Choong, Choe Earn Yoon, So Yeon Wong, Kien Tiek Kim, Minhee Lee, Gooyong Kim, Sang-Hyoun Jeon, Byong-Hun Choi, Jaeyoung Yoon, Yeomin Ha Choi, Eun Jang, Min 2024-01-19T10:03:24Z 2024-01-19T10:03:24Z 2023-06-01 2023-02 1385-8947 https://pubs.kist.re.kr/handle/201004/113995 We prepared hydrophobic sulfur (S) core-shell-layered nano-zero-valent iron (Fe) (S-nZVI) via a post-sulfidation method with varying Fe/S mass ratios for NO3- reduction. Notably, S(0.125)ZVI (Fe/S = 0.125) showed good N-O cleavage properties owing to its high electron (e(-)) transfer efficiency and low surface passivation. As a result, the S(0.125)ZVI exhibited higher selectivity of NO3- reduction toward N-2 than sole nZVI in synthetic and actual NO3- groundwater in batch experiments. Density functional theory (DFT) calculations showed that H-2 evolution over S-nZVI was suppressed by the S atom in the hollow site of the Fe(1 1 0) surface, resulting in nearly 100 % denitrification selectivity. Quenching tests revealed that e(-) transfer through the S atom toward the surface bounded by NOx species is the dominant denitrification mechanism of S-nZVI. Up-flow column tests using actual groundwater were conducted for 127 d, and S(0.125)ZVI demonstrated a removal capacity of up to 1907 mg-N/g NO3-. Field experiments using S0.125ZVI for NO3- -contaminated groundwater remediation were conducted over four months, confirming that S-nZVI may be an alternative to nZVI for in situ groundwater remediation. English Elsevier BV Hydrophobic sulfur core-shell layered metallic iron for nitrate reduction with nearly 100% dinitrogen selectivity: Mechanism and field studies Article 10.1016/j.cej.2022.140083 1 Chemical Engineering Journal, v.454 Chemical Engineering Journal 454 N scie scopus 000990152600001 2-s2.0-85141530135 Engineering, Environmental Engineering, Chemical Engineering Article ZERO-VALENT IRON REMOVAL NANO WATER PARTICLES NZVI PH Zero-valent iron Sulfur Nitrate reduction Field test