Synthesis of graphene@Fe3O4@polyaniline nanocomposite for simultaneous removal of a binary mixture of Malachite Green cationic dye and Acid Red 1 anionic dye from aqueous solutions

The current work shows the effective removal of the binary combination of Malachite Green (MG) and Acid Red 1 (AR1) dyes using a graphene@Fe3O4@polyaniline nanocomposite (Gr@Fe3O4@PANI NPs). The response surface methodology-central composite design (RSM-CCD) was used to assess the influence of independent factors such as solution pH, contact time, initial concentration of each dye, and adsorbent mass. The coefficient of determination (R2) and adjusted R2 (R2adj) values for MG (R2=0.9956 and R2adj=0.9875) and AR1 (R2=0.9954 and R2adj=0.9870) dyes was determined, indicating that the resulting model is appropriate for data analysis. The quadratic model was shown to be the best model for identifying the interaction of study variables by one-way ANOVA analysis of variance (p 0.0001). The pH=6.5, concentration for each dye of 16 mg L-1, adsorbent mass 0.03 g, and contact time of 24 min were shown to be optimal for MG and AR1 dye adsorption. . Finally, due to the high adsorption capacity of the synthesized adsorbent, the adsorbent recovery capability in 5 consecutive cycles for mixing both dyes was investigated.