CO2 adsorption-desorption in batch and continuous conditions by using a nano-fibrous polyacrylonitrile radiation grafted adsorbent under response surface methodology

This research presents a comprehensive study on the modification of polymer nanofibers. Polyacrylonitrile nanofibers were prepared from industrial polyacrylonitrile (PAN) material using electrospinning. Then, the grafting of glycidyl methacrylate monomer on the PAN surface was successfully performed using the radiation grafting method. Also, the modification procedure was carried out using the amination approach with ethanolamine (EA). The influence of essential parameters for adsorbent synthesis, including radiation dose (10–50 kGy), monomer concentration (0–50 %), and ethanolamine concentration (0–100 %), was examined using the response surface methodology (RSM) based on the central composite design (CCD) approach. The synthesis results showed that the optimal adsorbent (NF-PAN/Rad/GMA/EA) showed a maximum bond degree (DG %) equal to 323.45 %, and a degree of amination (DA %) equal to 170.88 %. The highest adsorption capacity with NF-PAN/Rad/GMA/EA adsorbent equal to 3.23 mmol/g was obtained under ambient conditions, a flow rate of 100 ml/min, and a concentration of 5 % CO2. The highest fit was obtained with the Pseudo-second-order model in evaluating the traditional adsorption model. The Langmuir isotherm showed that the adsorption process is performed as a monolayer on the adsorbent surface. The recovery of NF-PAN/Rad/GMA/EA adsorbent at 80 °C and a low time of 15 min confirm the applicability of this novel adsorbent.