Bio-composite of chitosan and polyethylene for the biosorption of dye in wastewater

This study investigated the potential of a biocomposite adsorbent made of low-density polyethylene-chitosan nanoparticles (LDPE/CHNP) for removing Congo red and Crystal violet dyes from wastewater. Batch experiments were conducted at room temperature to study the effects of pH, contact time, initial concentration, adsorbent dosage, and temperature on the adsorption process. The results showed that the maximum sorption of Congo red and Crystal violet occurred at pH 8. The adsorption process was rapid in the first 30 minutes of contact, with more than 90% uptake, and equilibrium was achieved with 150 rpm agitation. The biosorption of Congo red and Crystal violet dyes was described using Langmuir, Freundlich, and isotherm models. The Langmuir model was found to fit the equilibrium data better, with a correlation coefficient of 0.99 and a maximal adsorption capacity of 27.1 mg/g. Based on these results, it can be concluded that the biocomposite adsorbent made of low density polyethylene-chitosan nanoparticles (LDPE/CHNP) has the potential to be an effective and abundant alternative biomass for removing these dyes from wastewater. The LDPE/CHNP biocomposite adsorbent could be applied as a remediation method for color contamination in wastewater.