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Converting CO2 to olefins is an ideal route to achieve carbon neutrality. However, selective hydrogenation to light olefins, especially single‐component olefin, while reducing CH4 formation remains a great challenge. Herein, we developed ZnZrOx/SSZ‐13 tandem catalyst for the highly selective hydrogenation of CO2 to light olefins. This catalyst shows C2=−C4= and propylene selectivity up to 89.4 % and 52 %, respectively, while CH4 is suppressed down to 2 %, and there is no obvious deactivation. It is demonstrated that the isolated moderate Brønsted acid sites (BAS) of SSZ‐13 promotes the rapid conversion of intermediate species derived from ZnZrOx, thereby enhancing the kinetic coupling of the reactions and inhibit the formation of alkanes and improve the light olefins selectivity. Besides, the weaker BAS of SSZ‐13 promote the conversion of intermediates into aromatics with 4–6 methyl groups, which is conducive to the aromatics cycle. Accordingly, more propene can be obtained by elevating the Si/Al ratio of SSZ‐13. This provides an efficient strategy for CO2 hydrogenation to light olefins with high selectivity. [ABSTRACT FROM AUTHOR]

China's 2060 carbon neutrality goal has significant implications for energy, water, and land systems. However, the multi-sector dynamics among China's energy-water-land system have rarely been examined explicitly. This study adopts an integrated assessment framework to simulate China's energy-water-land system co-evolution under alternative carbon neutrality scenarios and climate impacts. Results show that although the net zero emission target provides the incentive for the energy system to move away from fossil fuels, total water withdrawal will increase due to the deployment of nuclear, bioenergy, and coal power plants with carbon capture and storage. Diversifying the negative emission technologies, by leveraging direct air capture technology, can alleviate the potential water stress and land use conflicts, which would otherwise be exacerbated by large-scale deployment of afforestation and bioenergy with carbon capture and storage. Northwest and northeast regions of China are the hotspots experiencing water withdrawal increases, while Bohai Rim and coastal regions are identified to experience fierce land competition. This study demonstrates the potential for general applicability to carry out resource planning and policy evaluation from the multi-sector coordination perspective. • Water-intensive electricity generation technologies drive up water withdrawal. • Diversifying negative emission technologies can reduce the impacts on water system. • Climate policy imposes more significant impacts than climate change. • Water withdrawal increases concentrate in Northwestern and Northeastern China. • Land competition mostly occurs in China's population-dense area. [ABSTRACT FROM AUTHOR]

Article 6 of the Paris Agreement enables Parties to achieve their Nationally Determined Contributions (NDCs) through direct cooperation or Internationally Transferred Mitigation Outcomes (ITMO). Current researches on Article 6 are mostly based on the assumption of unlimited global carbon market link, which may lead to large price volatility and cause concern of policy makers. In order to investigate the impact of inter-regional carbon market link mechanism on global climate action, here, we designed carbon market link scenarios with different degrees of trading volume limits. We simulated the global and regional carbon markets under different scenarios from 2025 to 2060 using the Global Change Assessment Model (GCAM). The findings suggest that as the link limit tightens, both the price volatility of global carbon market and the cumulative mitigation costs saved by carbon market links decrease, which reminds policy makers of the trade-off between economic efficiency and price volatility. The price volatility under the unlimited global carbon market scenario is about 30% higher than that with link limits implemented, while the unlimited market would also save about 0.83 trillion dollars abatement costs than the limited scenario. At the national level, a total of 14 regions are limited in different link limit scenarios, among which China, the United States, EU and India are the most sensitive regions to link limits. Based on the scenario results, we discuss the design of international carbon market link mechanisms, such as absolute link limits and relative link limits. • A trade-off between economic efficiency and price volatility under link limit. • A total of 14 regions are limited in the limit scenarios. • China, U.S., EU and India are the most sensitive regions to link limits. • Regional heterogeneity in sensitivity to absolute and relative limit mechanisms. • The direction of the financial flows remains unchanged with link limits. [ABSTRACT FROM AUTHOR]

After China's Carbon Peaking before 2030 and Carbon Neutrality before 2060 targets announced, there is strong need to figure out transition pathways in some industrial sectors which is difficult to make deep cut of CO 2 emission. This study make effort to present feasibility of zero carbon production and transition roadmap for China's ammonia industry. By using IPAC-technology model, this study compiled the production technologies, in-effect policies, and projects-in-pipeline of the ammonia industry, to figure out various technology pathways in sector, explored high/medium/low solar LCOE scenarios, and investigated the impacts of carbon price policy on the transition pathway. From this study we could see that China's ammonia industry carbon emissions peak before 2020 and it is possible to achieve net zero emissions by 2050. The results also indicated that all zero-carbon transition technology pathways could be identified over four periods from 2020 to 2050 and electrolysis technology could dominate ammonia supply and help to achieve zero carbon production as early as 2038 in the low LCOE scenario. The production costs output from our model showed that zero-carbon ammonia could be cheaper than conventional ammonia as early as 2030. Even in the high LCOE scenario, ammonia price could be 562 yuan/tNH 3 , which is much lower than current price, 2652 yuan/tNH 3. Carbon price policy has small effect in the transition. All our preliminary results supported the formulation of clean production and sustainable development measures and policies for the ammonia industry in China. [Display omitted] • The ammonia industry would achieve carbon neutral before 2050 in China. • CO 2 emissions of China's ammonia industry peak before 2020. • Both PEM and HTGC are crucial for the decarbonization of the ammonia industry. • There is a tradeoff between the timing and cost efficiency in the decarbonization. • Carbon price policy has limited effect. [ABSTRACT FROM AUTHOR]