Efficient novel amphiphilic double shells layer coupled with nanoscale zero-valent composite for the degradation of trichloroethylene

Can Li; Qiang Lu; Cong Zhan; Muhammad Tariq; Kai Huang; Fuwen Liu; Fei Zhu; Guanhong Liu; Changzheng Cui; Kuangfei Lin

doi:10.1016/j.scitotenv.2018.12.301

Efficient novel amphiphilic double shells layer coupled with nanoscale zero-valent composite for the degradation of trichloroethylene

Sci Total Environ. 2019 Apr 1:659:821-827. doi: 10.1016/j.scitotenv.2018.12.301. Epub 2018 Dec 28.

Authors

Can Li¹, Qiang Lu², Cong Zhan¹, Muhammad Tariq¹, Kai Huang¹, Fuwen Liu¹, Fei Zhu¹, Guanhong Liu¹, Changzheng Cui¹, Kuangfei Lin³

Affiliations

¹ State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China.
² State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China. Electronic address: qianglu@ecust.edu.cn.
³ State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China. Electronic address: kflin@ecust.edu.cn.

PMID: 31096412
DOI: 10.1016/j.scitotenv.2018.12.301

Abstract

An efficient novel amphiphilic material composed of core-double shells nanocomposite (CDSN) with nanoscale zero-valent iron (NZVI) as the core and PS₁₀₀-b-PAA₁₆ as inner shell and chitosan as outmost shell has been synthesized successfully. Its application to remove the trichloroethylene (TCE) in stimulated TCE solution with 7.3 ± 0.3 mg/L dissolved oxygen was investigated. The results showed that CDSN after exposure to air for a month could still remove 92.6% of TCE as compared to 61.5% removal rate of NZVI in 360 min (the gram ratio of material: TCE equals to 10:1), exhibiting the great oxidation resistance performance. Specifically, dynamic research of the total removal divided into adsorption by shell layer and degradation by reducibility of NZVI at a predetermined interval was engaged to understand the complete mass transfer process of TCE. The results revealed that CDSN adsorbed 1.5 to 2 folds time TCE as compared to NZVI in the same initial pH = 8.5 aqueous solution. Importantly, CDSN could sustain fixed reactivity to remove about 94.8% of TCE from the start to end. NZVI exhibited greater removal capacity in first 180 min, but later it lost the reducibility and finial removal rate was 89%. The selective adsorption to protonated CDSN was strengthened to increase the removal of TCE at pH 3.5 while NZVI had a worse removal in pH 3.5 performance than pH 8.5.

Keywords: CDSN; Groundwater remediation; Oxidation resistance; Strong adsorption; Trichloroethylene.