Evaluation of reaction parameters of the phenol steam reforming over Ni/Co On ZrO₂ using the full factorial experimental design

Full factorial experimental design with 32 runs was used to investigate the significant and interaction variable of the reaction parameters on phenol steam reforming toward hydrogen production. Effects of selected factors on the phenol conversion (Y₁) and hydrogen yield (Y₂) were evaluated. These factors were as follows: (A) temperature (500 and 800 °C); (B) feed flow rate (0.16-0.46 mL/min); (C) catalyst weight (0.1-0.3 g); (D) Ni-Co ratio (0-1); and (E) phenol concentration in the feed (2-10 wt %). Ni and Co over ZrO₂ support for catalytic performance of phenol steam reforming (SRP) was prepared by the impregnation method. The result indicated that all the main independent variables had significant influence on the dependent variable of Y₁ and Y₂ with a range of 2.7%-96.8% and 21.4%-72.4%, respectively. Additionally, some interaction variables like AE, BE, CE, and DE have also influenced the Y₁ and Y₂ responses. This design showed that the best initial conditions that produced maximum Y₁ and Y₂ responses were at 800 °C, 0.16 mL/min feed flow rate, 0.3 g of catalyst, 0 ratio of Ni-Co (Co/ZrO₂), and 10 wt % of phenol in the feed, where the phenol conversion was predicted to be 94.98% and the hydrogen yield was predicted to be 67.4%. Within the limits the variables were examined, a regression model which well-fitted the experimental data was proposed. The regression model were reduced to simplify and to get the significant regression coefficient with p-value less than 0.05.