Figure 5.

Comparison of a factorial design experiment (a) and the one-factor-at-a-time (OFAT) approach (b) for the maximization of the product yield by optimizing two representative process factors: pH and temperature. a: The factorial experimental design allows the investigation of all possible combinations of the two factors on different levels considering potential interdependencies between the factors within the design-space. Optimum conditions for both factors that give maximum yield can be determined. b: In the OFAT approach, both factors are investigated sequentially (1st, 2nd) neglecting factor interactions, leading to the loss of conclusive information and thereby missing the true maximum.