Enhanced nitrate, manganese, and phenol removal by polyvinyl alcohol/sodium alginate with biochar gel beads immobilized bioreactor: Performance, mechanism, and bacterial diversity

• Published in: Bioresource technology Vol. 348; p. 126818
• Main Authors: Wang, Yue, Su, Junfeng, Ali, Amjad, Chang, Qiao, Bai, Yihan, Gao, Zhihong
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.03.2022
• Subjects: Alginates; Bioreactors; Charcoal; Denitrification; Immobilized bioreactor; Manganese; Manganese-oxidizing bacteria; Microbial diversity; Nitrates; Phenol; Phenol removal; Phenols; Polyvinyl Alcohol; Denitrification; Microbial diversity; Manganese-oxidizing bacteria; Immobilized bioreactor; Phenol removal
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2022.126818

[Display omitted] •A powerful microbial immobilized biomaterial, PVA/SA@biochar gel beads were prepared.•Immobilized bioreactor removed nitrate, Mn(II), and phenol efficiently.•Manganese oxidation combined with adsorption to remove phenol.•Phenol stress reduced the diversity and abundance of microbial communities.•High-throughput showed that Zoogloea sp. played a vital role in the bioreactor. Water pollutants, such as nitrate, heavy metals, and organics have attracted attention due to their harms to environmental and biological health. A novel polyvinyl alcohol/sodium alginate with biochar (PVA/SA@biochar) gel beads immobilized bioreactor was established to remove nitrate, manganese, and phenol. The optimum conditions for preparing gel beads were studied by response surface methodology (RSM). Notably, the removal efficiencies of nitrate, Mn(II), and phenol were 94.64, 72.74, and 93.97% at C/N of 2.0; the concentrations of Mn(II) and phenol were 20 and 1 mg L−1, respectively. Moreover, addition of different concentrations of phenol significantly affected the components of dissolved organic matter, bacterial activity, and bioreactor performance. The biological manganese oxide (BMO) with three-dimensional petal-type structure produced during Mn(II) oxidation showed excellent adsorption capacity. The removal of phenol relied on a combination of biological action and adsorption processes. High-throughput analysis showed that Zoogloea sp. was the predominant bacterial group.