A Novel Coordination Polymer as Adsorbent Used to Remove Hg(II) and Pb(II) from Water with Different Adsorption Mechanisms

Rui-Dong Wang; Mei He; Zhihao Li; Zongling Niu; Rong-Rong Zhu; Wen-Qian Zhang; Suoshu Zhang; Lin Du; Qi-Hua Zhao

doi:10.1021/acsomega.1c06606

A Novel Coordination Polymer as Adsorbent Used to Remove Hg(II) and Pb(II) from Water with Different Adsorption Mechanisms

ACS Omega. 2022 Mar 15;7(12):10187-10195. doi: 10.1021/acsomega.1c06606. eCollection 2022 Mar 29.

Authors

Rui-Dong Wang¹, Mei He¹, Zhihao Li¹, Zongling Niu¹, Rong-Rong Zhu¹, Wen-Qian Zhang², Suoshu Zhang¹, Lin Du^{1

3}, Qi-Hua Zhao^{1

3}

Affiliations

¹ School of Chemical Science and Technology, Yunnan University, Kunming 650091, People's Republic of China.
² College of Pharmaceutical Engineering, Xinyang Agricultural and Forestry University, Henan, 464000, People's Republic of China.
³ Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan Research & Development Center for Natural Products, Yunnan University, Kunming 650091, People's Republic of China.

Abstract

Under the hydrothermal condition, a new type of two-dimensional coordination polymer ([Cd(D-Cam)(3-bpdb)]_n, Cd-CP) has been constructed. It is composed of D-(+)-Camphoric-Cd(II) (D-cam-Cd(II)) one-dimensional chain and bridging 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene (3-bpdb) ligands. Cd-CP has a good removal effect for Hg(II) and Pb(II), and the maximum adsorption capacity is 545 and 450 mg/g, respectively. Interestingly, thermodynamic studies have shown that the adsorption processes of Hg(II) and Pb(II) on Cd-CP use completely different thermodynamic mechanisms, in which the adsorption of Hg(II) is due to a strong electrostatic interaction with Cd-CP, while that of Pb(II) is through a weak coordination with Cd-CP. Moreover, Cd-CP has a higher affinity for Hg(II), and when Hg(II) and Pb(II) coexist, Cd-CP preferentially adsorbs Hg(II).