Greenhouse Gases: Science and Technology最新文献

One of the most essential features of an oxygen carrier is its ability to be oxidized and reduced in order to transfer oxygen in a chemical looping system. A highly reduced oxygen carrier can experience multiple performance issues, such as decreased reactivity, agglomeration, and defluidization. This is crucial for processes that require limited oxygen transfer from the air reactor to the fuel reactor. Meanwhile, biomasses as environmentally friendly fuel options contain ashes, which would inevitably react with oxygen carriers and exacerbate the performance issues. To mimic the interactions between a highly reduced oxygen carrier and biomass ash compounds, four iron-based oxygen carriers, based on natural ores and waste materials, and three potassium salts, K₂CO₃, KH₂PO₄, and K₂SO₄, were investigated in a tubular reactor under an atmosphere consisting of 2.5% H₂ and 10% steam in Ar and N₂ at 900°C for 3 h. The results from the X-ray diffraction (XRD) material analysis showed that both initially fully oxidized and highly reduced materials reach the same oxidation state after the experiment. Based on the scanning electron microscopy coupled with energy dispersive X-ray spectroscopy results, K from K₂CO₃ and K₂SO₄ diffuses in the oxygen carrier particles, while K from KH₂PO₄ always forms a distinct layer around the particles. The initial oxidation state of an oxygen carrier surface affects the interactions with the potassium salt only to minor extents. Thus, the final state of the material and its performance in a large-scale process are only occasionally and mildly affected by its initial oxidation state. © 2023 The Authors. Greenhouse Gases: Science and Technology published by Society of Chemical Industry and John Wiley & Sons Ltd.

Catalytic thermal hydrogenation of CO₂ to CH₄ is one of the promising decarbonization technologies, and Ru is considered to be the most active metal for low-temperature CO₂ methanation. In this work, a series of metal-promoted Ru-based catalysts were prepared by the impregnation–precipitation method. The catalyst composition, reduction temperature, reaction gas concentration, and reaction conditions were optimized. The reaction mechanism was investigated through CO-DRIFTS experiments. It was found that the addition of Pt could promote the adsorption of CO on the surface of ruthenium-based catalysts, which was beneficial to the methanation reaction. In addition, in situ DRIFTS experiments observed surface species of catalysts during the reaction, and it was concluded that bicarbonate was the intermediate species of the reaction. © 2023 Society of Chemical Industry and John Wiley & Sons, Ltd.

Copper is the primary material of the national manufacturing industry, widely used to construct the national economy. As one of the critical minerals, trade security of copper resources is related to the stable development of the domestic industry. The dynamic evaluation of China's copper trade and identification of the principal risk points is helpful to promote the sustainable development of resources. In this paper, the environmental impact of trade is included in the research category, and the paper conducts a dynamic assessment of China's copper trade risks from 2001 to 2020 of multiple dimensions through the improved DEA-like model, identifies the main risk points in different periods, and predicts future trade risks. The results show that China's copper resource trade risk has continued to rise since 2001, and its characteristics have gradually changed. The main risk points of trade have experienced the market equilibrium stage, reserve resources stage, and import dependency stage. A high degree of external dependence and environmental pollution intensification has become the key factors influencing the trade risk at the present stage. Copper resources risk will rise slowly in the future and reach a high-risk state. Trade risks will decline slightly after 2025, but it is still in a dangerous condition. Relevant policies need to be issued to alleviate the trade risk. Combined with the evaluation results, this paper puts forward multidimensional risk management suggestions to ensure the security of copper resources, and improve the flexibility of the resource industry chain. The article provides direction for resource security and sustainable development in the future. © 2023 Society of Chemical Industry and John Wiley & Sons, Ltd.

The objective of this study was to investigate the transport and fate of CO₂ injected into a sandstone reservoir in the western Farnsworth Unit, a hydrocarbon field in northern Texas. The study employed three-dimensional multifluid-phase numerical reactive solute and heat transport modeling. Model inputs were obtained from previous field characterization studies and calibrated to 8 years of historical production data. The CO₂ in the models was injected through multiple wells for the first 25 years of the simulations according to a water-alternating gas schedule. The simulations were carried out for a total of 1000 years in order to study the long-term effects of CO₂ injection.

