Preparation of the crosslinked GO/PAA aerogel and its adsorption properties for Pb(II) ions

Abstract

The graphene oxide(GO)/polyacrylic acid(PAA) was prepared by in situ polymerization in graphene oxide lamellae, and crosslinked graphene oxide/polyacrylic acid complex(CLGO/PAA) was formed by esterification reaction between 1,4-butanediol and carboxylic acid of PAA at same time. The CLGO/PAA aerogel was prepared by freeze drying method. The CLGO/PAA aerogel has good stability and high saturated adsorption capacity for the adsorption of Pb(II) ions in water. The structure and properties of the CLGO/PAA aerogel were characterized by using x-ray diffractometry(XRD), field emission scanning electron microscopy (FESEM), infrared spectroscopy(FT-IR), and atomic absorption spectrometer(AAS), respectively. The results show that the prepared CLGO/PAA aerogel possess elliptical pore structure. In addition, the adsorption properties of the CLGO/PAA aerogel for Pb(II) in water were studied under different pH, different concentrations of Pb(II), contact time and number of adsorbent cycles. The results show that the adsorption amount of Pb(II) could reach to 640 mg g ^−1 at the initial concentration of Pb(II) was 500 mg l ^−1 , and the adsorption equilibrium could be reached after 60 min. The adsorption amount for Pb(II) was still 143 mg g ^−1 after 5 times cycle.

Keywords

• crosslinked
• graphene oxide
• polyacrylic acid
• aerogel
• Pb(II)
• adsorption