Sequestration of Ni(II) and Cu(II) using FeSO4 modified Zea mays husk magnetic biochar: Isotherm, kinetics, thermodynamic studies and RSM
Runit Isaac, Shaziya Siddiqui
Abstract
The present study was established to develop a magnetically modified iron oxide immobilised potentially low cost biochar adsorbent derived from Zea mays husk (FEZB) for the effective removal of copper and nickel from the aqueous solution. The contact and bonding between the adsorbent and adsorbate was characterized using FTIR, FESEM, EDX, XRD, and BET. The process of adsorption was studied under the impact of varying plights viz. pH (2–12), concentration of the adsorbate (10–100 mg L−1), contact time (5–240 min), and temperature (288–308 K) in batch mode. The optimization conditions achieved were: pH 6, initial concentration of 50 ppm and equilibrium time of 120 min and 90 min for 98.00% of copper and 97.44% of nickel removal, respectively. The result deduced that the kinetic data is governed by the pseudo second order model and the equilibrium adsorption data was well fitted in the Langmuir isotherm, with the monolayer adsorption capacity of 23.60 mg g−1 for copper and 22.53 mg g−1 for nickel. The thermodynamic results demonstrated that the process is endothermic and spontaneous. I-optimal design of RSM was used to statistically study the optimization. The desorption, regeneration, efficient disposal and cost effectiveness of the adsorbent was studied.