Supported polyethyleneimine (PEI) adsorbent is one of the most promising commercial direct air capture (DAC) adsorbents with a long research history since 2002. Although great efforts have been input, there are still limited improvements for this material in its CO2 capacity and adsorption kinetics under ultradilute conditions. Supported PEI also suffers significantly reduced adsorption capacities when working at sub‐ambient temperatures. This study reports that mixing diethanolamine (DEA) into supported PEI can increase 46% and 176% of pseudoequilibrium CO2 capacities at DAC conditions compared to the supported PEI and DEA, respectively. The mixed DEA/PEI functionalized adsorbents maintain the adsorption capacity at sub‐ambient temperatures of −5 to 25 °C. In comparison, a 55% reduction of CO2 capacity is observed for supported PEI when the operating temperature decreases from 25 to −5 °C. In addition, the supported mixed DEA/PEI with a ratio of 1:1 also shows fast desorption kinetics at temperatures as low as 70 °C, resulting in maintaining high thermal and chemical stability over 50 DAC cycles with a high average CO2 working capacity of 1.29 mmol g−1. These findings suggest that the concept of “mixed amine”, widely studied in the solvent system, is also practical to supported amine for DAC applications.

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In this article, a modified tape casting method is employed by dispersing and ball milling of Al 2 O 3 powders in the poly (vinylidene fluoride) polymer, with the aim of developing uniform nanocomposite separators in the lithium-ion cell system. The surface morphology, pore structure, heat-resisting property, infrared property, and cell performance of the nanocomposite separators are investigated. The experimental results indicate that ball milling plays an important role in yielding homogeneous, porous nanocomposite separator membranes. The developed separator membranes exhibit high thermal stability and excellent electrochemical performance, therefore, are promising for use in the lithium-ion cell systems.

Summary Carbon capture and storage adopted by power plants has been extensively studied in recent years. However, little attention has been paid to carbon capture and storage for steel plants. After considering the differences between steel and power plants, a carbon capture system of reheating furnace flue gas is designed, based on the sensible heat of continuous casting slabs. As a result, a significant amount of waste heat resource from rolling mills can be effectively reused. By using Aspen Plus to optimize parameters of the capture system, such as regeneration pressure and reflux ratio, the regeneration energy consumption is obtained and the result is verified by comparing the data with that of other research. Under the constraint condition of 90% CO2 capture rate, simulation results show that the purity of CO2 obtained is 98.4%, and the annual CO2 capture capacity is about 70 000 tons. Finally, main parameters of continuous casting slabs and the heat recovery boiler are calculated. The heat load of the steam supplied for the reboiler is 8.5 MW, indicating that this steam generation method matches the carbon capture system.

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