Photo-degradation of the methyl blue: Optimization through response surface methodology using rotatable center composite design

Abstract

Advanced oxidation processes (AOPs) generate in situ active hydroxyl radicals which allowed the destruction of polluting agents through mineralization. The suitable experimental design allows adjustment of factor levels to obtain an optimal response in experimental analysis. Rotatable Center Composite design and multivariate analysis were used for the optimization of the removal of methyl blue from aqueous solution, using UV (254 nm) radiation source and hydrogen peroxide as an oxidant. A factorial design (2 n ) with repeated central and axial points was used to obtain the best experimental condition to efficiently remove the dye from aqueous solution and initial dye concentration, 50-150 ppm and hydrogen peroxide 0.05-5.95 % was used as experimental variables. At optimum level up to 96.5% dye removal was recorded. Dye degradation followed the first order kinetics and dissolved oxygen and pH of the dye aqueous solution were found strongly correlated with the dye degradation.

Spin Coating Immobilisation of C-N-TiO2 Co-Doped Nano Catalyst on Glass and Application for Photocatalysis or as Electron Transporting Layer for Perovskite Solar Cells

“…AOPs are based on the production of non-selective hydroxyl radicals (OH•) [7]. After fluorine (3.06 V), the OH• radicals are considered to be the most powerful oxidant species (2.8 V) that can directly or indirectly mineralize these pollutants into dissolved CO 2 , H 2 O, and harmless end-products [8][9][10].…”

Anticorrosion Coated Stainless Steel as Durable Support for C-N-TiO2 Photo Catalyst Layer

“…Advanced oxidation processes (AOPs) are considered as robust techniques capable of degrading organic contaminants in water and wastewater, converting them into harmless substances without any post-treatment processes needed [17][18][19][20][21][22][23][24]. AOPs are based on the generation of the hydroxyl radical, a strong oxidation agent that can completely degrade organic contaminants into forms such as CO 2 , water and simple salts [4,20,22,24,25]. AOPs induced by photo catalysis under solar and UV light are promising techniques for the removal of POPs and deactivation of pathogenic micro-organisms from water sources [26,27].…”