Study on the Lubricating Properties of Castor (Ricinus communis) and Hydroxylated Rubber (Hevea brasiliensis) Seed Oil

Rubber seed oil (RSO) (Hevea brasiliensis) was extracted from rubber seeds by chemical means. The effect of temperature on the oil yield was investigated. The experiment suggested that the maximum yield of the oil occurs at 60 °C. This is a result of the proximity to the boiling point of n-hexane, which is about 68 °C. Epoxidized and hydroxylated RSOs were further synthesized by performic acid generated in situ by the reaction of formic acid with 30% hydrogen peroxide. The physiochemical properties of the epoxidized rubber seed oil (ERSO) and hydroxylated rubber seed oil (HRSO) were determined. A separate study was also carried out on castor seed oil (CSO). The improved products were characterized with respect to their configuration and properties. Spectroscopic analysis was carried out on the oil base stocks (RSO, CSO, ERSO, and HRSO). All of the experimental findings were compared with one another. The lubricating properties of CSO and HRSO are further studied as a result of their common hydroxyl nature to ascertain their suitability as a lubricant base. Both oils can be categorized as a nondrying oil with saponification values of 179.52 and 255.25 mgKOH/g, respectively, and as such possess advantageous properties for industrial application. When compared to one another, HRSO appears to be a more effective choice as a lubricant base. This is because of its higher viscosity index of 380.65. The outcomes of this study indicate that hydroxylated and epoxidized RSO with high oxirane content can be synthesized concurrently by one-pot multistep reactions.