Adsorption studies on the removal of malachite green by γ-Fe2O3/MWCNTs/Cellulose as an eco-friendly nanoadsorbent

A highly efficient eco-friendly nanoadsorbent i.e. γ-Fe 2 O 3 /MWCNTs/Cellulose was derived from waste tires and natural cellulose for malachite green removal from aqueous solutions through a chemical vapor deposition technique. The properties of the synthesized nanoadsorbent were identified using XRD, FESEM, EDX, TEM, EDS, DLS, FTIR, VSM, BET, XPS, and TGA. According to the results, the highest malachite green adsorption capacity was obtained by γ-Fe 2 O 3 /MWCNTs/cellulose 47.61 mg/g. In addition, the amount of dye adsorption increased with decreasing flow rate and enhancing column length from 9 to 3 mL/min and 2 to 10 min, respectively. The pseudo-second-order and the Langmuir model were the best kinetic and isothermal models to describe the malachite green adsorption process (R 2 > 99%). The thermodynamic results demonstrated that the adsorption process is exothermic and spontaneous. However, after 4 consecutive adsorption/desorption cycles, the removal efficiency was 87.35%. Therefore, γ-Fe 2 O 3 /MWCNTs/Cellulose can be considered as an outstanding adsorbent for malachite green removal.