Synthesis of graphene oxide nanoribbons/chitosan composite membranes for the removal of uranium from aqueous solutions

In this study, a graphene oxide nanoribbons/chitosan (GONRs/CTS) composite membrane was successfully prepared by encapsulating CTS into GONRs, which were unzipped from multi-walled carbon nanotubes. The GONRs/CTS composite membrane so prepared was characterized using scanning electron microscopy, X-Ray diffraction and Fourier transform infrared spectroscopy. The effects of the experimental conditions such as the pH (2-7), adsorbent dosage (10-50 mg), experimental time (5 min-32 h), uranium concentration (25-300 mg center dot L-1), experimental temperature (298 K-328 K) on the adsorption properties of the composite membrane for the removal of U(VI) were investigated. The results showed that the U(VI) adsorption process of the GONRs/CTS composite membrane was pH-dependent, rapid, spontaneous and endothermic. The adsorption process followed the pseudosecondary kinetics and Langmuir models. The maximum U(VI) adsorption capacity of the GONRs/CTS composite membrane was calculated to be 320 mg center dot g(-1). Hence, the GONRs/CTS composite membrane prepared in this study was found to be suitable for separating and recovering uranium from wastewater.