Formulation and Tribological property evaluation of rice bran oil based lubricating grease with sebacic acid as a complexing agent.

The consistency and tribological measurements of bio-grease, which consists of calcium 12-hydroxy stearic acid as a thickener with a complexing agent like sebacic acid dispersed in rice bran oil (RBO) at different formulation parameters, were examined. The calcium complex thickener was obtained by mixing calcium hydroxide to 12-hydroxy stearic acid (12 HSA) at a ratio of 1:1, and the concentration of sebacic acid added was varied from 1/3 to 1/6 of 12 HSA concentration. The weight percentage of thickener, saponification time, and holding time to dissolve sebacic acid spanned the ranges 5–11 wt.%, 1–2.5 h, and 10–25 min, respectively. The maximum temperature for formulating calcium complex grease was maintained at 160 °C. The present work experimentally investigated the effect of these grease formulation parameters on the formulated greases' consistency and tribological measurements as per ASTM standards. The experimental results obtained from the developed calcium complex greases (sixteen samples) have indicated that these formulation parameters' variation plays a vital role in the evaluated properties. [ABSTRACT FROM AUTHOR]