are oil to methanol ratio, and 200 rpm of stirring of methyl alcohol and ethyl alcohol. Methanol, reactants and at a temperature of 650C. found frequent application in the commercial Among these solid wastes, animal bone is one of uses because of its low cost and its physical and the best solid wastes that are easily and chemical advantages (Demirbas, 2005). Another abundantly available all over the world. advantage of using methanol is the separation of Although, the waste bone derived catalysts have glycerine, which can be obtained through simple shown a reasonable performance and constancy decantation (Nagi et. al., 2008). in the reaction, however these catalysts are The current feed stocks for production of required in high amount, high methanol/oil biodiesel or mono-alkyl ester are vegetable oil, molar ratio with longer time for the reaction to 8 International Journal of Emerging Engineering Research and Technology V7 ● I9 ● 2019 Optimization, Kinetics and Thermodynamics Study of Transesterification of Neem Oil Using Heterogeneous Catalyst Derived from Waste of Goat Bones occur. All these disadvantages make waste bone Catalyst Preparation/Activation derived catalysts practically and economically The catalyst (waste animal bones) from goats unsuitable. To overcome these difficulties, it was sourced