The oxidation of viscose fiber optimized by response surface methodology and its further amination with PEI for CO2 adsorption

Viscose fiber was oxidized with sodium periodate to prepare a reactive dialdehyde viscose fiber (DAVF) containing abundant aldehyde groups. A solid amine adsorbent (DAVF-PEI) with high amino density for CO 2 capture was then prepared by modifying DAVF with polyethylenimine (PEI). Response surface methodology (RSM) based on a three-level, three-factorial design was used to optimize the synthesis conditions of DAVF, in which multiple linear regression equations of aldehyde content and fiber mass loss degree were constructed. The well-designed DAVF was then employed as a support to graft with PEI via Schiff base reaction to prepare a solid amine fiber (DAVF-PEI) for CO 2 adsorption. The experimental results verified that DAVF-PEI possessed good thermo-stability and high CO 2 adsorption capacity (4.11 mmol/g). DAVF-PEI also showed promising regeneration performance, which could maintain almost the same adsorption capacity for CO 2 after ten adsorption and desorption recycles.