天冬氨酸-β-环糊精强化TiO_2-石墨烯光催化降解酸性红R的研究

Enhanced TiO_2-graphene photocatalytic degradation of acid red R by aspartic acid-β-cyclodextrin JIANG Yao,LI

利用Hummers氧化还原法制备石墨烯(GR),并结合水热法制得TiO_2-GR,研究了天冬氨酸-β-环糊精(ACD)对TiO_2-GR光催化降解酸性红R的影响,同时考察了酸性红R初始浓度、pH和ACD浓度对光催化降解的影响。结果表明,ACD可以强化TiO_2-GR光催化降解酸性红R。pH为5、催化剂用量为1g/L、ACD质量浓度为100mg/L、氮气流量为6L/min时,60mg/L酸性红R经过20min光催化反应,降解率相比无ACD的情况可提高39百分点。酸性红R光催化降解率随酸性红R初始浓度升高而降低,随pH升高而降低。ACD在10~250mg/L时,随着ACD浓度的增加,光催化降解率先升高后逐渐降低。ACD可以加快TiO_2-GR光催化降解酸性红R的反应速率,ACD-TiO_2-GR体系中,酸性红R动力学常数为3.0×10-3 mg/(L·min),是TiO_2-GR体系的1.43倍。

In this study,the graphene（GR）was prepared by Hummers oxidation reduction method,and then TiO2-GR was prepared by hydrothermal method.The effects of aspartic acid-β-cyclodextrin（ACD）on the photocatalytic degradation of acid red R（ARR） were studied.Simultaneously,the effects of ARR initial concentration,pH and ACD concentration on photocatalytic degradation of ARR were investigated.The results showed that ACD could enhance the photocatalytic degradation of ARR.When pH=5,catalyst dosage was 1 g/L,ACD concentration was 100 mg/L and N2 flow rate was 6 L/min,after 20 min of ultraviolet irradiation,ACD had increased the photocatalytic degradation efficiency by about 39 percent points for 60 mg/L ARR,compared with the condition without ACD.The photocatalytic degradation efficiency of ARR decreased with the increase of ACD concentration and pH.The photocatalytic degradation efficiency of ARR first increased then decreased with the ACD concentration in the range of 10-250 mg/L.The photocatalytic degradation rate of ARR in the TiO2-GR system could be improved in the presence of ACD.The kinetic constant of ARR was 3.0 × 10-3 mg/（L·min）in the ACD-TiO2-GR system,which was 1.43 times of that in TiO2-GR system.