Enhanced anaerobic degradation of highly-concentrated phenolic wastewater by novel system of microcurrent-coupled magnetic layered double hydride biochar

This report presents a novel system combining microcurrent-coupled magnetic layered double hydroxide and biochar to enhance the anaerobic degradation performance of highly-concentrated phenolic wastewater. The coupled system achieves removal efficiencies for COD and 2,4,6-trichlorophenol (2,4,6-TCP) of 71.1 % and 75.40 %, respectively, which are 2.25 and 2.50 times higher than those achieved by raw sludge. Furthermore, the developed system exhibits elevated levels of coenzyme F420 and extracellular polymeric substances, as well as enhanced electron transport activity in the activated sludge. Microbial community analysis indicates that the electrical connection between enriched Chloroflexi and Methanothrix enables the enhancement of direct inter species electron transfer, thereby promoting the anaerobic degradation of 2,4,6-TCP. Metagenomic functional succession results indicate varying degrees of alteration in microbial COG function, carbohydrate-active enzyme activity, and metabolic pathways. The application of this method overcomes the bottleneck in anaerobic systems for the efficient breakdown of refractory pollutants, which holds significant practical implications.