杂多酸/Fe3O4磁性催化剂的制备及其对次甲基蓝溶液的降解

采用浸渍法将磷钨酸、磷钼酸和硅钨酸等杂多酸负载在Fe3O4磁性材料上，并将杂多酸/Fe3O4磁性材料作为光催化剂用于降解次甲基蓝溶液，考察了光源类型（紫外光与太阳光）、杂多酸种类及催化剂用量等对光催化降解效果的影响。结果表明，在250 W汞灯照射、次甲基蓝溶液浓度20 mg·L-1、降解体系pH=5.5、光催化剂用量30 mg和光催化120 min条件下，次甲基蓝降解率达85%，负载型杂多酸/Fe3O4磁性催化剂对次甲基蓝的降解效果明显优于相应单一的Fe3O4或杂多酸催化剂。

Preparation of heteropolyacid/Fe3 O4 magnetic catalyst and its degradation behaviors for methylene blue solution

Heteropoly acid/Fe3O4 magnetic materials were prepared by impregnation method to load differ- ent heteropoly acids on Fe3O4 magnetic materials and were used as the catalysts for photocatalytie degra- dation of methylene blue solution. The influence of type of light source （ ultraviolet and solar light）, spe- cies of heteropoly acid phosphotungstie acid （ HPW）, phosphomolybdic acid （ HPMo ） and silicotungstic acid （HSiW） ] and catalyst dosage on photocatalytic degradation effect of heteropoly acid/Fe3O4 magnetic materials was investigated. The results showed that the degradation rate of methylene blue reached 85% under the condition of 250 W mercury lamp irradiation, methylene blue initial concentration 20 mg pH value = 5.5 ,phosphotungstic acid/Fe3O4 photocatalyst dosage 30 mg, and photocatalytic time 120 min. The supported heteropoly aeid/Fe3O4 magnetic catalysts for methylene blue solution had better degradation effect than the single Fe3O4 or heteropolyacid catalyst.