Magnetic pomegranate peels activated carbon (MG-PPAC) composite for Acid Orange 7 dye removal from wastewater

Abstract

A magnetic pomegranate peels activated carbon (MG-PPAC) composite was prepared as an effective adsorbent for Acid Orange 7 (AO7) dye removal from wastewater. The effects of impregnation ratio and activation temperatures (600–900°C) on the specific surface area, and pore morphology were studied. The synthesized composite MG-PPAC was considered by BET, SEM, EDX, FT-IR, XRD and VSM. The prepared magnetic composite at 700°C activation temperature and impregnation ratio 1/2 (peels/ZnCl2) exhibited 513.34 m2 g− 1 surface area, 0.4025 cm3 g–1 volume of the total pores, and 3.1364 nm mean diameter of the pores. The magnetization saturation (Ms), remanence (Mr) and coercivity (Hc) of the MG-PPA composite were 14.116 emu/g, 0.50685 emu/g, and 19.705 G, respectively. Also, the composite MG-PPAC was in a super-paramagnetic state at room temperature and could be gathered within 5 S (less than 5 S) with an external magnetic field. Impact of pH, adsorbent dose, initial concentration of adsorbate (AO7 dye), and time of contact have been studied to optimize the removal process. The Langmuir (LIM), Freundlich (FIM) and Tempkin (TIM) isotherm models were used to investigate MG-PPAC adsorption behavior for AO7 dye. Applicability of Langmuir isotherm model (LIM) demonstrates a monolayer adsorption AO7 dye removal process, and the maximum monolayer capacity (Qm) attained from linear solvation of LIM is 322.58 mg g–1. Also, the adsorption process was tested using PFOM, PSOM, IPDM, FDM, and E. The pseudo-second order model is well-fitted to the operational data of AO7 dye removal (R2 = 0.983–1.0) related to the other kinetic models.