Synthesis of Bio lubricant from Neem Seed (Azidirachta indica) Oil for Agricultural Machines.

Abstract

In this study, Neem seed was used as a feedstock for the extraction of oil, production of biodiesel and biolubricant production. The oil was extracted by solvent extraction method using N-hexane as solvent. The oil was analyzed for chemical and physical properties such as density, pour point, acid value, free fatty acid (FFA), smoke point, flash point, specific gravity, saponification value, peroxide value, iodine value as well as viscosities at 350C and 400C. The method of transesterification was used in the production of the biodiesel from the extracted oil using potassium hydroxide as catalyst. This was characterised using the American standard Test Methods (ASTM) and parameters such as viscosity, specific gravity, cloud point, pour point, smoke point, flash point, fire point, acid value and free faty acid were analysed. The method employed for the production of bio lubricant involved two stages transesterification process, the first stage produced methyl ester of the oil and in the second stage; the methyl ester was transesterified with ethylene glycol to produce the bio lubricant. The result of the analysis of the extracted neem oil reveals that it has a very high FFA (3.7%). Reduction was achieved by esterification with methanol to 0.7%. Major lubricating properties of the product such as pour point, viscosity index and viscosities at 40°C and at 100°C were analyzed and found to have values of -5°C, 185.64, 38.7cSt, and 14.3cSt respectively. It was found that the bio lubricant produced is comparable to the ISO VG-32 standards, hence, the synthesized bio lubricant can satisfactorily serve as substitute for petroleum-based lubricants for industrial and agricultural machines.