生物质原位碳热制备多孔biochar载铁基电Fenton催化剂的过程调控和机理解析

Waste biomass is a category of organic solid waste widely found in the world. How to effectively recover resource from it and harmlessly dispose it is still a problem with widespread concerns. In this research, we proposed to pyrolyze the Fe(III) preloaded biomass, with the in-situ carbothermal effects in the biomass pyrolysis process, to synthesize the porous biochar support Fe based nanomaterials. The as-synthesized material was used as a catalyst for the electro-Fenton degradation of 4-chlorophenol. We proposed to on-line monitor the biomass pyrolysis process through TG-FTIR-MS, analyze the changes of Fe species during the carbothermal process using the high temperature XRD technology, and thus illuminating the process and mechanism of the in-situ carbothermal reduction of Fe(III) during the biomass pyrolysis process. Based on these results, we goal-directed tuned the parameters of biomass process, so that to obtain the biochar support Fe based nanomaterials with high catalytic activity and chemical stability. Thereafter, we study the process of electro-Fenton degradation of 4-chlorophenol in detail, illuminating the influence of catalyst chemical state, structure, morphology, and loading amount on the pollutant degradation efficiency in the near-neutral pH electro-Fenton process. This research will provide a new strategy and scientific basis on the harmless disposal and resource recovery from the large scale waste biomass, as well as cost-effective and controllable synthesis of the catalyst materials for electro-Fenton degradation of pollutants.

废弃生物质是目前大量存在的一类固体废弃物，如何实现对其无害化处置及资源化利用是一个广泛关注的问题。本项目拟将预负载Fe(III)的生物质进行热解，通过生物质原位碳热还原过程，制备多孔biochar负载铁基纳米材料，并将其作为电Fenton反应催化剂，研究其对4-氯酚的降解过程和影响因素。本项目拟通过热重-红外-质谱联用和高温XRD技术对生物质热解和高价铁碳热还原过程进行在线监测，阐明高价铁化合物原位碳热还原过程及其机理，在此基础上对热解过程进行调控，获得具有较高催化活性和稳定性的多孔biochar负载铁基纳米材料。并对其催化电Fenton反应过程进行深入分析，阐明催化剂形态、结构、形貌、负载量等对近中性pH条件下电Fenton反应过程影响机制。本项目研究将为废弃生物质无害化处置和资源化利用，以及电Fenton反应催化材料低成本，可控制备提供新的思路和科学依据。

废弃生物质是目前大量存在的一类固体废弃物，如何实现对其无害化处置及资源化利用是一个广泛关注的问题。本项目将预负载Fe(III)的生物质进行热解，通过生物质原位碳热还原过程，制备多孔biochar负载铁基纳米材料，并将其作为电Fenton反应催化剂，研究其对难降解有机污染物的降解过程和影响因素。我们通过各种物理化学的表征手段，阐明高价铁化合物原位碳热还原过程及其机理，在此基础上对热解过程进行调控，获得具有较高催化活性和稳定性的多孔biochar负载铁基纳米材料。将所得的biochar作为阴极电催化剂，对其催化电Fenton反应过程进行深入分析，我们发现多孔biochar负载铁基纳米材料对电Fenton过程具有很好的催化活性，可以高效的实现对难降解有机污染物的降解去除，同时，该催化剂具有非常优异的循环稳定性，多次循环使用之后，其催化活性不仅未见降低，反而有明显的提升，我们对这个反常现象进行了深入的研究，发现催化剂在电化学反应过程中产生的界面相变现象可以使得更多的催化位点暴露，从而提高其催化活性。本项目研究将为废弃生物质无害化处置和资源化利用，以及电Fenton反应催化材料低成本，可控制备提供新的思路和目标。