10.1021/acs.est.5b01652.s001 Jun Wang Jun Wang Rajamani Krishna Rajamani Krishna Jiangfeng Yang Jiangfeng Yang Shuguang Deng Shuguang Deng Hydroquinone and Quinone-Grafted Porous Carbons for Highly Selective CO<sub>2</sub> Capture from Flue Gases and Natural Gas Upgrading American Chemical Society 2015 OAC IAST Natural Gas UpgradingHydroquinone CO 2 adsorption capacity N 2 adsorption isotherms 1 atm CH scanning electron microscopy transmission electron microscopy flue gas treatment Selective CO 2 Capture adsorption separation properties 2015-08-04 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Hydroquinone_and_Quinone_Grafted_Porous_Carbons_for_Highly_Selective_CO_sub_2_sub_Capture_from_Flue_Gases_and_Natural_Gas_Upgrading/2144725 Hydroquinone and quinone functional groups were grafted onto a hierarchical porous carbon framework via the Friedel–Crafts reaction to develop more efficient adsorbents for the selective capture and removal of carbon dioxide from flue gases and natural gas. The oxygen-doped porous carbons were characterized with scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy. CO<sub>2</sub>, CH<sub>4</sub>, and N<sub>2</sub> adsorption isotherms were measured and correlated with the Langmuir model. An ideal adsorbed solution theory (IAST) selectivity for the CO<sub>2</sub>/N<sub>2</sub> separation of 26.5 (298 K, 1 atm) was obtained on the hydroquinone-grafted carbon, which is 58.7% higher than that of the pristine porous carbon, and a CO<sub>2</sub>/CH<sub>4</sub> selectivity value of 4.6 (298 K, 1 atm) was obtained on the quinone-grafted carbon (OAC-2), which represents a 28.4% improvement over the pristine porous carbon. The highest CO<sub>2</sub> adsorption capacity on the oxygen-doped carbon adsorbents is 3.46 mmol g<sup>–1</sup> at 298 K and 1 atm. In addition, transient breakthrough simulations for CO<sub>2</sub>/CH<sub>4</sub>/N<sub>2</sub> mixture separation were conducted to demonstrate the good separation performance of the oxygen-doped carbons in fixed bed adsorbers. Combining excellent adsorption separation properties and low heats of adsorption, the oxygen-doped carbons developed in this work appear to be very promising for flue gas treatment and natural gas upgrading.