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China has put forward the "Dual Carbon" target, carbon peak by 2030 and carbon neutrality by 2060. It is necessary to study the current situation of carbon emissions, carbon reduction potential, and decarbonization paths of industrial cities in China. Taking Wuhan, a typical industrial city, as an object, anthropogenic carbon emissions and distribution in Wuhan in the last 20 years are analyzed. The extended STIRPAT and the gray relation models are adopted to construct a decomposition model for discerning the driving factors of carbon emissions in Wuhan. Besides, a scenario-driven carbon emission projection system with five development scenarios is established, where carbon sinks from the ecosystem and CCUS technology and the decoupling status of “CO2emissions-GDP” are considered, to assess Wuhan's carbon emissions reduction potential and decarbonization pathways by 2060. The results show that Wuhan's carbon emissions mainly come from the industrial and transportation sectors and that the increase in the share of tertiary industry and the decrease in carbon intensity are the main factors curbing Wuhan's carbon emissions. To realize the “Dual Carbon” target, Wuhan's decarbonization development should start with the ISI (Industrial Structure improving) scenario and focus mainly on the development of tertiary industry between 2022 and 2035. Between 2035 and 2045, the decarbonization development transitions to the BID (Comprehensively improving) scenario, which requires simultaneous accelerating improvement of the city's economy and energy structure. Finally, carbon neutrality can be achieved between 2050 and 2060 through ecosystem carbon sinks and technology carbon sinks.

•Copper nitrate salt got pyrolysis on CeO2to form the Cu/CeO2catalysts.•Cu/CeO2-400 catalysts get the best CO production rate at 1.23 mol/gcat.h at 400 °C.•Cu-O-Ce interaction induced more vacancy formed in the Cu-CeO2interface.•Oxygen vacancy formed in the Cu-CeO2interface enhanced CO2hydrogenation.

During oxy-fuel combustion, the NO emission can be inhibited by the strongly reductive atmosphere caused by the high proportion of gasification reaction, which is a unique feature that differs from air combustion. The alkali and alkaline earth metals (AAEMs) contained in coal ash can catalyze gasification reactions, promoting the homogeneous reduction process of NO. Besides, AAEMs also suppress NO emission through catalyzing the NO heterogeneous reduction by char (C-NO). Both catalytic effects of AAEMs have been studied at relatively low temperatures (below 1000°C) in a simple atmosphere (pure CO2). However, the catalytic effect of AAEMs on NO reduction is still unclear during oxy-fuel combustion due to the more complex reaction atmosphere, higher reaction temperatures, and the presence of gasification reactions. In this work, the effect of different factors on the catalytic effect of AAEMs under O2/CO2atmosphere is investigated. Results show that the order of the catalytic effect of AAEMs on NO reduction is Na> K> Ca> Mg, with the highest NO reduction efficiency of 30% for Na. The catalytic effect of Na on NO reduction weakened as the temperature increases. When the temperature increased from 1373 K to 1573 K, the NO reduction efficiency (ηNO) of Na decreased from 30% to 6%. While the catalytic effect of Na on NO reduction strengthened as the oxygen concentration increases. When the O2concentrations increased from 10 vol.% to 30 vol.%, the ηNOvalues of Na increased from 27% to 35%. The K-Na binary additive is more effective in reducing NO emissions than K and Na alone, with NO reduction efficiency as high as 46.8% at a K/ Na is 1:2. Besides, the Raman test results reveal that K contributed to the conversion of amorphous carbon into a regular graphite crystal structure. Na disrupted the graphite structure resulting in more defective points appearing in the graphite lattice. These results are expected to provide a theoretical reference and new insights for the reduction of NO emission during oxy-fuel combustion.

•Competitive adsorption of CO2and SO2on CaO-based sorbents was studied•NaBr enhanced the CO2capture capacity of the CaO-based sorbents•NaBr enhanced the SO2capture capacity of the CaO-based sorbents•Fractal theory was applied to analyze the mechanism of NaBr promotion•“NaBr/CaO” captured threefold of CO2than “CaO, AR” over the 50 cycles