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The carbon adsorbents used for flue gas desulfurization in a moving bed reactor often suffer from serious abrasion loss, which has significantly increased the operation cost and reduced the continuous operating period. Here, we present a novel approach to reinforcing N-doped mesoporous carbons (NMPCs) by adding a small amount of N-doped carbon nanotubes (NCNTs). Compared to the undoped carbon nanotubes, the NCNTs exhibit better dispersibility in solvent and enhanced interface combination with NMPCs, which has efficiently enhanced the mechanical strength of the NCNT-NMPC composite materials. The largest fracturing strength and the best attrition resistance are obtained at a NCNT addition of 0.1 wt %. Meanwhile, the NCNT-NMPC composite delivers an average SO2 adsorption capacity of 21.2 mg/g, which is 84% higher than the undoped mesoporous carbon. Our results indicate that the defective sites introduced by N doping can help to improve the interface combination between different carbon species, and that the as-prepared NCNT-NMPC composite material is a promising high performance absorbent for flue gas desulfurization. [ABSTRACT FROM AUTHOR]

Three-dimensional individual S-doped porous red-blood-cell-like graphene (SRBCG) microspheres with double concave-surface morphology duplicated from a template-directed chemical vapor deposition process in a fluidized bed reactor not only exhibit high porosity, good structural stability, and strong anticompression properties but also present superior capacitive energy-storage abilities with respect to a symmetric supercapacitor (great compatibility at different rates) and a Li ion capacitor (no capacitance loss after 3500 cycles at 2 A g-1). The well-kept integrity of the electrode configuration after cycling benefits from the intrinsic robust scaffold which acts as a structural buffer for volume expansion to inhibit structure collapse. The unique individual microarchitecture with well-developed pore channels of SRBCG can effectively prevent the obtained graphene from aggregation or restacking, expanding the contact area between electrolyte ions and the electrode. The excellent capacitive behaviors of SRBCG are guaranteed by the unique robust microarchitecture accompanied by the good structural stability. Additionally, the fluidized bed technology is conducive to the realization of the homogeneous growth and scalable production of SRBCG. [ABSTRACT FROM AUTHOR]

Scalable synthesis of N-doped mesoporous carbons (NMPCs) and their application in flue gas desulfurization are presented. The NMPCs were prepared by carbonation of pitch powder mixed with lamellar MgO templates and melamine as N source. Both mesoporous structure and N doping have significantly contributed to enhance the SO2 adsorption rather than specific surface area. As a result, the NMPCs exhibit a sulfur capacity of 13.7 mg/g, which is twice greater than that of commercial activated carbon and 60% greater than that of the undoped mesoporous carbon. Regeneration of the NMPCs was carried out at 120°C without water vapor with good cycling stability. The NMPCs with an excellent SO2 adsorption performance are promising for application in the desulfurization process with zero emission and are especially designed for use in a refinery. [ABSTRACT FROM AUTHOR]