Preparation of polyamidoamine dendrimers functionalized magnetic graphene oxide for the adsorption of Hg(II) in aqueous solution

Ying-Xia Ma; Dan Xing; Wen-Jie Shao; Xue-Yan Du; Pei-Qing La

doi:10.1016/j.jcis.2017.05.104

Preparation of polyamidoamine dendrimers functionalized magnetic graphene oxide for the adsorption of Hg(II) in aqueous solution

J Colloid Interface Sci. 2017 Nov 1:505:352-363. doi: 10.1016/j.jcis.2017.05.104. Epub 2017 May 27.

Authors

Ying-Xia Ma¹, Dan Xing², Wen-Jie Shao², Xue-Yan Du³, Pei-Qing La²

Affiliations

¹ State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Key Laboratory of Nonferrous Metal Alloys and Processing, Ministry of Education, School of Materials Science & Engineering, Lanzhou University of Technology, Lanzhou 730050, China. Electronic address: mayx2011818@163.com.
² State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Key Laboratory of Nonferrous Metal Alloys and Processing, Ministry of Education, School of Materials Science & Engineering, Lanzhou University of Technology, Lanzhou 730050, China.
³ State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Key Laboratory of Nonferrous Metal Alloys and Processing, Ministry of Education, School of Materials Science & Engineering, Lanzhou University of Technology, Lanzhou 730050, China. Electronic address: duxy@lut.cn.

PMID: 28601744
DOI: 10.1016/j.jcis.2017.05.104

Abstract

In this study, using graphene oxide supported Fe₃O₄ nanoparticles as carriers, ethylenediamine and methyl acrylate as functional monomer, different generations of polyamidoamine dendrimers functionalized magnetic graphene oxide (MGO-PAMAM), up to generation 4.0, were successfully synthesized via step by step growth chemical grafting approach and magnetic separation technology. In the process of synthesizing dendrimers, the generation of dendrimers was increased with the increasing of reaction cycles. In other words, the dendrimers generation is determined from the number of branch iterations. The obtained MGO-PAMAM were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), elemental analysis, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), nitrogen adsorption/desorption isotherm and Zeta potential analysis. The adsorption properties of the synthesized products for Hg(II) in aqueous solution were investigated by batch experiments. The results showed that the MGO-PAMAM with generation 3.0 of dendrimers (MGO-PAMAM-G3.0) has the maximum adsorption capacity of 113.71mg·g^-1. The adsorption process of MGO-PAMAM-G3.0 for Hg(II) was well described by the pseudo-second-order kinetics model and the Langmuir isotherm model. The Hg(II) adsorbed on the surface of MGO-PAMAM-G3.0 was reduced to Hg(I) in the adsorption process. In addition, the MGO-PAMAM possesse good magnetic separation performance.

Keywords: Adsorption; Dendrimers; Hg(II); Magnetic graphene oxide; Polyamidoamine.