Investigation on the effective remediation of quinoline at solid/solution interface using modified agricultural waste: an inclusive study

This research work explores the potential of modified agricultural waste for the sorption of quinoline from aqueous media. A quinoline removal efficiency of around 97 % and sorption capacities of ~20 (batch) and ~35 mg g^-1 (fixed-bed) were achieved. Pseudo-second-order kinetics and Temkin isotherm best represented the equilibrium sorption data. The sorption of quinoline is exothermic and spontaneous in nature with a slight increase in the system entropy. The quinoline sorption mechanism is controlled by H-bonding, π–π dispersive interactions, boundary layer, and intraparticle diffusion. Microwave–chemical integrated regeneration technique retrieves the sorption capacity of the exhausted sorbent with 99.15, 97.64, and 95.55 % of the original, in three sorption–regeneration cycles. Energy recovery (19.365 MJ kg^-1) from the quinoline-loaded sorbent and the potential utilization of left-over ash materials enhanced the prospective of the sorbent for the remediation of pollutants for a clean and green environment.

Keywords
Fixed-bed; Intraparticle diffusion; Isotherm; Kinetics; Regeneration; Sorption