Effective synthesis route of renewable nanoporous carbon adsorbent for high energy gas storage and CO2/N2 selectivity

Mandarin peels are fruit by-products and provide an economically viable and renewable carbon source. In order to recycle and convert the bio-waste materials, a scalable synthesis approach for mandarin peel-derived porous and activated carbon were designed, and an influence of its preparation conditions such as carbonization, activation temperatures and activating agents was well investigated. The developed nanoporous carbon achieves high textural properties of surface area of ∼2500 m2 g−1 and pore volume of 1.04 cm3 g−1 and is naturally doped by sulphur. Owing to a high textural properties and some metal residues, obtained nanoporous carbon exhibited promising sorption properties for all energy carrier gases (e.g. H2, CH4) and excellent CO2 separation and storage performance, that to the best of our knowledge are among the highest reported values for porous carbons. The H2 storage capacities at 77 and 298 K and 25 bar were recorded as 6.1 and 0.45 wt%, respectively. For CH4 and CO2 storage at 298 K and 25 bar, uptake of 9.65 and 20.6 mmol g−1 were achieved, respectively. Additionally, the separation of various binary mixtures (CO2/CH4, CH4/N2 and CO2/N2) at different composition was studied according to the ideal adsorbed solution theory (IAST) model and a high value of 63 was achieved for CO2/N2 which is among the top values for nanoporous carbons reported in the literature.