Polyethylenimine-aminated polyvinyl chloride fiber for adsorption of reactive dyes from single and binary component systems: Adsorption kinetics and isotherm studies

Abstract

In this study, a polyethylenimine-aminated polyvinyl chloride fiber (PEI-PVCF) was prepared, which exhibited excellent adsorption properties for Reactive Black 5 (RB5) and Reactive Orange 16 (RO16) from single- and binary-component systems under neutral conditions. The pH edge, kinetic, isotherm, and thermodynamic experiments were conducted to evaluate the adsorption performance of PEI-PVCF for RB5 and RO16. The effect of coexisting ions on the removal of reactive dyes by PEI-PVCF was also investigated. The regeneration experiment was performed to evaluate the reusability of PEI-PVCF for reactive dyes removal. The results were as follows: The PEI-PVCF showed high removal efficiency for RB5 and RO16 in a wide range of pH (2−8). Kinetic modeling suggested that chemisorption plays an essential role in the adsorption process. The intraparticle diffusion model revealed that intraparticle diffusion was not the only rate-controlling step. The isotherm models showed that the adsorption of PEI-PVCF for RB5 and RO16 was monolayer adsorption, and the PEI-PVCF had a higher affinity for RB5 than RO16. The maximum adsorption capacities of PEI-PVCF for RB5 and RO16 calculated by the Sips model were 1265.0 and 1171.5 mg/g in single-component systems, and 932.3 and 473.4 mg/g in binary-component systems, respectively. Thermodynamic experiments results revealed that the adsorption process was exothermic. The adsorption mechanism study revealed that electrostatic interaction and H-bonding were the main mechanisms involved in the adsorption process. The inhibition effect of coexisting ions on the adsorption of RO16 by PEI-PVCF was more significant than that on RB5. In addition, the reusability study depicted that the PEI-PVCF can be reused at least five times. These results indicated that the PEI-PVCF has good potential in industrial applications.