Optimization Study in Biodiesel Production via Response Surface Methodology Using Dolomite as a Heterogeneous Catalyst

Table 3

Central composite design arrangement and results for transesterification of soybean oil using dolomite calcined at 800°C and a reaction time of 4 h.

Run	Independent variables			FAME yield (wt%)
	(°C)		(wt%)
1	55	6	0.6	85.5
2	65	6	0.6	89.9
3	55	15	0.6	93.6
4	65	15	0.6	96.1
5	55	6	2.0	92.6
6	65	6	2.0	91.6
7	55	15	2.0	93.2
8	65	15	2.0	94.3
9	60	10.5	0.6	93.7
10	60	10.5	2.0	95.0
11	60	15	1.3	94.4
12	60	6	1.3	89.3
13	65	10.5	1.3	94.6
14	55	10.5	1.3	95.6
15	60	10.5	1.3	97.3
16	60	10.5	1.3	96.5
17	60	10.5	1.3	97.1