In this study, the modified activated coke (AC-Tit) was prepared from coals using titanium ore by the blending method with a one-step carbonization–activation process. The results show that the addition of titanium ore affects the physicochemical properties of AC-Tit. The AC-Tit samples have higher V mic and V mic/V tot ratios as well as oxygen and CO functional group. The metal oxides (i.e., FeTiO3, TiO2, Fe2O3, and Fe) were detected on the surface of samples, attributed to the existence of Fe and Ti in the titanium ore. The titanium ore addition improved the desulfurization performance of the AC-Tit effectively; the highest sulfur capacity was 203.3 mg/g, which was much higher than that of the blank sample (120.1 mg/g). After desulfurization, some metal sulfates, i.e., Fe2(SO4)3 and CaSO4, were detected on the AC-Tit samples. When the sample was regenerated, its surface area (S BET) and V mic did not change significantly, the relative content of CO decreased, and COOH increased evidently. In addition, metal sulfates on the AC-Tit samples were not decomposed during the regeneration process. The variation of surface chemical properties of the regenerated AC-Tit caused the reduction of the desulfurization activity after regeneration.

The regeneration properties of a novel pyrolusite-modified activated coke (ACP) by blending method were investigated. Cyclic regeneration of ACP (ACP-Rn) shows the ACP was a good desulfurizer. The sample had the best desulfurization performance after five regeneration cycles (ACP-R5), and its sulfur capacity was 178 mg/g, 10.8% higher than that of ACP (161 mg/g). The S BET and pore volume were increased with the number of regeneration cycles, but they were not the limiting factors of the SO 2 removal. The better surface functional groups, especially the basic sites, contributed more to the improvement of desulfurization performance of ACP-Rn. The loaded metals played an important role in SO 2 removal. The accumulation of metal sulfate in ACP rapidly increased from the first to fifth regeneration cycles and then remained relatively stable during further reuse. The ACP regeneration process divided into three stages: drying, reaction, and pyrolysis. The wrapped metals relatively enhance the pyrolysis and acted as further surface modifications.

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The stumbling block to the ever-increasing need for improving air quality remains nitrogen oxides (NO x ). The copper-introduced Ce/CAC-CNT (Cu x Ce/CAC-CNTs) catalyst using the in situ-growth-prepared activated carbon and carbon-nanotube composite (CAC-CNT) carrier with high sulfur dioxide tolerance was successfully applied to low-temperature NH3–SCR in this study. The findings indicate that the Cu x Ce/CAC-CNTs obtained at a 0.2 Cu/Ce molar ratio and the calcination temperature of 450 °C showed the highest 100% NO conversion with 95.8% N2 selectivity at 150 °C and 10 000 h–1. The incorporation of Cu improved the Cu0.2Ce/CAC-CNTs in Lewis acid, lattice oxygen (31.99%), and Ce3+ (26.03%). The accelerated NH3 adsorption on acid sites, the encouraging electron transfer by the Ce4+ + Cu+ ↔ Ce3+ + Cu2+ redox circle, and the more surface chemisorbed oxygen (Oβ) improved the catalytic activity of Cu0.2Ce/CAC-CNTs. The NH3–SCR of Cu0.2Ce/CAC-CNTs largely follows the L–H mechanism, together with a certain degree of “Fast SCR.” The added Cu species effectively prevented surface SO2 adsorption and oxidation, and the Cu0.2Ce/CAC-CNTs restored more than 94% SCR activity after 8 h of poisoning in 50 ppm SO2 and 5 vol % H2O.

A Ce-supported activated carbon-carbon nanotube composite (Ce/AC-CNTs) catalyst was prepared by in situ formation of CNTs on AC and then modified by Ce, and was subsequently used for low-temperature selective catalytic reduction of NOx with NH3.

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Multifunctional polymers have wide applications in smart materials. In this study, the multifunctional polymer (hydrophilic graphene‐Fe3O4‐PVA, GFP composite films) were synthesized by mixing with hydrophilic graphene (HG), ferrous ammonium sulfate, and ferric chloride in PVA solution through one‐pot coprecipitation method. GFP composite films were characterized by XRD, FT‐IR. Their morphology and particle size of Fe3O4 in GFP composite film were observed by TEM, SEM, and AFM. The results indicated that the morphology of Fe3O4 in GFP could be modulated from sphere shape to rod structure by the loading quantity of HG. Besides, many properties of GFP composite films were investigated. Firstly, GFP composite films demonstrated the fast magnetic response and high thermal stability. Secondly, the introduction of HG not only simultaneously enhanced the stiffness and ductility of GFP composite films, but also improved their flame retarding performance. Finally, HG regulating effect for the morphology of Fe3O4 in GFP and improvement mechanism of HG for mechanical performance of GFP composite films were illustrated. Both of them might be contributed to the hydrogen bonds effect among Fe3O4, PVA, and HG. Thus, these multifunctional GFP composite films can be applicable as the basis of fabricating smart materials in different fields. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48174.