Institute of Energy Technology, Laboratory of Energy Science and Engineering, ETH Zurich, Zurich, Switzerland.
ChemSusChem. 2012 Feb 13;5(2):411-8. doi: 10.1002/cssc.201100468. Epub 2012 Feb 1.
An option for reducing the release of greenhouse gases into the atmosphere is the implementation of CO(2) capture and storage (CCS) technologies. However, the costs associated with capturing CO(2) by using the currently available technology of amine scrubbing are very high. An emerging second-generation CO(2) capture technology is the use of calcium-based sorbents, which exploit the carbonation and calcination reactions of CaO, namely, CaO+CO(2) ↔CaCO(3). Naturally occurring Ca-based sorbents are inexpensive, but show a very rapid decay of CO(2) uptake capacity with cycle number. Here, we report the development of synthetic Ca-based CO(2) sorbents using a sol-gel technique. Using this technique, we are able to synthesize a nanostructured material that possesses a high surface area and pore volume and shows excellent CO(2) capture characteristics over many cycles. Furthermore, we are able to establish a clear relationship between the structure of the sorbent and its performance. After 30 cycles of calcination and carbonation, the best material possessed a CO(2) uptake capacity of 0.51 g of CO(2) per gram of sorbent; a value that is about 250 % higher than that for naturally occurring Havelock limestone.
减少温室气体排放到大气中的一种选择是实施二氧化碳捕获和储存（CCS）技术。然而，使用目前可用的胺洗涤技术捕获 CO2 的相关成本非常高。一种新兴的第二代 CO2 捕获技术是使用基于钙的吸附剂，利用 CaO 的碳化和煅烧反应，即 CaO+CO2↔CaCO3。天然存在的 Ca 基吸附剂价格低廉，但随着循环次数的增加，其 CO2 吸收能力会迅速下降。在这里，我们报告了使用溶胶-凝胶技术开发合成 Ca 基 CO2 吸附剂。使用该技术，我们能够合成一种具有高表面积和孔体积的纳米结构材料，并且在多次循环中表现出优异的 CO2 捕获特性。此外，我们能够在吸附剂的结构与其性能之间建立明确的关系。经过 30 次煅烧和碳化循环后，最好的材料每克吸附剂的 CO2 吸收能力为 0.51 克 CO2；这一数值比天然存在的海沃德石高出约 250%。
