A comparative study of immobilizing ammonium molybdophosphate onto cellulose microsphere by radiation post-grafting and hybrid grafting for cesium removal

Zhen Dong; Jifu Du; Yanliang Chen; Manman Zhang; Long Zhao

doi:10.1016/j.envpol.2021.116432

A comparative study of immobilizing ammonium molybdophosphate onto cellulose microsphere by radiation post-grafting and hybrid grafting for cesium removal

Environ Pollut. 2021 Jan 5:273:116432. doi: 10.1016/j.envpol.2021.116432. Online ahead of print.

Authors

Zhen Dong¹, Jifu Du², Yanliang Chen³, Manman Zhang¹, Long Zhao⁴

Affiliations

¹ State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electric and Electronic Engineering, Huazhong University of Science and Technology, 430074, Wuhan, China.
² School of Nuclear Technology and Chemistry & Biology, Hubei University of Science and Technology, Xianning, 437100, China.
³ Shanghai Institute of Measurement and Testing Technology, 201203, Shanghai, China.
⁴ State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electric and Electronic Engineering, Huazhong University of Science and Technology, 430074, Wuhan, China. Electronic address: zhaolong@hust.edu.cn.

PMID: 33460869
DOI: 10.1016/j.envpol.2021.116432

Abstract

Ammonium molybdophosphate (AMP) exhibits high selectivity towards Cs but it cannot be directly applied in column packing, so it is necessary to prepare AMP-based adsorbents into an available form to improve its practicality. This work provided two AMP immobilized cellulose microspheres (MCC@AMP and MCC-g-AMP) as adsorbents for Cs removal by radiation grafting technique. MCC-g-AMP was prepared by radiation graft polymerization of GMA on microcrystalline cellulose microspheres (MCC) followed by reaction with AMP suspension, and MCC@AMP was synthesized by radiation hybrid grafting of AMP and GMA onto MCC through one step. The different structures and morphologies of two adsorbents were characterized by FTIR and SEM. The adsorption properties of two adsorbents against Cs were investigated and compared in batch and column experiments under different conditions. Both adsorbents were better obeyed pseudo-second-order kinetic model and Langmuir model. MCC-g-AMP presented faster adsorption kinetic and more stable structure, whereas MCC@AMP presented more facile synthesis and higher adsorption capacity. MCC@AMP was pH independent in the range of pH 1-12 but MCC-g-AMP was sensitive to pH for Cs removal. The saturated column adsorption capacities of MCC@AMP and MCC-g-AMP were 5.4 g-Cs/L-ad and 0.75 g-Cs/L-ad in column adsorption experiments at SV 10 h^-1. Both adsorbents exhibited very high radiation stability and can maintain an adsorption capacity of >85% even after 1000 kGy γ-irradiation. On the basis, two AMP-loaded adsorbents possessed promising application in removal of Cs from actual contaminated groundwater. These findings provided two efficient adsorbents for treatment of Cs in radioactive waste disposal.

Keywords: Ammonium molybdophosphate; Cs removal; Hybrid-grafting; Post-grafting; Radiation.