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Achieving excellent efficiency to mineralize volatile organic compounds (VOCs) under nonthermal plasma catalysis (NTP-catalysis) systems tremendously relies on the catalyst design. Herein, we report a dual-template strategy for synthesizing a core–shell structured nitrogen-enriched hollow hybrid carbon (N-HHC) by a facile pyrolysis of a Mn-ZIF-8@polydopamine core–shell precursor. N-HHC exhibits a remarkable plasma synergy effect and superior degradation efficiency for toluene (up to 90% with a specific input energy of 281 J/L), excellent CO2selectivity (>45%), and byproduct-inhibiting capability. Such outstanding functionality of the developed N-HHC is uniquely attributed to its hollow multistage and channeling structure, high concentration of O3-decomposing species (pyrrolic and oxide pyridinic-N), and abundant ZnO active sites. Shedding light on an efficient synthetic strategy for designing an advanced nanocatalyst with enhanced VOC destruction in the NTP-catalysis system, the present results could be extended to design other N-doped metal/metal oxide-decorated hollow porous carbons for environment-related applications.

Non-vanadium-based catalysts with high SO2tolerance are still interesting in selective catalytic reduction of NO by NH3(NH3-SCR) and SO2adsorption is the foremost step for the deactivation of catalysts. In order to alleviate the adsorption of SO2, we fabricated a series of rhenium (Re; without stable sulfate) supported TiO2catalysts and studied their SO2tolerance for the first time. Owing to suitable surface acidity and reducibility, ReOx/TiO2catalysts exhibited satisfactory activity in a wide temperature range of 250–350 °C. As expected, experimental results and DFT calculations indicated that SO2adsorption on ReOx/TiO2catalysts was rather weak, thus the catalysts performed excellent SO2tolerance in the NH3-SCR reaction. Moreover, in situDRIFTS indicated that the NH3-SCR reaction on ReOx/TiO2catalysts followed the Eley–Rideal mechanism and SO2had little effect on the reaction mechanism. Our findings should provide new insights into the development of SCR catalysts with high SO2tolerance.

In the present work, a series of MOF-74 (Ni) materials with narrow micropore channels and abundant unsaturated metal sites was respectively prepared via hydrothermal (HT), condensation reflux (CE), and microwave-assisted (MW) methods. The physicochemical properties of synthesized materials were characterized by powder X-ray diffraction, N2-sorption, field-emission scanning electron microscopy, Fourier-transform infrared (FTIR), thermogravimetric (TG)/TG-FTIR, X-ray photoelectron spectroscopy, UV–vis–near infrared, NH3/CO2-temperature programmed desorption, and in situdiffuse reflectance infrared Fourier transform spectroscopy. Their CO2/N2adsorption performances were evaluated by isotherm adsorption and dynamic adsorption experiments. We found that the MW is a rapid and facile protocol for the synthesis of MOF-74 (Ni) materials with highly efficient CO2capture capacity. The well-shaped MW-140 adsorbent with superior CO2adsorption capacity of 5.22 mmol/g at 25 °C can be obtained within 60 min by the MW process, almost 6 times higher than that of the commercial activated carbon (0.89 mmol/g). Results of dynamic adsorption experiments showed that the MW-140 material possesses the highest CO2adsorption capacity of 3.37 mmol/g under humid conditions (RH = 90%). Importantly, MW-140 has excellent adsorption stability and recyclability, superior CO2capture selectivity (CO2/N2= 31), and appropriate isosteric heat in CO2adsorption (21–38 kJ/mol), making it a promising and potential material for industrial CO2capture. Characterization results demonstrated that the high capture capability of MOF-74 (Ni) materials can be attributed to the synergistic effect of abundant narrow micropore channels and rich five-coordinated Ni2+open metal sites which are beneficial for the trapping of CO2molecules.

Due to the extremely low permeability of shale formations, the combination of horizontal well and volume fracturing has been proposed as an effective technique to improve the production of Dagang continental shale oil reservoirs. Based on the flow material balance method (FMB) and straight-line analysis (SLA) method, the stimulated reservoir volume (SRV) and drainage volume are determined to identify the flow regimes of the seepage mechanism of shale oil reservoirs. To resolve the challenges of multi-scaled flow regimes and bottom hole pressure (BHP) variation before and after pumping in shale oil wells, a multi-linear analytical flow model was established to predict the future production and the final expected ultimate recoverable oil (EURo) after fitting the historical production dynamics. Based on the results, it can be concluded that the flow regime of a shale oil well in production can be divided into two stages consisting of linear flow within SRV and composite flow from the un-stimulated area to SRV. The effects of fracturing operation parameters, such as fracturing fluid volume and sand/liquid ratio, on shale oil productivity, are analyzed, and insightful suggestions are drawn for the future development of this pay zone.