Mechanochemical destruction of DDTs with Fe-Zn bimetal in a high-energy planetary ball mill

Hong Sui; Yuzhou Rong; Jing Song; Dongge Zhang; Haibo Li; Peng Wu; Yangyang Shen; Yujuan Huang

doi:10.1016/j.jhazmat.2017.08.025

Mechanochemical destruction of DDTs with Fe-Zn bimetal in a high-energy planetary ball mill

J Hazard Mater. 2018 Jan 15:342:201-209. doi: 10.1016/j.jhazmat.2017.08.025. Epub 2017 Aug 12.

Authors

Hong Sui¹, Yuzhou Rong², Jing Song³, Dongge Zhang², Haibo Li², Peng Wu², Yangyang Shen⁴, Yujuan Huang⁴

Affiliations

¹ School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; National Engineering Research Center for Distillation Technology (NERCDT), Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China.
² School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China.
³ Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: jingsong@issas.ac.cn.
⁴ Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.

PMID: 28837881
DOI: 10.1016/j.jhazmat.2017.08.025

Abstract

Mechanochemical destruction has been proposed as a promising, non-combustion technology for the disposal of toxic, halogenated, organic pollutants. In the study presented, additives including Fe, Zn, Fe-Zn bimetal, CaO and Fe₂O₃ were tested for their effectiveness to remove DDTs by MC. The results showed that Fe-Zn bimetal was the most efficient additive, with 98% of DDTs removed after 4h. The Fe-Zn mass ratio was optimized to avoid possible spontaneous combustion of the ground sample during subsample collection. Inorganic water-soluble chloride in the ground sample increased by 91% after 4h of grinding, which indicated dechlorination during destruction of DDTs. In addition, relationships were established between the rate constant and the rotation speed or the charge ratio. Discrete Element Method (DEM) modeling was used to simulate the motion of the grinding ball and calculate both total impact energy and normal impact energy. The latter expressed a stronger, linear correlation with the rate constant. Therefore, normal impact energy is proposed to be the main driving force in the MC destruction of DDTs.

Keywords: DDTs; DEM modeling; Impact energy; Iron-zinc bimetal; Mechanochemistry.