Development of poly vinyl alcohol (PVA) based biochar nanofibers for carbon dioxide (CO2) adsorption

The present study is focusing on the synthesis of biochar-based Poly Vinyl Alcohol (PVA) bound nanofibers through electrospinning and its CO2 adsorption capacity. Poultry litter was used for synthesizing the biochar at 300–600 °C. Synthesized biochar and fibers were characterized by Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FT-IR), and X-Ray Diffraction (XRD) to find out its morphology, composition, mass loss, functional groups, and crystalline structure. Biochar prepared at 500 °C showed rich micro-porosity. The average diameter of the nanofibers was found at 579 nm and was thermally stable up to 300 °C. The adsorption parameters under study was temperature, contact time, amine treatment, and the effect of CO2 concentration. An increasing trend was observed in adsorption capacity by increasing the contact time between the biochar nanofiber fabric and the gas and a reverse trend was prominent with increasing temperature. Keeping all other parameters constant, at 20 °C and 20 min contact time the adsorption capacity reached its maximum value of 426 mg/g. It was observed that for the same adsorption conditions the adsorption capacity of amine treated biochar-based nanofibers increased from 426 to 462 mg/g. The presence of amino groups on the surface of biochar was confirmed through FT-IR analysis.