化学混凝-TiO2/g-C3N5光催化降解处理印刷废水
Treatment of printing wastewater by chemical coagulation-TiO2/g-C3N5 photocatalytic degradation
马以宏 1陈兴涛 1汤雷2
作者信息
- 1. 中亿丰建设集团股份有限公司,江苏苏州 218131
- 2. 南京水利科学研究院材料结构研究所,江苏南京 210029
- 折叠
摘要
为了实现对高色度和高化学需氧量实际印刷废水的高效降解,采用混合法制备了TiO2/g-C3N5复合光催化剂.采用X射线衍射(XRD)、N2吸附-脱附、紫外可见漫反射光谱(UV-vis DRS)、稳态荧光光谱(PL)、瞬态光电流(TPC)和电化学交流阻抗(EIS)等表征技术对复合光催化剂的物相晶型、比表面积、光化学和电化学性能进行了全面的表征.TiO2与g-C3N5复合后形成异质结,提高了对可见光的吸收和转化能力,拓宽了光谱响应范围,有效抑制了光电子-空穴的复合,TiO2/g-C3N5比表面积达到了76.77 m2/g.以FeCl3和聚丙烯酰胺(PAM)为混凝剂和助凝剂对实际印刷废水进行预处理,实现了对印刷废水中悬浮物的去除.在TiO2/g-C3N5复合光催化剂投加量为0.8 g/L、光照时间为60 min、印刷废水pH为5的条件下光催化处理实际印刷废水,实际印刷废水的COD去除率和色度去除率分别为94.36%和96.82%.循环使用10次后TiO2/g-C3N5复合光催化剂对实际印刷废水的COD去除率和色度去除率分别为89.76%和90.34%,仍具有良好的处理效果.
Abstract
In order to achieve efficient degradation of actual printing wastewater with high chromaticity and high chemical oxygen demand,TiO2/g-C3N5 composite photocatalysts were prepared by a mixed method.The crystal phase,specific surface area,photochemical and electrochemical properties of the composite photocatalysts were characterized by X-ray diffraction(XRD),N2 adsorption-desorption,UV-vis diffuse reflectance spectroscopy(UV-vis DRS),steady-state fluorescence spec-troscopy(PL),transient photocurrent(TPC)and electrochemical impedance spectroscopy(EIS).The heterojunction was formed between TiO2 and g-C3N5,which improved the absorption and conversion ability of visible light,broadened the spec-tral response range,effectively inhibited the recombination of photoelectron-holes,and the specific surface area reached 76.77 m2/g.FeCl3 and polyacrylamide(PAM)were used as coagulants and coagulant aids to pretreat the actual printing wastewater,and the removal of suspended solids in printing wastewater was achieved.The actual printing wastewater was treated by photocatalysis under the conditions of TiO2/g-C3N5 composite photocatalyst dosage of 0.8 g/L,illumination for 60 min,and printing wastewater pH of 5,the COD removal rate and chroma removal rate of the actual printing wastewa-ter were 94.36%and 96.82%,respectively.After 10 times of recycling,the COD removal rate and chroma removal rate of the TiO2/g-C3N5 composite photocatalyst to the actual printing wastewater were 89.76%and 90.34%,respectively.It still showed good treatment effect.
关键词
TiO2/g-C3N5/光催化/印刷废水/化学混凝/复合光催化剂Key words
TiO2/g-C3N5/photocatalysis/printing wastewater/chemical coagulation/composite photocatalyst引用本文复制引用
基金项目
国家自然科学基金重点项目(51739008)
出版年
2024
NETL
NSTL
万方数据