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Traditional lubricants are commonly mineral oil-based, which could do direct harm to environment because of its poor biodegradability. With the growing awareness towards environmental protection, vegetable oil-based lubricants have a wide development prospect because of its outstanding biodegradability, excellent lubricating and viscosity-temperature property. But its poor oxidation stability, hydrolytic stability and low-temperature performance limit its use as lube base oil. In this paper, Jatropha curcas L. oil (JO)-based biodegradable lube base oil was prepared through the transesterification of JO and TMP with Novozym 435 as catalyst. Finally, JO, modified JO and base oil were mixed together to discuss the effect of the additive amount on the viscosity, acid value, solidifying point, oxidation stability and biodegradability of base oil.In the preparation of JO-based biodegradable lube base oil, the effect of different alcohols, reaction temperature, oil-alcohol molar ratio, reaction time and lipase’s amount on the basic physicochemical properties of products had been discussed. The results showed that modified JO (TMP ester), which had better oxidation stability, higherⅥ, lower acid value than JO, could be obtained under optimum reaction conditions (TMP,65℃, oil-alcohol molar ratio as 1:3,21h, Novozym 435 as 7%). So it’s proven that the direct transesterification of JO and TMP was an effective way to improve JO’s oxidation stability.Then, JO, JME (modified by methanol), TMPE (modified by TMP) and base oil (BO) were mixed together to discuss the effect of the additive amount on the viscosity, acid value, solidifying point, oxidation stability of base oil. A conclusion can be drawn that adding 10% TMPE to base oil was the best:solidifying point dropped down to -24℃without significant change of the other three characteristics.The oxidative induction time (OIT) of BO, JO, JME, TMPE and mixed oils were measured by RBOT. It turned out that both modified methods could improve JO’s oxidation stability (TTMPE=TJME>TJO) and mixed oils (BO added by JME/TMPE) could achieve better oxidation stability than those added JO to BO directly (TTMPE10> TJME10>TJO10).It showed that both methods especially modified by TMP could improve JO’s oxidation stability effectively. Finally, the biodegradability of BO, JO, JME, TMPE and mixed oils were evaluated by the improved CEC-L-33-A-93 method. It came to a conclusion that the 21d biodegradation rate of BO was 25.93% but JO was 94.95%, which proved that JO’s biodegradability was much better than BO; both modified methods had little effect on JO’s biodegradability, moreover, BO’s biodegradability had a distinct increase by adding 10% JO/JME/TMPE.In this research, biodegradable lube base oil, which had better oxidation stability, lower acid value and similar viscosity, was prepared through the transesterification of JO and TMP with Novozym 435 as catalyst. The results showed adding 10% TMPE to base oil could remarkably improve its low-temperature performance and biodegradability.
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