Drinking water purification by electron transfer from dissolved organic carbon to microorganisms via dual-electric centers.

Drinking water safety is confronted with escalating challenges from dissolved organic carbon (DOC) comprising natural organic matter (NOM) and micropollutants. Herein, multi-objective purification was carried out through a dual-electric centers Fe, Al-complexed graphene-like supported on commercial alumina (Fe, Al-GL/A2O3) biofilter for sand-filtered water from the Pearl River water source in China. About 31.8 % of all antibiotics in the raw water were removed, while C/N-disinfection byproducts formation potential (DBPFP) were decreased 33.2 % and 25.7 %, along with 32.3 % antibiotic resistance genes (ARGs) reduction and opportunistic pathogen suppression. These observations were superior to the conventional biological activated carbon (BAC) process that causes the accumulation of antibiotics with greater ARG and DBPFP. The unusual effects issue may from the synchronous destruction DBPs precursor and micropollutants through the electrons of electron-rich area of DOC persistently transferring to electroactive bacteria enriched on Fe, Al-GL/A2O3 by the charge transfer channel DOC → GL → Fe species → extracellular polymeric substance (EPS). All these came from DOC-EPS coordination on Fe, Al-GL/A2O3 inducing surface charge redistribution and stronger electric field. Notably, it also promoted exogenous electrons-facilitated electrotrophic and autotrophic microbial metabolism in the biofilter. This study achieved oxidant-free, multi-objective purification of drinking water, providing a practical, green, and sustainable strategy for ensuring drinking water safety.