Abstract:
Due to the increasing demand of conventional energy source, depletion of conventional energy source emphasized the world’s automotive industries to shift towards a renewable source of energy. The purpose of this study is to produce the TMP (Trimethylolpropane) based bio-lubricant (renewable energy source) from different feedstock of vegetable oils and analyze their physicochemical properties when nanoparticles were added to these bio-lubricants. In this work, cottonseed oil, rattan jot oil and waste cooking oil was converted to TMP based bio-lubricant by a two-step based catalyzed esterification. In first step biodiesel was produced from raw vegetable oil and in the second step TMP based bio-lubricant was produced in the presence of sodium methoxide as catalyst. Two types of nanoparticles (MoS2 and ZnO) were used to make the nanolubricants, and their effects on physicochemical properties of lubricants are investigated at one weight percent concentration of nanoparticles. The produced TMP based bio-lubricants from three feedstock oils have a viscosity index of 194,167 and 118 while flash points of produced bio-lubricants were found 175oC, 155oC and 150oC. Other physicochemical properties were also comparable with the commercial lubricants but there is a need to further increase the viscosity of bio-lubricants. With the addition of nanoparticles, the flash point, pour point, density and TAN increases while the viscosity of the nanolubricants was decreased. The addition of nanoparticles reduced the viscosity of two oil samples (CSO and WCO) significantly. A viscosity reduction of 30–40% was recorded for each type of nanoparticle. In case of RJO there was an increase in viscosity by 20-25%. Bio-lubricants fail to give positive results with ZnO nanoparticles while PAO show synergetic behaviors with ZnO nanoparticles. There is a need to check the nano lubricant’s tribological behavior that contains more than one nanoparticles. Due to the non-toxic nature of these lubricants, they can be used as primary lubricant in pharmaceutical industries. These can also be used in blended form with synthetic lubricants in IC engines. The viscosity of the bio-lubricant can also be improved by lowering the vacuum pump pressure. However, more work on improving the physicochemical properties of bio-lubricants is required before they can completely replace mineral oil-based lubricants.
