Efficient Removal Of U(VI) Ions from Aqueous Solutions by Tannic Acid/Graphene Oxide Composites

Bowu Zhu,Bin Liu,Fuxiang Song,Zhen Zhang,Zhijun Guo

doi:10.3390/app10248870

Abstract

Tannic acid/graphene oxide (TA/GO) composites were prepared in the present research, and their properties and sorption performance were evaluated by corresponding characterization methods and bath sorption experiments, respectively. The applications of TA/GO to remove U(VI) from aqueous solution were investigated with the maximum adsorption capacity of 87.8 mg·g−1 at low pH (pH = 3.6 ± 0.03). The sorption of U(VI) ions on TA/GO followed the Langmuir model because of the complexation of oxygen-containing functional groups on the surface of TA/GO composites and uranium ions. TA/GO manifested excellent selective adsorption toward uranium ions with other metal ions (Cs+, Sr2+, Co2+). Furthermore, TA/GO as an effective adsorbent was reused to remove a large amount of U(VI) ions from aqueous solution. Therefore, TA/GO is an ideal material to remove highly toxic U(VI) ions from wastewater.

Highlights

With the rapid development of modern industries, the generation of pollutants is posing major threats to environmental ecosystems and human health [1,2,3]
To solve the problem of the global energy crisis, nuclear energy is widely adopted as a new energy source [4]; it causes a certain side effect, nuclear wastes
The adsorption capacity of these adsorbents can only be used under higher pH conditions, hindering their practical applications [8]

Summary

Introduction

With the rapid development of modern industries, the generation of pollutants (organic pollutants, heavy metals, and radionuclides) is posing major threats to environmental ecosystems and human health [1,2,3]. Radioactive nuclides in nuclear wastes, such as 60 Co, 154 Eu, 232 Th, 235 U, 235 Np, 239 Pu, 241 Am, and 247 Cm, directly pollute surface water and groundwater resources [5,6] These radionuclides accumulate through food chains and cause radiation and biochemical damages to human organs due to their long-term radioactivity [7]. The safe disposal of nuclear wastes is a public concern [8] Numerous methods, such as chemical precipitation, ion exchange, membrane separation, and adsorption, have been used to separate and preconcentrate radionuclides from contaminated wastewater [9,10,11,12,13,14]. To preconcentrate and solidify radionuclides from wastewater, efficient and environment-friendly adsorbents are urgently needed [24]

Methods

Results

Conclusion