石墨相氮化碳协同UV-H_2O_2光催化降解亚甲基蓝

以三聚氰胺为前驱体,经热解—回流法制备了石墨相氮化碳(g-C3N4),采用XRD、FTIR、SEM、EDS、PL等技术对g-C_3N_4进行了表征。研究了g-C_3N_4在UV-H_2O_2体系中对废水中亚甲基蓝(MB)的光降解效果。实验结果表明,UV+g-C_3N_4催化剂+H_2O_2体系能协同降解MB,在初始MB质量浓度为20 mg/L、初始废水p H为5、废水体积为250 mL、g-C_3N_4加入量为0.10 g、H_2O_2浓度为0.4 mmol/L、反应温度为25℃的优化工艺条件下,紫外光照射70 min时MB脱色率达98.32%。g-C_3N_4催化剂具有较好的重复使用性能,使用5次后MB脱色率仍保持在95.10%。

Photocatalytic degradation of methylene blue by graphitic carbon nitride combined with UV-H2O2 system

The graphitic carbon nitride（g-C₃N₄）was synthesized by pyrolysis and reflux method using melamine as precursor and characterized by XRD,FTIR,SEM,EDS and PL. The photodegradation effect of methylene blue（MB）on g-C₃N₄ in UV-H₂O₂ system was investigated. The experimental results showed that MB could be degraded by UV+g-C₃N₄ photocatalyst+H₂O₂ system,and under the optimum process conditions of initial MB mass concentration 20 mg/L,initial wastewater pH 5,wastewater volume 250 mL,g-C₃N₄ amount 0.10 g,H₂O₂ concentration 0.4 mmol/L,reaction temperature 25 ℃ and radiation time 70 min,the decolorization rate of MB was 98.32%. In addition,the g-C₃N₄ photo-catalyst also showed good reusability and the decolorization rate of MB still remained 95.1% after 5 cycles.