Table 2.

Optimization of the key reaction parameters^a.

Entryb	IL amountc (wt %)	Temp. (°C)	Vacuum degree (kPa)	Acid value (mg KOH/g)
1	10	160	50	123
2	10	170	50	106
3	10	180	50	92
4	10	190	50	88
5	10	200	50	86
6	0	190	50	148
7	5	190	50	117
8	15	190	50	73
9	20	190	50	69
10	15	190	0	101
11	15	190	10	63
12	15	190	30	52
13	15	190	50	44
14	15	190	70	43

^aStandard reaction conditions: ricinoleic acid (10 g, 30 mmol) and different amount of IL at a variety of temperature and vacuum degree; ^breaction time, 2 h (entries 1–9), 8 h (entries 10–14); ^cbased on ricinoleic acid.