Enhancing the formation of eco-friendly CO2 adsorbent through utilizing the RSM technique and implementation of PAN/PU electrospinning and radiation-grafted approaches

In this research, the original, efficient, novel NF-PAN/PU-GMA-EA nanocomposite was fabricated and used as an adsorbent to remove carbon dioxide from methane. For this purpose, two cheap polymers, including industrial polyacrylonitrile (PAN) and industrial polyurethane (PU) were used to prepare NF-PAN nanofibers under the electrospinning method. Then, the synthesis procedure was performed by grafting glycidyl methacrylate (GMA) onto NF-PAN nanofibers and ethanolamine (EA), diethylamine (DEA), and triethylamine (TEA) as the modified agents. In addition, the response surface methodology based on the central composite design experiments was developed to predict adsorption capacity. The aforementioned approach determined the impacts of GMA monomer (10-30%); gamma radiation at doses (10-50 kGy); and amine concentrations (40-100%). The results showed that ethanolamine was the best amine to modify the surface of NF-PAN/PU nanofibers. The highest adsorption was obtained equal to 2.95 mmol CO2/g adsorbents at a radiation dose of 28.03 kGy, 25.77% GMA and 66.45% EA. The results described that the variation from micro to nanoscale increases the adsorption capacity. Also, a significant increase in the adsorption capacity in the radiation-grafted adsorbent was observed equally to be 73.15% higher than the non-irradiated adsorbent. The adsorption capacity was decreased by about 9% after four adsorption and desorption cycles (regeneration at 80 degrees C and 15 min), indicating the proper performance of the novel eco-friendly synthesized adsorbents.