Efficient remediation of Mn2+ and NH4+-N in co-contaminated water and soil by Acinetobacter sp. AL-6 synergized with grapefruit peel biochar: Performance and mechanism. (1st September 2022)

• Record Type: Journal Article
• Authors: Deng, Shuman; An, Qiang; Ran, Binbin; Yang, Zihao; Xu, Bohan; Zhao, Bin; Li, Zheng
• Is Part Of: Water research. Volume 223(2022)
• Publication Date: 2022-09-01
• Subjects: Mn2+ immobilization -- Water treatment -- Soil remediation -- Heterotrophic nitrifying bacteria -- Grapefruit peel biochar; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2022.118962
• Languages: English
• ISSNs: 0043-1354

Abstract

Highlights: BC and strain AL-6 removed Mn 2+ (99.3%) and NH4 + -N (97.7%) in complex water body. The metabolism of N and C were mutual promotion by BC and strain AL-6. BC and strain AL-6 immobilized Mn 2+ and NH4 + -N, and increased soil fertility. BC and strain AL-6 increased abundance of functional bacteria. Abstract: Electrolysis manganese slag produced in industrial manganese production causes massive leachate containing heavy metal Mn 2+ and inorganic NH4 + -N, which causes serious hazard to the water body and soil. A cost-effective alternative to address the multiple pollution is urgently needed. This study investigated the synergy of grapefruit peel biochar (BC) and strain AL-6 to remediate Mn 2+ and NH4 + -N in sequencing batch bioreactor (SBR) and soil column. The results showed that, in SBR, under the condition of C/N 5, temperature 30°C, BC and strain AL-6 showed fabulous performance to remove Mn 2+ (99.3%) and NH4 + -N (97.7%). The coexisting ions Mg 2+ and Ca 2+ had no effects on the removal of Mn 2+ and COD, however, 23.3% removal efficiency of NH4 + -N was curtailed. Characterization found that the presence of MnCO3 confirmed the adsorption of Mn 2+ by functional groups action, and gas chromatography indicated that BC and strain AL-6 promoted the reduction of N2 O and organic carbon. In addition, BC and strain AL-6 helped to immobilize 799.41 mg L −1 of Mn 2+ and 320 mg L −1 of NH4 + -N after 45 d in the soil column. And the determination of TOC, CEC, pH, Eh, soil enzymatic activity (catalase and urease), and microbial diversity and abundance confirmed that BC and strain AL-6 increased the soil fertility and bioavailability of pollutants. Totally, BC and strain AL-6 possess great potential to remediate Mn 2+ and NH4 + -N pollution in water and soil. Graphical abstract: Image, graphical abstract