Yoon, So Yeon Kim, Min Ji Kim, Hye Won Lim, Seon Hwa Choong, Choe Earn Oh, Sang-Eun Kim, Jung Rae Yoon, Yeomin Choi, Jae young Ha Choi, Eun Jang, Min 2024-01-19T09:30:17Z 2024-01-19T09:30:17Z 2023-09-07 2023-06 0304-3894 https://pubs.kist.re.kr/handle/201004/113617 The aim of this study was to investigate the effects of hydrophilic sulfur-modified nanoscale zero-valent iron (S-nZVI) as a biocatalyst for denitrification. We found that the denitrifying bacteria Cupriavidus necator (C. necator) promoted Fe corrosion during biocatalytic denitrification, reducing surface passivation and sulfur species leaching from S-nZVI. As a result, S-nZVI exhibited a higher synergistic factor (fsyn = 2.43) for biocatalytic NO3 -removal than nanoscale zero-valent iron (nZVI, fsyn = 0.65) at an initial nitrate concentration of 25 mg L-1-N. Based on kinetic profiles, SO42-was the preferred electron acceptor over NO3 - when using C. necator and S-nZVI for biocatalytic denitrification. Up-flow column experiments demonstrated that biocatalytic denitrification using S-nZVI achieved a total nitrogen removal capacity of up to 2004 mg L-1 for 127 d. Notably, microbiome taxonomic profiling showed that the addition of S-nZVI to the groundwater promoted the growth of Geobacter, Desulfo-sporosinus, Streptomyces, and Simplicispira spp in the column experiments. Most of those microbes can reduce sulfate, promote denitrification, and match the batch kinetic profile obtained using C. necator. Our results not only discover the great potential of S-nZVI as a biocatalyst for enhancing denitrification via microbial activation but also provide a deep understanding of the complicated abiotic-biotic interaction. English Elsevier BV Hydrophilic sulfurized nanoscale zero-valent iron for enhancing in situ biocatalytic denitrification: Mechanisms and long-term column studies Article 10.1016/j.jhazmat.2023.131197 1 Journal of Hazardous Materials, v.452 Journal of Hazardous Materials 452 N scie scopus 001054041500001 2-s2.0-85151041127 Engineering, Environmental Environmental Sciences Engineering Environmental Sciences & Ecology Article HYDROGENOTROPHIC DENITRIFICATION NITRITE REDUCTASE NITRATE REMOVAL NANOPARTICLES REMEDIATION GROUNDWATER OXIDATION CR(VI) GROWTH PYRITE Nitrate Denitrification Groundwater S-nZVI Microbe