Selective removal of cesium by ammonium molybdophosphate - polyacrylonitrile bead and membrane

Dahu Ding; Zhenya Zhang; Rongzhi Chen; Tianming Cai

doi:10.1016/j.jhazmat.2016.11.054

Selective removal of cesium by ammonium molybdophosphate - polyacrylonitrile bead and membrane

J Hazard Mater. 2017 Feb 15;324(Pt B):753-761. doi: 10.1016/j.jhazmat.2016.11.054. Epub 2016 Nov 21.

Authors

Dahu Ding¹, Zhenya Zhang², Rongzhi Chen³, Tianming Cai⁴

Affiliations

¹ College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China; Graduate School of Life and Environmental Science, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan. Electronic address: ddh@njau.edu.cn.
² Graduate School of Life and Environmental Science, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.
³ College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100044, China.
⁴ College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: ctm@njau.edu.cn.

PMID: 27890359
DOI: 10.1016/j.jhazmat.2016.11.054

Abstract

The selective removal of radionuclides with extremely low concentrations from environmental medium remains a big challenge. Ammonium molybdophosphate possess considerable selectivity towards cesium ion (Cs⁺) due to the specific ion exchange between Cs⁺ and NH₄⁺. Ammonium molybdophosphate - polyacrylonitrile (AMP-PAN) membrane was successfully prepared for the first time in this study. Efficient removal of Cs⁺ (95.7%, 94.1% and 91.3% of 1mgL^-1) from solutions with high ionic strength (400mgL^-1 of Na⁺, Ca²⁺ or K⁺) was achieved by AMP-PAN composite. Multilayer chemical adsorption process was testified through kinetic and isotherm studies. The estimated maximum adsorption capacities even reached 138.9±21.3mgg^-1. Specifically, the liquid film diffusion was identified as the rate-limiting step throughout the removal process. Finally, AMP-PAN membrane could eliminate Cs⁺ from water effectively through the filtration adsorption process.

Keywords: Desorption; Kinetic; Liquid film diffusion; Moving boundary model; Radioactive contamination.