Study On Photocatalytic Properties And Chemical States Of Mg Species Of Mg Doped Aluminophosphate Molecular Sieves

Different MgSO₄ doped aluminophosphate molecular sieves were prepared by hydrothermal synthesis starting from phosphoric acid and pseudo-boehmite as the source of phosphorus and aluminum, using triethylamine as organic template, and in-situ mixed with magnesium sulfate. Then, it was crystallized at a certain temperature and time. The products were characterized by XRD, SEM, XRF, XPS, FT-IR, TG-DSC, UV-Vis-DRS, BET, its photocatalytic activities was evaluated by the photodegradation of orange II and eosin B under ultraviolet irradiation and the photodegradation of methylene blue and eosin B under visible light. Its photocatalytic activities were evaluated by the photodegradation of methylene blue under visible light with different Mg, and the using cycle of MgAPO-5 molecular sieves were discussed. The primary results showed that, the samples had the same structure of aluminophosphate molecular sieves, it also revealed well photocatalytic activity of samples on orange II, eosin B and methylene blue under ultraviolet irradiation and visible light. The decolourizing rate of the orange II solution was 59.6 % and the eosin B was 97.2 % under UV illumination, and the decolourizing rate of the methylene blue solution was 88.5 % and the the eosin B was 97.2 % under visible light. And the same time, when the doped Mg amount is 1.84 %, the decolourizing rate is the lowest, only 64.4 %, but when the doped Mg amount is 1.01 %, the decolourizing rate is the highest, up to 88.5 %. It also revealed well the cycle use of MgAPO-5, and the maintain basic activity was not declining after recycling 6 times.