MnAPo-5分子筛光催化降解亚甲基蓝

以磷酸为磷源、拟薄水铝石为铝源、三乙胺为模板剂,采用水热法原位掺杂硫酸锰合成了锰掺杂的 MnAPO-5分子筛,通过 X 射线粉末衍射、X 射线荧光光谱、傅里叶变换红外光谱、紫外-可见漫反射光谱、热重分析、扫描电子显微镜、低温 N_2吸附-脱附等方法对 MnAPO-5分子筛的结构和理化性能进行表征,并以亚甲基蓝为目标降解物在可见光下评价了 MnAPO-5分子筛的光催化性能。结果表明,MnAPO-5分子筛具有 AlPO_4-5分子筛结构,结晶度高,掺杂的 Mn 进入磷铝分子筛骨架中;MnAPO-5分子筛为微孔的骨架结构;该分子筛具有良好的光催化性能,在80 mL 质量浓度为4 mg/L 的亚甲基蓝溶液中加入0.1 g MnAPO-5分子筛催化剂,辐照300 min 时,亚甲基蓝的降解率可达88.0%。

Photocatalytic Degradation of Methylene Blue over MnAPO-5 Molecular Sieve

Manganese doped aluminophosphate(MnAPO-5)molecular sieves were prepared by hydrothermal synthesis starting from phosphoric acid and pseudo-boehmite as sources of phosphorus and aluminum.Manganese sulfate was added directly during synthesis.Triethylamine was used as organic template.The structure of MnAPO-5 was characterized by XRD,XRF,FTIR,UV-Vis DRS, TG,SEM and N_2 adsorption-desorption isotherms.The photocatalytic activities of MnAPO-5 were evaluated by photodegradation of methylene blue under visible light.MnAPO-5 keeps the same structure as AIPO4-5.Its crystallinity is high.The doped manganese enters into framework of the molecular sieve.The nitrogen adsorption isotherms of MnAPO-5 are typical type Ⅰ isotherms of IUPAC classification of adsorption isotherms,which indicates microporous structure of the molecular sieve.Under visible-light irradiation of 300 min,the methylene blue decolourizing rate goes up to 88.0% by adding 0.1 g photocatalyst to 80 mL methylene blue solution with concentration of 4 mg/L.