Fabrication and characterization of a novel (GO/PAA/PAM) nanocomposite as effective adsorbent for cationic dyes

In this work, we study the modification of graphene oxide with polyacrylic acid and acrylamide (GO/PAA/PAM) through free radical single polymerization step to adsorb methylene blue (MB) and crystal violet (CV)-dyes in single and binary-systems from aqueous media. (GO/PAA/PAM) was characterized before and after adsorption processes. Thermogravimetric analysis provides useful data about the functionalization process, where the polymers will be bounded with the GO at the surface OH groups and the composite mainly composed of the polymers chains. The adsorption kinetic obeys the pseudo-second-order for the two dyes in the single and binary systems. Moreover, according to Langmuir isotherm in the single systems, the sorption of CV (357.14 mg g−1) is more than MB (344.8 mg g−1). On contrary, in the binary system, the MB (323.56 mg g−1) is preferably adsorbed by the (GO/PAA/PAM) composite than CV (172.41 mg g−1). Furthermore, the (GO/PAA/PAM) composite exhibited acceptable recycling over five runs. Finally, a real dye sample was applied to appreciate the efficiency of the prepared material in the industrial field. This novel composite can be used on a large scale for purification, remediation, and numerous industrial processes due to its promising properties.