Poly(vinyl alcohol)/modified porous starch gel beads for microbial preservation and reactivation: preparation, characterization and its wastewater treatment performance

Shutao Lin; Ruiting Chang; Xinyu Cao; Yongheng Zhang; Jiabo Chen; Wenchao Jiang; Zhi Zhang

doi:10.1039/d3ra05371g

Poly(vinyl alcohol)/modified porous starch gel beads for microbial preservation and reactivation: preparation, characterization and its wastewater treatment performance

RSC Adv. 2023 Oct 13;13(43):30217-30229. doi: 10.1039/d3ra05371g. eCollection 2023 Oct 11.

Authors

Shutao Lin^{1

2}, Ruiting Chang², Xinyu Cao², Yongheng Zhang², Jiabo Chen², Wenchao Jiang², Zhi Zhang^{1

2}

Affiliations

¹ Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University Chongqing 400045 China zhangzhicqu@cqu.edu.cn.
² College of Environment and Ecology, Chongqing University Chongqing 400045 China wchjiang@qq.com.

Abstract

Poly(vinyl alcohol) (PVA)/modified porous starch (MPS) gel beads were prepared through in situ chemical cross-linking by incorporating with MPS, which was obtained by modifying porous starch (PS) with polyethyleneimine (PEI) and glutaraldehyde (GA). Addition of MPS could improve the storage modulus and the effective crosslinking density (v_e) of the gel beads, and the mechanical properties were enhanced. The PVA-MPS gel beads were preserved as immobilized microbial carriers for 40 d and reactivated in wastewater. Scanning electron microscope (SEM) observations showed that the beads were highly porous and conducive for microorganism adhesion. The PVA-MPS gel beads were able to remove 97% of ammonia nitrogen and 80% of chemical oxygen demand (COD) after reactivation under all four preservation conditions. The abundance of Hydrogenophaga as denitrifying bacteria on PVA-MPS gel beads increased, with abundance of 8.44%, 5.55%, 8.90% and 9.48%, respectively. It proved that the carrier provided a partial hypoxic environment for microorganisms.