Effect of heat treatment temperature on CO₂ capture of nitrogen‐enriched porous carbon fibers

Abstract

Porous carbon fibers (PCFs) were prepared from porous polyacrylonitrile fibers by cross-linking, oxidation, and carbonization. X-ray diffraction patterns revealed that graphite structures as well as disordered carbon coexisted in the PCFs. Nitrogen content was more than 15.3 wt% with the variation of oxidation temperature, and a maximum value was obtained at 275°C. Nitrogen was quickly released with carbonization temperature. Compared with the fiber prepared at elevated carbonization temperatures, those owning high nitrogen contents deserved better carbon dioxide (CO 2 ) adsorption performance in the simulated flue gas environment (10% CO 2 /90% N 2 ). The CO 2 adsorption had a better relationship with nitrogen content rather than specific surface area and pore volumes. Especially, nitrogen was very useful to enhance the CO 2 adsorption of the fibers with low microporosity. The heat of CO 2 adsorption was in the range of 39.8-54.6 kJ mol −1 , which indicated good selectivity of CO 2 adsorption. C

Oxygen and nitrogen enriched pectin-derived micro-meso porous carbon for CO2 uptake

“…Nitrogen-containing groups, also including Lewis bases, are known to be active sites for acidic CO 2 binding. [20][21][22] Many research has been published on the effect of oxygen-containing groups on CO 2 adsorption. A study by Dawei et al detected the interactions between CO 2 and oxygen functional groups were stronger than the interactions between CO 2 and carbon surface.…”

“…Precursors can be typically divided into two specific categories: natural and synthetic. Through various synthesis methods, porous carbons are traditionally obtained by pyrolysis of a variety of C-rich materials as precursors, which can be synthetic (formaldehyde, 26 resorcinol, 27 and thiourea 28 ) or natural (biomass, cheap agricultural, and materials with known chemical composition) such as pine cone, 29 chitosan, 21 and poplar wood. 30 Pectin is a low-cost natural polysaccharide and contains a linked α- d -galacturonic acid backbone with many hydroxyl and carboxyl groups.…”

Hierarchical Porous Activated Carbon from Wheat Bran Agro‐Waste: Applications in Carbon Dioxide Capture, Dye Removal, Oxygen and Hydrogen Evolution Reactions

“…In addition, an abundance of micropores also provides favorable and more efficient paths for high-performance adsorbent. [42] Figure 2c shows the N 2 adsorption-desorption isotherms and the pore size distribution (Figure 2d) of the synthesized carbon materials at 77 K. As illustrated in Figure 2d, WB-RC exhibits a type I adsorption isotherm at a swift curve at low relative pressure, suggesting the homogenous microporous structure. However, WB-AC is classified as type IV, along with a slight H4 hysteresis loop, which indicates the characteristic mesoporous nature, according to IUPAC.…”

Nitrogen-Containing Porous Carbon Fibers Prepared from Polyimide Fibers for CO2 Capture

“…As for both of the fibers, the amount of N 2 adsorbed is distinctly lower than that of CO 2 adsorbed at the same temperature and partial pressure. CO 2 /N 2 selectivities of ACF-800 and UCF-800 are obtained by utilizing the virial equation, , and the Henry’s law selectivity is calculated as previously described . The virial characteristic curves are shown in Figures S4 and S5, and Henry’s law constants for CO 2 and N 2 are shown in Table S2.…”