Co-SBA-15 for heterogeneous oxidation of phenol with sulfate radical for wastewater treatment

Mesoporous silica SBA-15 supported cobalt catalysts were prepared by co-condensation during SBA-15 synthesis, using three different Co(II) precursor salts, chloride (Cl), acetate (Ac) and nitrate (N). The physicochemical properties of the catalysts were characterized by several techniques, such as XRD, SEM (EDS), TEM, and FT-IR. It was found that Co3O4 was formed in SBA-15 and would effectively activate peroxymonosulfate to produce sulfate radicals for phenol oxidation in heterogeneous solutions. The Co precursors affected the physicochemical property, activity and stability of the catalysts. In heterogeneous reactions, the effects of catalyst loading, peroxymonosulfate concentration and reaction temperature on phenol degradation were investigated. The heterogeneous phenol degradation reactions followed zero order kinetics and the activation energies were 81.4, 67.4 and 67.4 kJ/mol for Co/SBA-15-Cl, Co/SBA-15-Ac, and Co/SBA-15-N, respectively.

Graphical abstract.Figure optionsDownload full-size imageDownload high-quality image (223 K)Download as PowerPoint slideHighlights► Co/SBA-15 exhibits high activity in heterogeneous activation of peroxymonosulfate. ► Phenol degradation can be achieved at 100% in short time with sulfated radical. ► Co/SBA-15-N exhibit high stability for phenol oxidation using sulfate radical.