چكيده به لاتين
A green self-activating synthesis system has been introduced for the porous carbons. This system was used for the synthesis of hierarchical porous carbons from celery wastes. The activating reagents were gases released during the pyrolysis treatment, resulting in the synthesis of porous carbons without using any extra activator. Based on the adsorption desorption results, the optimal porous carbons were synthesized at 700 °C, providing surface area as high as 1126 m2g-1 and micropore volume of about 0.7 cm3 g-1. X-ray Photoelectron Spectroscopy indicates the presence of graphitic nitrogen in the porous carbon structure. The synthesized porous carbons were applied for CO2 capture. CO2 adsorption test was performed at low and high pressures and several temperatures. Under low pressure (0-1 bar), this sorbent adsorbed 5 mmolg-1 at 0 °C and 2.03 mmolg-1 at 25 °C. Moreover, at high pressures adsorption isotherm and kinetic models at 298 °K and 9.5 bar, the fitted Langmuir isotherm with the highest adsorption potential was found to be 9.57 mmolg-1. The physisorption process was reported by enthalpy 23.2 kJ.mol-1 and the Fractionalorder kinetic model was found to be the best match in the kinetic curves. The sample exhibited stable CO2 adsorption in ten cycles, showing the high reusability for CO2 capture. Eventually, the technology described herein presents a promising strategy for producing ecofriendly porous carbon from other biomass wastes on the industrial scale.
