Photocatalytic degradation of RhB,MG, MB,Roz.B, 3-BL and CI-50 by PW12-APTES@MCF as nanosized mesoporous photocatalyst

Surface of mesocellular silica foam (MCF) was modified by grafting 3-aminopropyltriethoxysilane (APTES) to have the positive charge, and thus, to provide sites for the immobilization of H₃PW₁₂O₄₀ (PW₁₂). This modified-nanosized mesoporous silica (PW₁₂-APTES@MCF) was characterized by FTIR, XRD, BET and TEM. The photoefficiency of this nanosized mesoporous toward photodegradation of six dye solutions rhodamine B, malachite green, methylene blue, rose bengal, solophenyl red (3-BL), yellow direct 50 (CI-50)] was investigated in a photocatalytic reactor using UV lamp as a light source. The effect of various experimental parameters on the degradation performance of the process was evaluated by examining catalyst dosage, initial dye concentration and pH of the dye solution in the presence of PW₁₂-APTES@MCF. The photocatalytic behaviors of the PW₁₂-APTES@MCF were also compared with two mesoporous silica-supported PW₁₂-APTES@SBA-15 and PW₁₂-APTES@KIT-6. It indicated that the PW₁₂-APTES@MCF had the highest photocatalytic efficiency among three mesoporous silica-supported PW₁₂-APTES. These photocatalysts can be reused several times although they get less active.