title: Superior coagulation of graphene oxides on nanoscale layered double hydroxides and layered double oxides.
abstract: With the development and application of graphene oxides (GO), the potential toxicity and environmental behavior of GO has become one of the most forefront environmental problems. Herein, a novel nanoscale layered double hydroxides (glycerinum-modified nanocrystallined Mg/Al layered double hydroxides, LDH-Gl), layered double oxides (calcined LDH-Gl, LDO-Gl) and metallic oxide (TiO2) were synthesized and applied as superior coagulants for the efficient removal of GO from aqueous solutions. Coagulation of GO as a function of coagulant contents, pH, ionic strength, GO contents, temperature and co-existing ions were studied and compared, and the results showed that the maximum coagulation capacities of GO were LDO-Gl (448.3 mg g-1) > TiO2(365.7 mg g-1) > LDH-Gl (339.1 mg g-1) at pH 5.5, which were significantly higher than those of bentonite, Al2O3, CaCl2or other natural materials due to their stronger reaction active and interfacial effect. The presence of SO32-and HCO3-inhibited the coagulation of GO on LDH-Gl and LDO-Gl significantly, while other cations (K+, Mg2+, Ca2+, Ni2+, Al3+) or anion (Cl-) had slightly effect on GO coagulation. The interaction mechanism of GO coagulation on LDO-Gl and TiO2might due to the electrostatic interactions and strong surface complexation, while the main driving force of GO coagulation on LDH-Gl might be attributed to electrostatic interaction and hydrogen bond, which were further evidenced by TEM, SEM, FT-IR and XRD analysis. The results of natural environmental simulation showed that LDO-Gl, TiO2or other kinds of natural metallic oxides could be superior coagulants for the efficient elimination of GO or other toxic nanomaterials from aqueous solutions in real environmental pollution cleanup.
authors: School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206, PR China; School of Chemistry, Biological and Materials Sciences, East China Institute of Technology, Nanchang 330013, PR China.
authors: Yidong
authors: Y
authors: Zou
authors: School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206, PR China.
authors: Xiangxue
authors: X
authors: Wang
authors: School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206, PR China.
authors: Zhongshan
authors: Z
authors: Chen
authors: School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206, PR China.
authors: Wen
authors: W
authors: Yao
authors: School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206, PR China. Electronic address: aiyuejie314@126.com.
authors: Yuejie
authors: Y
authors: Ai
authors: School of Chemistry, Biological and Materials Sciences, East China Institute of Technology, Nanchang 330013, PR China. Electronic address: walton_liu@163.com.
authors: Yunhai
authors: Y
authors: Liu
authors: Department of Mathematics, Quaid-I-Azam University, Islamabad 44000, Pakistan; NAAM Research Group, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
authors: Tasawar
authors: T
authors: Hayat
authors: NAAM Research Group, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
authors: Ahmed
authors: A
authors: Alsaedi
authors: Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah, 21589 Saudi Arabia.
authors: Njud S
authors: NS
authors: Alharbi
authors: School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206, PR China; NAAM Research Group, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia. Electronic address: xkwang@ipp.ac.cn.
authors: Xiangke
authors: X
authors: Wang
mesh_terms: D000327:Adsorption; D003029:Coagulants / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D006878:Hydroxides / Q000737:chemistry*; D007700:Kinetics; D009994:Osmolar Concentration; D010087:Oxides / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D055672:Static Electricity; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D003029:Coagulants; D006878:Hydroxides; D010087:Oxides; D014867:Water; D006108:Graphite
keywords: Coagulation; Environmental simulation; Graphene oxide; Mechanism; Natural water