*3.5. Optimization of the Process Variables for Bio-Jet Fuel*

To obtain the highest value of bio-jet fuel yield, the optimization of the studied variables was carried out using RSM and ANN-ACO. In the case of RSM, the in-build optimization method in the Design Expert software was used for the optimisation study. On the other hand, the ANN models acted as the fitness functions when combined with ACO in the case of optimization using the ANN-ACO method. Table 7 shows the optimum values expected by each system. For each model bio-jet fuel validated by triplicate experiments in the laboratory, the expected optimal condition and the average bio-jet fuel yields were reported (Table 7). From the result, it was observed that RSM predicted 72.49% of bio-fuel jet yield. While for ANN-ACO, the predicted yield was 74.45% with process variables (9.25:1 ethanol oil molar ratio, 12.66 min reaction time and 163.69% microwave power) was higher than most RSM values.

**Table 7.** Optimization of RSM and ANN-ACO.