The results show that the largest fraction of the injected CO₂ is stored in oil, followed by successively smaller amounts in the formation water, carbonate mineral phases, and as an immiscible gas phase. The small fraction of CO₂ present as an immiscible gas, the most mobile phase for CO₂, aids in the long-term sequestration security of the injected CO₂. The injected CO₂ was found to migrate within a maximum radius of around 500 m of the injection wells. This means that changes in fluid pressure, temperature, composition, and reservoir mineralogy were also limited to occurring within this radius. This radius is very sensitive to model relative permeability and capillary pressure values, which were determined from history matching to the field production data. The models predicted dolomite to be the main mineral sink for the injected CO₂. Quartz was another mineral predicted to precipitate, whereas calcite, albite, chlorite, illite, and kaolinite were predicted to dissolve. The changes in mineral abundance had minimal effect on porosity, implying that the permeability of the reservoir should also not change much because of CO₂ injection. © 2023 Society of Chemical Industry and John Wiley & Sons, Ltd.

This study demonstrates a continuous method for the production of high-quality ZIF-8 and HKUST-1 (surface areas over 1500 m²/g) under mild synthesis conditions (ambient pressure and temperatures below 100°C) with only environmentally preferable green solvents (water and ethanol) being used in the entire synthesis process. High yields of metal organic frameworks (MOFs) are achieved (65% for ZIF-8 and 79% for HKUST-1). The comparison between the as-synthesized samples and commercially available equivalents with respect to shape, size, surface area, thermal stability and CO₂ uptake capability was conducted in this research. The synthesized MOFs both show competitive CO₂ adsorption ability under a pressure in the range of 1–5 bar. Under a pressure of 5 bar,CO₂ uptake capacity of ZIF-8 and HKUST-1 is 3.83 mmol/g and 6.68 mmol/g, respectively, which are 3.81 mmol/g and 6.62 mmol/g, respectively, for commercialized samples. The synthesized HKUST-1 has higher values compared to the commercialized one within this range of pressures. This indicates the method developed in this study is promising to to be used for the continuous production of high-quality MOFs for CO₂ capture applications. © 2023 The Authors. Greenhouse Gases: Science and Technology published by Society of Chemical Industry and John Wiley & Sons Ltd.

Rock burst disasters can be reduced and prevented with the help of coal dust water injection. In this study, the high-pressure water injection device is used to examine how the water absorption rate changes over time under various water injection pressures. The results reveal that the water absorption rate of coal samples increases quickly initially before slowing down with water absorption time. Its change can be described using the Langmuir equation. In addition, the Langmuir equation is utilized to demonstrate how water injection pressure affects the maximum water absorption of coal samples. The effects of experimental findings and numerical analysis are investigated on water injection pressure. The breadth and extent of coal bodies with increased moisture are continuously expanding at the same water injection pressure and water injection time. The water absorption of coal close to the borehole remains relatively unchanged with an increase in water injection pressure, but the water absorption range of coal in the vicinity increases. Therefore, raising the water injection pressure and duration will improve the effective range of water injection. © 2023 Society of Chemical Industry and John Wiley & Sons, Ltd.

Carbon capture and storage (CCS) has been highlighted as a crucial technology for reducing carbon emissions, yet CO₂ leakage from the reservoir is still a matter of great public concern, especially because of water pollution reasons. Hence, reduced-scale CO₂ release experiments have been conducted worldwide to study hydrogeochemical response in shallow groundwaters. Although other reviews have been previously published, this study reviews critical data to establish a geochemical process-based framework of the scientific findings. Following this, four mechanisms were found to be responsible for hydrogeochemical behavior: (i) ion exchange is mainly responsible for short-lived increase in Mg, Ca, Ba and Sr concentrations; (ii) sorption and desorption processes were related to heavy metal and trace element variations, seemingly due to the presence of oxyhydroxides and clay minerals; (iii) silicate and carbonate dissolution played different roles as a function of specific aquifer mineralogy, releasing metals or influencing divalent cations response; (iv) conservative, mixing and oxidation processes were pointed out as possible mechanisms regulating variations of Cl⁻, SO₄²⁻ and NO₃⁻. Although studies suggested no parameter exceeded potable limits, most experiments were short-lived, possibly overlooking the CO₂ leakage response in a long-term exposure. Hence, further work is still needed specially to support relevant environmental legislation. © 2023 Society of Chemical Industry and John Wiley & Sons, Ltd.