新型三维多孔光热材料制备及其高盐废水处理应用

3D Porous Photothermal Materials for High Salt Wastewater Treatment

高盐废水处理存在处理难度大和能耗成本高等问题.近年来发展的界面光蒸汽水处理技术以绿色、高效和低能耗等特点成为了目前水资源回收利用领域的研究热点.本研究以纤维状结构的碳化氮(h-CN)修饰石墨烯(r-GO),通过水热反应制备了新型三维多孔石墨烯复合材料(3D h-CN/r-GO),并以硝基苯和苯酚作为模拟污染物,考察了其光热蒸发处理高盐废水的性能.研究结果表明,所制备的3D h-CN/r-GO材料具备宽光谱吸收范围和多级孔道结构,并呈现出快速热响应的特点.在模拟太阳光照条件下,光蒸汽转化效率可达90.4%.并且在处理过程中可实现硝基苯和苯酚等常见挥发性污染物的吸附,其吸附容量分别为67.6 mg·g^-1和57.5 mg·g^-1.而且,3D h-CN/r-GO可实现长时间稳定的光热水体蒸发回收,且对污染物及盐分截留率高达98%左右,冷凝水体达到污水处理的排放标准.因此,本研究为高盐废水的低能耗和低成本处理提供了一种新的技术.

The treatment of high salinity wastewater is complex with high cost and energy consumption.Interfacial solar vapor generation technology because of its green,high efficiency and low energy consumption has become a hot spot in the field of water resource recovery and utilization.In this study,a novel three-dimensional porous graphene composite material(3 D h-CN/r-GO)was designed by a hydrothermal reaction with fibrous carbon nitrogen(h-CN)modified graphene(r-GO),and its performance for adsorption of nitrobenzene and phenol as simulated contaminants via photothermal evaporation was studied.The results showed that 3 D h-CN/r-GO has a broad-spectrum absorption and multistage channel structure and presents the characteristics of fast thermal response.Its light steam conversion efficiency can reach 90.4%under the condition of simulated sunlight.The adsorption of nitrobenzene,phenol,and other common volatile pollutants can be realized in the process of treatment,and its adsorption capacities of nitrobenzene and phenol were 67.6 mg·g^-1 and 57.5 mg·g^-1,respectively.Moreover,3 D h-CN/r-GO can realize efficient interfacial solar vapor generation with long-time stability,and its retention rate of pollutants and salts is up to 98%.The recovery and utilization of steam condensate meets the discharge standard.Therefore,this study provides a promising way for the treatment of high salinity wastewater with low energy consumption and cost.