Nowadays, the increase of CO₂ concentration caused by the utilization of traditional fossil fuels has a negative impact on the environment and human health. Therefore, there is an urgent need to explore effective measures to control CO₂ emission. In this work, activated coal char for CO₂ capture was prepared with different carbonization temperatures by two-step method with KOH as the activator. The effects of carbonization temperature and adsorption temperature on the CO₂ adsorption performance of activated coal char were investigated. Elemental analysis, BET, XPS and SEM analysis of the activated coal char were performed. The results showed that the microporous structure has an important influence on the adsorption performance of activated coal char. With the increase of carbonization temperature, the microporous volume increases first following by a decrease and the amount of CO₂ adsorption also shares the same trend. For the adsorption temperature, as the adsorption temperature rises, the CO₂ adsorption capacity of activated coal char decreases. The maximum CO₂ adsorption capacity of 4.8 mmol/g was achieved at optimal conditions of carbonization temperature 600 °C, adsorption temperature 0 °C and pressure 1 bar. In addition, the activated coal char with a carbonization temperature of 600 °C also shows good selectivity for CO₂ over N₂, which indicated its prospects in the practical CO₂ capture applications.

如今，由于利用传统化石燃料而导致的CO ₂浓度增加，对环境和人类健康产生了负面影响。因此，迫切需要探索控制CO ₂排放的有效措施。在这项工作中，通过以KOH为活化剂的两步法，在不同的碳化温度下制备了用于捕获CO _2的活性炭。碳化温度和吸附温度对CO _2的影响研究了活性炭的吸附性能。进行了活性炭的元素分析，BET，XPS和SEM分析。结果表明，微孔结构对活性炭的吸附性能有重要影响。随着碳化温度的升高，微孔体积首先增加，然后减小，并且CO _2的吸附量也具有相同的趋势。对于吸附温度，随着吸附温度的升高，活性炭的CO ₂吸附能力降低。最大CO ₂在碳化温度600°C，吸附温度0°C和压力1 bar的最佳条件下，吸附容量达到4.8 mmol / g。此外，碳化温度为600°C的活性炭也对N ₂表现出对CO _2的良好选择性，这表明了其在实际CO ₂捕集应用中的前景。