高温CO_2吸附/吸收剂的研究进展

Recent Advances in the Research of High-temperature CO_2 Adsorbents and Absorbents

化石燃料火电厂是CO2主要排放源,直接脱除高温烟气中的CO2可以减少系统的能量损失,CO2高温吸附剂和吸收剂的开发研究得到重视。本文主要对高温CO2吸附剂中的碳基吸附剂、沸石、类水滑石化合物及高温CO2吸收剂中的锂基吸收剂和钙基吸收剂等进行分析比较:经过化学改性的类水滑石化合物在140℃以上具有高温吸附剂中最高的CO2吸附能力,钙基吸收剂中的PCC(沉淀碳酸钙)和CaO/Ca12Al14O33在600℃或更高温度下具有较高的吸收能力和循环反应活性。针对上述高温吸附/吸收剂目前存在的问题,提出以研究高温吸附/吸收机理,提高循环吸附/吸收CO2能力和改进其制备工艺作为今后研究的重点。

Fossil fuel-fired thermal power plants are a major source of CO2 emissions. The direct removal of the latter from high-temperature flue gases can contribute to a decrease in system energy losses. Hence, increasing attention has been directed to the research and development of high-temperature CO2 adsorbents and absorbents. Analyzed and compared were the carbon-based adsorbents, zeolites and hydrotalcite-like compounds in high-temperature CO2 adsorbents as well as lithium-based absorbents and calcium-based absorbents in high-temperature CO2 absorbents. Chemically modified hydrotalcite-like compounds at a temperature in excess of 140°C possess the highest CO2 adsorbing capacity among high-temperature adsorbents. At a temperature of 600°C or higher the precipitated calcium carbonate and CaO/Ca12A114O33 in calcium-based absorbents have a relatively high absorbing ability and cyclic reaction activity. In consideration of the existing problems regarding the above-mentioned high-temperature adsorbents and absorbents the authors have proposed as focuses of research the following items: high-temperature adsorption/absorption mechanism, the enhancement of the ability of cyclic adsorption/absorption of CO2 and the improvement of related preparation technology.