1. No. of runs Xo X1 X2 X3 X4 Y1 Y2 Y3 Y4 Y5 Si2 1 +1 74 76 76.8 76.5 77
Table 3. Design of the experiment using coded value
No. of runs Xo X1 X2 X3 X4 Y1 Y2 Y3 Y4 Y5
Si2 1 +1 74 76
76.8
76.5 77
76.06
1.46 2 -1 65 66 64 68
66.5
65.9
2.3 3 70 69 71 72
2.5 4
74.5
73.7
0.95 5
2.25 6 73
75.5
73.5
1.75 7
71.5
72.2
71.54
1.30 8 62 60 61
62.2
3.2
∑ = 559.4
∑ Si2= 15.72
Where Y is the yield of biodiesel and is average value of Y. The sample variances were determined and tested for homogeneity on the basis of Cochran’s criterion. It was found that the sample variances are homogeneous for the significance level α = 0.05 and the number of degrees of freedom ν1 = 4 and ν2 = 8 and the error mean square was 1.96.
M. Rakib Uddin et al. Synthesis of Biodiesel from Waste Cooking Oil. Chemical Engineering and Science, 2013, Vol. 1, No. 2, doi: /ces-1-2-2
© The Author(s) Published by Science and Education Publishing.