Use of reduced graphene oxide membranes for water treatment containing Cu and La ions

In recent years, the availability of drinking water, and in general of unpolluted water, has become a serious problem for many countries, and many efforts have been done to solve it. Different technological approaches have been proposed, among them liquid/solid adsorption has evidenced promising results. Several solids have been proposed as sorbent materials, however efficiency and selectivity towards metals capture are still open problems. In previous works, clays and activated carbons, pristine or modified with polyamines, have been studied. They were able to achieve interesting adsorption efficiency, but their properties were still not adequate to be applied at an industrial level. Therefore, the present work has been focused on the study of adsorption capability of reduced graphene oxide (rGO) membranes suggested in the scientific literature as promising solid sorbents for wastewater treatment. The experimental study has regarded the production of membranes of reduced GO, then their capture capability has been tested using La3+ and Cu2+, considered representative of heavy metals pollutants. Quantification of ions uptake has been performed on both mono-ionic and bionic La and Cu solutions. Membranes before and after the capture process have been characterized by means of different techniques, such as XRD, FT-IR, Raman spectroscopy, optical and SEM microscopy.