Adsorption of methylene blue on papaya bark fiber: Equilibrium, isotherm and kinetic perspectives

Abstract

Rapid population growth and industrial expansion lead us to be habitat of a polluted planet. One of the major pollutants that badly affect the ecosystem being organic dyes released from various chemical industries where cleaner production concept is straightway adopted. Papaya (Carica papaya) bark fiber (PBF) is a natural product used for Methylene Blue (MB) dye removal as a cost-effective adsorbent from aqueous solution by batch method. Several parameters as the effect of pH, initial dye concentration, contact time, and adsorbent dosage were studied and optimized for maximum dye recovery. Reaction kinetics of the process and Langmuir and Freundlich adsorption isotherms were investigated. Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM) were used to confirm the surface properties of the PBF adsorbent. The maximum MB uptake capacity of PBF adsorbent was found to be 66.67 mg/g. Based on the results, the papaya bark fiber might be employed as a cost-effective bio-sorbent for the exclusion of dyestuffs from industrial effluent for cleaner production.