双功能气凝胶吸附-降解协同处理染料废水_王文涛.pdf

研究论文 Article *E-mail:; Received January 12,2023;published February 27,2023.Supporting information for this article is available free of charge via the Internet at http:/sioc-.Project supported by the National Natural Science Foundation of China(Nos.22178324,21908201),Zhejiang Provincial Natural Science Foundation(No.LY21B060011)and China Postdoctoral Science Foundation(No.2020M671793).国家自然科学基金(Nos.22178324,21908201)、浙江省自然科学基金(No.LY21B060011)和中国博士后科学基金(No.2020M671793)资助.222 http:/sioc- 2023 Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences Acta Chim.Sinica 2023,81,222230 化 学 学 报 化 学 学 报 ACTA CHIMICA SINICA 双功能气凝胶吸附-降解协同处理染料废水 王文涛*,a 赖欣婷a 闫士全a 朱雷a 姚玉元a 丁黎明*,b(a浙江理工大学 材料科学与工程学院 杭州 310018)(b国家纳米科学中心 北京 100190)摘要摘要 针对吸附法处理染料废水易产生二次污染和基于过一硫酸氢盐(PMS)的高级氧化技术降解有机污染物易受水体复杂成分影响的问题,设计构筑具有吸附和活化 PMS 功能的铁掺杂纤维素纳米纤维/还原氧化石墨烯气凝胶(CNFs/RGO/Fe)用于吸附-降解协同处理染料废水.CNFs/RGO/Fe 对阳离子染料具有良好的选择性吸附功能,其对亚甲基蓝(MB)、罗丹明 B(RhB)和结晶紫(CV)的最大吸附容量分别高达 655.1 mg/g、696.5 mg/g 和 962.1 mg/g,吸附过程符合准二级动力学模型和Langmuir等温模型.将吸附染料的CNFs/RGO/Fe置于PMS溶液中,可以促进PMS活化产生大量OH,实现对吸附质的降解和气凝胶的再生.经 5 次吸附-降解循环后,CNFs/RGO/Fe 对染料去除率仍保持在 75%以上,表现出良好的重复使用性.本研究有望为去除复杂水体中有机污染物提供新思路.关键词关键词 吸附;降解;气凝胶;高级氧化技术;染料废水 Synergistic Treatment of Dye Wastewater by the Adsorption-Degradation of a Synergistic Treatment of Dye Wastewater by the Adsorption-Degradation of a Bifunctional Aerogel Bifunctional Aerogel Wang,Wentao*,a Lai,Xintinga Yan,Shiquana Zhu,Leia Yao,Yuyuana Ding,Liming*,b(a School of Materials Science and Engineering,Zhejiang Sci-Tech University,Hangzhou 310018,China)(b National Center for Nanoscience and Technology,Beijing 100190,China)Abstract Dye wastewater with high toxicity and poor biodegradability poses a considerable threat to human health and the ecosystem.Although the adsorption effectively removes organic pollutants from wastewater,the pollutants are merely trans-ferred from liquid phase to solid adsorbents.Destroying the adsorbed pollutants and regenerating adsorbents require addi-tional treatments,which may cause secondary harm to the environment.In addition to the removal of organic pollutants by adsorption,the pollutants can be oxidatively degraded by oxidative radicals that are generated in peroxymonosulfate(PMS)-based advanced oxidation technology.However,the degradation efficiency of organic pollutants treated by advanced oxidation technology may be affected by complex components of dye wastewater.Herein,Fe-doped cellulose nano-fiber/reduced graphene oxide aerogel(CNFs/RGO/Fe)was prepared and served as both adsorbent and catalyst in advanced oxidation process for dyes wastewater treatment.The morphology and chemical composition of the composite aerogel were characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).It was proved that CNFs/RGO/Fe possessed layered porous structures,which are beneficial for the transport,diffu-sion,and adsorption of pollutants.The uniform loading of Fe0 and Fe3O4 particles on the aerogel skeleton contributed to the efficient activation of PMS.The results of the adsorption experiment showed that the CNFs/RGO/Fe exhibited excellent se-lective adsorption for cationic dyes.The maximum adsorption capacity of methylene blue(MB),rhodamine B(RhB),and crystal violet(CV)on CNFs/RGO/Fe were 655.1 mg/g,696.5 mg/g,and 962.1 mg/g,respectively.The pseudo-second-order kinetic model and Langmuir isothermal model fitted well with the adsorption process of CNFs/RGO/Fe for cationic dyes.After adsorption,the CNFs/RGO/Fe was immersed in PMS solution separately to study the degradation performance for the adsorbate.The results showed that CNFs/RGO/Fe could promote the activation of PMS to generate a large amount of OH,leading to the degradation of adsorbate and the regeneration of adsorbent.In addition,the synergistic adsorption-degradation process established by CNFs/RGO/Fe achieved over 75%removal of dyes even after 5 cycles,indicating CNFs/RGO/Fe had good repeatability.The study on the synergistic treatment of dye wastewater by adsorption-degradation is expected to provide a new perspective for the removal of organic pollutants in complex water.Keywords adsorption;degradation;aerogel;advanced oxidation technology;dye wastewater DOI:10.6023/A23010009 化化 学学 学学 报报 研究论文 Acta Chim.Sinica 2023,81,222230 2023 Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences http:/sioc- 223 1 引言 染料废水通常具有毒性大、色度高、降解难等特点,是难处理的工业废水1-3,开发高效、环保的染料废水处理方法是水环境治理领域的重要研究方向.在众多染料废水处理方法中,吸附法因操作简单、成本低及应用范围广等优点被认为是最经济有效的方法之一4-7.石墨烯气凝胶,具有大的比表面积、丰富的活性位点及易分离回收的特点8-9,在吸附处理染料废水方面表现出巨大的应用潜力.但仅由石墨烯组装而成的气凝胶力学强度较差,且石墨烯片层间易过度堆叠导致比表面积下 降10-11,从而影响吸附性能.针对上述问题,研究者们开发了不同改性石墨烯气凝胶用于染料吸附,如制备再生纤维素/氧化石墨烯复合气凝胶12、聚乙烯醇/氧化石墨烯复合气凝胶13等增强气凝胶力学强度的同时减少石墨烯片层间的堆叠,从而有效提高处理染料废水的性能.然而,以上改性石墨烯气凝胶用于染料废水处理仅是将污染物从液相转移至固相,去除被吸附污染物和吸附剂再生仍需进一步处理,容易造成二次污染.基于过一硫酸氢盐(PMS)的高级氧化技术可产生强氧化性自由基(SO4、OH 等)使难降解有机污染物氧化分解甚至完全矿化,是一种新型染料废水处理技 术14-16.该技术的关键是活化 PMS 使其产生强氧化性自由基.在众多活化 PMS 的方法中,非均相铁基催化剂,具有催化活性高、pH 适用范围广及重复使用性能好等优势17-18,是活化 PMS 的理想途径.Zhang 等19开发