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Light hydrocarbons are competitive novel energy sources and are expected to be alternatives to traditional fossil fuels. However, the leakage of unburned light hydrocarbon molecules in industrial applications would cause serious environmental problems, which limits future development and application of this novel energy source. Therefore, the removal of unburned light hydrocarbon molecules received extensive attention. The catalytic combustion technology is widely applied to their removal due to its economy, low energy consumption, high removal efficiency, mild reaction process and non-toxic and harmless product. This paper summarizes the research progress in catalytic combustion of light hydrocarbons over the past decade and its future challenges. It discusses systematically the different types of catalysts employed for catalytic combustion of light hydrocarbons in recent years and summarizes objectively their superiority and deficiency in catalytic applications. Subsequently, the reaction mechanism of catalytic combustion of light hydrocarbons and the characteristics of catalysts for different reaction mechanisms are discussed. Then, the structure–activity relationship of the catalysts for catalytic combustion of light hydrocarbons is concluded and discussed intensively. Finally, the prospect is presented for the rational design of efficient catalysts for catalytic combustion of light hydrocarbons, insight into the reaction mechanism and the development of characterization techniques. [ABSTRACT FROM AUTHOR]

SO2 poisoning is a common problem in the catalytic combustion of volatile organic compounds (VOCs). In this work, we took three-dimensionally ordered macroporous and mesoporous (3DOM) SiO2 as the nanoreactor to protect active sites from SO2 erosion in the catalytic combustion of benzene. Simultaneously, the confined growth of metal active nanoparticles in the multistage pore is also full of challenges. And we successfully confined Co3O4 nanoparticles (NPs) in macroporous and mesoporous channels. Interestingly, the precursors' growth in the pore was controlled and nanoreactors with different pore sizes were prepared by adjusting the loading amount and preparation methods. It is discovered that the Co3O4 NPs confined in 3DOM SiO2 nanoreactor showed superior sulfur and water resistance. Density functional theory (DFT) calculations verified that the Co-Si catalyst had high SO2 adsorption energy (−0.48 eV), which illustrated that SO2 was hard to attach to the surface of the Co-Si catalyst. The SiO2 nanoreactor had low SO2 adsorption energy (−5.15 eV), which indicated that SO2 was easily absorbed on SiO2 nanoreactor. This illustrated that the SiO2 nanoreactor could protect effectively active sites from SO2 erosion. [ABSTRACT FROM AUTHOR]

This study for the first time proposed two kinds of chemical modification approaches to promote the uniform and stable growth of MOFs on PAN nanowires. Acid hydrolysis was performed to form some carboxylic acid groups on the surface of PAN nanowires, and an ammonia process was used to enhance the coordination ability of PAN with metal ions. Through the modulation of the coordination environments, ZIF/H–PAN and ZIF/NH–PAN showed big differences in morphology and chemical properties. The bead-like dodecahedron H–Co3O4 catalyst derived from the bead-like ZIF/H–PAN showed excellent activity for the catalytic combustion of VOCs. [ABSTRACT FROM AUTHOR]

Oxidative dehydrogenation (ODH) of 1-butene with CO 2 to 1,3-butadiene (BD) via Fe-based catalysts is a promising strategy, and the mobility of lattice oxygen plays a key role in the catalytic reaction. However, the catalytic activity of Fe-based catalysts is limited by the poor lattice oxygen mobility. To improve the mobility of lattice oxygen and optimize the ODH reaction, a series of 3DOM Fe-based catalysts (FeVAlO x , FeCrAlO x , and FeVCrAlO x ) were prepared by PMMA template method. Among these samples, the multi-component FeVCrAlO x samples showed the best catalytic activity, and the 1-butene conversion of the multi-component catalyst could reach 88.3%, the BD yield could reach 27.5%. Further study found that the introduction of multi-component elements (V and Cr) not only promoted the formation of the γ-Fe 2 O 3 phase but also formed more active components (V 5+ and Cr 6+ ). More importantly, the lattice oxygen mobility was also significantly improved. In addition, the reaction in the presence of water conditions was studied by activity tests and in situ DRIFTS tests. The results show that CO 2 was present in the form of HCO 3 - . The utilization of CO 2 was improved and the reaction path was changed.

A noble metal catalyst shows excellent low-temperature oxidation activity in the catalytic combustion of benzene but has the problem of SO 2 poisoning. We all know that SO 2 easily competes with the reactant molecules for adsorption of the active site and has electronic effects on the active site to deactivate the catalyst. Therefore, the sulfur resistance of catalysts is the key problem to be solved in the process of catalytic combustion of benzene. Herein, the Pt/SiO 2 catalyst with an ordered mesoporous structure was prepared by a one-step hydrothermal method, and MgO, ZnO, and MnO x were, respectively, coated on the surface of Pt/SiO 2 as ultrathin shells to improve the sulfur resistance of Pt/SiO 2 . We observed that the sulfur resistance of the Pt/SiO 2 catalyst was significantly improved due to the protective effect of the metal oxide shell. By comparing the three core-shell catalysts, it was found that the Pt/SiO 2 @MnO x catalyst coated with a MnO x shell had the best performance. The reason was that the MnO x shell not only protected the Pt active site but also had a good electron transfer effect on the core Pt, so it could effectively avoid the rapid adsorption poisoning of SO 2 on the active Pt 0 site. In addition, it was verified that the excellent redispersion of MnO x species in a SO 2 atmosphere could increase the low-temperature oxidation activity of the Pt/SiO 2 @MnO x catalyst. Meanwhile, in situ DRIFT results also confirmed that the MnO x shell could significantly promote the oxidation of benzene molecules in the SO 2 atmosphere.

This study for the first time proposed two kinds of chemical modification approaches to promote the uniform and stable growth of MOFs on PAN nanowires. Acid hydrolysis was performed to form some carboxylic acid groups on the surface of PAN nanowires, and an ammonia process was used to enhance the coordination ability of PAN with metal ions. Through the modulation of the coordination environments, ZIF/H-PAN and ZIF/NH-PAN showed big differences in morphology and chemical properties. The bead-like dodecahedron H-Co 3 O 4 catalyst derived from the bead-like ZIF/H-PAN showed excellent activity for the catalytic combustion of VOCs.