吸附光催化协同提高有机物降解能力的研究
发布时间：2018-10-31 18:44
【摘要】：水污染作为环境污染的重要组成部分,对人们正常有序的生活与生产影响深远,有机废水中存在的大量难生物降解而且毒性很高的低浓度酚类有机污染物,严重影响人们的用水安全。针对单一光催氧化技术与吸附净化技术在去除水体中有机污染物中的弊端,首先通过化学还原法制备了石墨烯杂化氧化锌复合材料(ZnO/rGO),通过表征证明了ZnO与rGO之间存在相互作用,进而将石墨烯杂化氧化锌(Zn O/rGO)与大量石墨烯进行复合制备了具有宏观结构的石墨烯杂化氧化锌复合水凝胶(ZnO/rGO-rGH)。当ZnO/rGO中石墨烯的负载量为0.5 wt.%时,12 min内对苯酚的光降解效率高达98%,对比单体ZnO的光降解效率提升效果为2.5倍,石墨烯与Zn O形成的表面杂化结构有利于将光生电子快速转移到石墨烯上,成倍提高了ZnO的光催化活性。复合水凝胶吸附净化双酚A的过程符合准二级动力学方程模型,吸附等温线符合Langmuir等温线模型;ZnO/rGO-rGH吸附光催化协同作用对溶液中双酚A的净化效率高达100%,实现了对水体中酚类污染物的彻底净化,宏观水凝胶结构具有容易回收的特点,吸附光催化协同净化双酚A重复利用5次后的净化效率依然可以达到90%左右,可以有效解决粉体光催化难以回收的难题。通过研究ZnO/rGO-rGH吸附光催化协同作用对水体中不同初始浓度与不同流速下的双酚A净化作用,发现复合水凝胶可以在16 h内实现对流速0.48 m L/min,浓度为10 mg·L-1的双酚A彻底净化,而ZnO/rGO-rGH复合水凝胶通过吸附净化作用实现彻底净化双酚A只能维持4 h。说明复合水凝胶(ZnO/rGO-rGH)吸附光催化协同作用不仅可以有效去除静态下水体中的有机污染物,对流动态下水体中的有机污染物净化效果同样具有显著优势。
[Abstract]:As an important part of environmental pollution, water pollution has a profound impact on people's normal and orderly life and production. There are a large number of low concentration phenolic organic pollutants which are difficult to biodegrade and highly toxic in organic wastewater. Seriously affect people's water safety. In view of the disadvantages of single photocatalytic oxidation and adsorption purification in the removal of organic pollutants in water, graphene hybrid zinc oxide composites (ZnO/rGO) were prepared by chemical reduction method. The interaction between ZnO and rGO was proved by characterization, and then graphene hybrid zinc oxide (Zn O/rGO) was combined with a large amount of graphene to prepare graphene hybrid zinc oxide composite hydrogel (ZnO/rGO-rGH) with macrostructure. When the loading amount of graphene in ZnO/rGO was 0.5 wt.%, the photodegradation efficiency of phenol reached 98% in 12 min, and the photodegradation efficiency of monomeric ZnO was 2.5 times higher than that of monomer ZnO. The surface hybrid structure formed by graphene and Zn O is conducive to the rapid transfer of photogenerated electrons to graphene, which greatly improves the photocatalytic activity of ZnO. The process of adsorption and purification of bisphenol A by composite hydrogel accords with the quasi-second-order kinetic equation model, and the adsorption isotherm conforms to the Langmuir isotherm model. The synergistic effect of ZnO/rGO-rGH adsorption photocatalysis on the purification of bisphenol A in solution was as high as 100, which realized the thorough purification of phenolic pollutants in water, and the macroscopical hydrogel structure was easy to recover. The purification efficiency of bisphenol A can still reach 90% after 5 times of repeated use of adsorbent photocatalysis, which can effectively solve the difficult problem of photocatalytic recovery of powder. By studying the synergistic effect of ZnO/rGO-rGH adsorption photocatalysis on the purification of bisphenol A in water with different initial concentration and different flow rate, it was found that the combined hydrogel could achieve the optimal flow rate of 0.48 mL / min within 16 h. The concentration of 10 mg L ~ (-1) bisphenol A was completely purified, while that of ZnO/rGO-rGH compound hydrogel was only maintained for 4 h by adsorption and purification. The results show that the synergistic effect of photocatalytic adsorption of composite hydrogels (ZnO/rGO-rGH) not only can effectively remove organic pollutants in water under static conditions, but also has significant advantages under convection dynamic conditions.
【学位授予单位】：华北理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X52;O648.17
本文编号：2303197
[Abstract]:As an important part of environmental pollution, water pollution has a profound impact on people's normal and orderly life and production. There are a large number of low concentration phenolic organic pollutants which are difficult to biodegrade and highly toxic in organic wastewater. Seriously affect people's water safety. In view of the disadvantages of single photocatalytic oxidation and adsorption purification in the removal of organic pollutants in water, graphene hybrid zinc oxide composites (ZnO/rGO) were prepared by chemical reduction method. The interaction between ZnO and rGO was proved by characterization, and then graphene hybrid zinc oxide (Zn O/rGO) was combined with a large amount of graphene to prepare graphene hybrid zinc oxide composite hydrogel (ZnO/rGO-rGH) with macrostructure. When the loading amount of graphene in ZnO/rGO was 0.5 wt.%, the photodegradation efficiency of phenol reached 98% in 12 min, and the photodegradation efficiency of monomeric ZnO was 2.5 times higher than that of monomer ZnO. The surface hybrid structure formed by graphene and Zn O is conducive to the rapid transfer of photogenerated electrons to graphene, which greatly improves the photocatalytic activity of ZnO. The process of adsorption and purification of bisphenol A by composite hydrogel accords with the quasi-second-order kinetic equation model, and the adsorption isotherm conforms to the Langmuir isotherm model. The synergistic effect of ZnO/rGO-rGH adsorption photocatalysis on the purification of bisphenol A in solution was as high as 100, which realized the thorough purification of phenolic pollutants in water, and the macroscopical hydrogel structure was easy to recover. The purification efficiency of bisphenol A can still reach 90% after 5 times of repeated use of adsorbent photocatalysis, which can effectively solve the difficult problem of photocatalytic recovery of powder. By studying the synergistic effect of ZnO/rGO-rGH adsorption photocatalysis on the purification of bisphenol A in water with different initial concentration and different flow rate, it was found that the combined hydrogel could achieve the optimal flow rate of 0.48 mL / min within 16 h. The concentration of 10 mg L ~ (-1) bisphenol A was completely purified, while that of ZnO/rGO-rGH compound hydrogel was only maintained for 4 h by adsorption and purification. The results show that the synergistic effect of photocatalytic adsorption of composite hydrogels (ZnO/rGO-rGH) not only can effectively remove organic pollutants in water under static conditions, but also has significant advantages under convection dynamic conditions.
【学位授予单位】：华北理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X52;O648.17
【参考文献】
相关博士学位论文 前1条
1 徐婧;高比表面共轭材料的合成和环境净化性能研究[D];清华大学;2013年
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