Simultaneous Photocatalytic Reduction of Cr(VI) and Oxidation of Benzoic Acid in Aqueous N-F-Codoped TiO₂ Suspensions: Optimization and Modeling Using the Response Surface Methodology

Figure 8

3D response surface plots for the % BA degradation; (a) as a function of N-F-TiO₂ concentration and Cr(VI)/BA ratio; (b) as a function of pH and N-F-TiO₂ concentration.

(a)

(b)