Utilization ofMentha arvensiswaste biomass for the removal of Pb(II) and Co(II) from aqueous solutions

Abstract

Abstract This paper reports on the potential utility of Mentha arvensis for the removal of Pb(II) and Co(II) ions from simulated water samples. Maximum biosorption capacity value of 111.97 and 116.93 mg/g was obtained for Pb(II) and Co(II), respectively. Triton X-100-treated biomass showed remarkable increase in the biosorption capacity of biomass for Pb(II) and HCl treated for Co(II) ions, respectively. The influence of solution pH, biosorbent dose, metal ions concentration, particle size of biosorbent, and contact time on the biosorption process was also studied. Batch biosorption equilibrium data were fitted to both Langmuir and Freundlich adsorption isotherms, but the Langmuir had a better fit with the results. Reaction kinetics was best described by pseudo-second-order kinetic model. The biosorption capacity of waste biomass decreased with an increase in the temperature indicating exothermic nature of the biosorption. Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) analyses were carried out to examine functional groups and surface morphology of biomass. Results indicated that biosorption of the Pb(II) and Co(II) ions onto M. arvensis is an economical and environment-friendly method for wastewater treatment.