入侵植物生物炭负载Co/Fe双金属去除水中有机污染物的性能与机理研究

Performance and mechanism of invasive plants derived biochar-loaded Co/Fe for the removal of organic pollutants in water

以入侵植物钻叶紫菀、大狼耙草、意大利苍耳为生物质原材料,采用一步水热法和Co、Fe双金属掺杂制备了3种双金属催化剂,分别为Co-Fe-ASM、Co-Fe-BF、Co-Fe-XIM,它们均可有效活化过一硫酸盐(PMS)降解水中有机污染物.本研究以Co-Fe-ASM和磺胺甲噁唑(SMX)为模型催化剂和污染物,通过扫描电子显微镜、透射电镜、X射线光电子能谱等一系列技术对Co-Fe-ASM进行表征,考察了不同环境条件对Co-FeASM/PMS体系降解SMX性能的影响与催化剂的稳定性.同时,通过自由基清除实验和电子顺磁共振技术研究了活性物种(ROS).结果表明,Co-Fe-ASM能有效活化PMS,可在3 min中完全去除SMX.此外,Co-Fe-ASM/PMS体系在实际水样中可有效去除污染物,其中,非自由基途径对SMX降解起主导作用.综上所述,本研究为以入侵植物作为原材料通过一步水热法成功合成双金属生物炭催化剂提供了有效的方法,并为实现含有机污染物的污水处理提供了一种具有前景的策略.

In this study,three bimetallic biochar catalysts were prepared by one-step hydrothermal method using invasive plants as initial biomass,which can effectively activate peroxymonosulfate(PMS)to degrade organic pollutants in water.In this study,the invasive plants Aster subulatus Michx,Bidens frondosa L.and Xanthium italicum Moretti were used as initial biomass,and Co and Fe bimetals were doped to synthesize biochar catalysts,which were named Co-Fe-ASM,Co-Fe-BF and Co-Fe-XIM,respectively.Co-Fe-ASM and sulfamethoxazole(SMX)were selected as model catalysts and pollutants.Co-Fe-ASM was characterized by a series of techniques such as scanning electron microscopy,transmission electron microscopy,and Xray photoelectron spectroscopy.The effects of different environmental conditions on the Co-Fe-ASM/PMS system and the stability of the catalyst were investigated.Reactive oxygen species(ROS)were studied by radical scavenging experiments and electron paramagnetic resonance techniques.The results showed that Co-Fe-ASM could effectively activate PMS and completely remove SMX in 3 min.In addition,the Co-Fe-ASM/PMS system can effectively remove pollutants in actual water,and the non-radical pathway plays a leading role in the degradation of SMX.In conclusion,this study provides a promising strategy for the successful synthesis of bimetallic biochar catalysts by one-step hydrothermal method using invasive plants as raw materials,and to realize the treatment of organic polluted wastewater.