I-Corps: Materials for CO2 Capture

I-Corps：二氧化碳捕获材料

• 批准号: 1556442
• 负责人: Reza Foudazi
• 金额: $ 5万
• 依托单位: New Mexico State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1556442&HistoricalAwards=false
• 关键词: Corps; Materials; CO2; Capture

CO2 appears as a contaminant or impurity in gas mixtures in oil industries, and because of the environmental impacts of CO2 emissions, lawmakers are beginning to require the separation of CO2 from combustion products. Consequently, CO2 separation is an issue in power plants, heavy industries, hydrogen production, natural gas sweetening, and air purification plants, among other industries. However, the currently available options for CO2 separation are limited and uneconomical. One contemporary method is absorption, a well-matured but energy-intensive and expensive approach. For example, the benchmark for chemical absorption based on monoethanolamine (MEA), a widely used absorbent, currently imposes costs of over $70 per metric ton of CO2 due to the high cost of solvent regeneration; overall, capturing CO2 emissions from power plants using conventional technologies requires 20-30% of the plant's energy output. This high cost is the single largest obstacle for the widespread industrial adoption of CO2 capture technologies. Therefore, industry has an urgent need for the development of high-performance and low-cost technologies and materials that enable capital-efficient CO2 capture. A promising alternative process for CO2 capture is adsorption by porous materials: candidate adsorbents for CO2 separation should selectively adsorb CO2 from gas mixtures and have large surface areas to accommodate CO2 molecules into the pores. Based on a novel, suitable adsorbent recently developed by members of the proposed I-Corps team, the aim of this project is to commercialize a new series of adsorbents (zeolitic imidazolate frameworks, or ZIFs) that exhibit superior selectivity for separating CO2 from other gases and that have significant surface area to store it. This technology has been developed at a critical time for the CO2 capture market. Strict emission standards have been imposed by the U.S. government and several other countries and entities such as Canada, China, and the European Union, but there is not yet an optimal or even existing product available to meet the required needs. The proposed ZIF, with its outstanding capability for high-selectivity CO2 capture, therefore provides a revolutionary solution at a time of severe market need. Metal-organic frameworks (MOFs) are hybrid porous materials constructed from organic linkers and metal-containing nodes. The typical specific surface areas - and hence, gas adsorption capacities - that MOFs provide are an order of magnitude higher than those of zeolites. ZIFs are a subfamily of MOFs. They have an M(Im)4 zeolite-type framework in which tetrahedral elements, M, are transition metals bridged by imidazolate (Im) moieties. ZIFs can adsorb CO2 emissions and store five times more than existing adsorbents before requiring regeneration. For example, each unit volume of ZIF-69 can store up to 83 times its volume in CO2. Moreover, ZIFs can exhibit high chemical and thermal stability, and therefore can be robust processes for CO2 capture. In this comprehensive study, we propose the synthesis of a new subclass of ZIFs that, as indicated by Monte-Carlo-based simulation, have a 100-fold-increased CO2 capture capacity compared to the isostructural ZIFs. This increase in CO2 capture capacity was accompanied by only negligible changes in capture capacity for CH4, H2, and N2; therefore, the uptake ratio of CO2 to the other gases increased significantly, indicating very high selectivity for CO2 separation in our novel ZIFs. This set of abilities could significantly reduce the cost of carbon separation and capture at combustion-based power plants, heavy industries, natural gas processing, and hydrogen production companies.

在石油工业的混合气体中，二氧化碳是一种污染物或杂质，由于二氧化碳排放对环境的影响，立法者开始要求将二氧化碳从燃烧产物中分离出来。因此，二氧化碳分离在发电厂、重工业、制氢、天然气脱硫和空气净化厂等行业都是一个问题。然而，目前可供选择的二氧化碳分离是有限的和不经济的。一种现代的方法是吸收，这是一种成熟但能源密集且昂贵的方法。例如，以广泛使用的吸收剂单乙醇胺为基础的化学吸收基准，由于溶剂再生成本高，目前每公吨二氧化碳的成本超过70美元；总的来说，使用传统技术捕获发电厂排放的二氧化碳需要发电厂20-30%的能源输出。这种高成本是二氧化碳捕获技术在工业上广泛应用的最大障碍。因此，工业迫切需要开发高性能和低成本的技术和材料，以实现资本高效的二氧化碳捕获。一种很有前途的CO2捕获替代方法是多孔材料的吸附：用于CO2分离的候选吸附剂应该有选择地从气体混合物中吸附CO2，并且具有较大的表面积以容纳CO2分子进入孔隙。基于I-Corps团队成员最近开发的一种新颖、合适的吸附剂，该项目的目标是将一系列新的吸附剂（沸石咪唑盐框架或ZIFs）商业化，这些吸附剂在将二氧化碳与其他气体分离方面表现出卓越的选择性，并且具有很大的表面积来储存二氧化碳。这项技术是在二氧化碳捕集市场的关键时期开发的。美国政府以及加拿大、中国和欧盟等其他几个国家和实体已经实施了严格的排放标准，但目前还没有一种最佳的甚至现有的产品可以满足所需的需求。ZIF具有出色的高选择性CO2捕获能力，因此在严峻的市场需求时期提供了革命性的解决方案。金属-有机骨架（MOFs）是由有机连接体和含金属节点构成的杂化多孔材料。mof提供的典型比表面积——因此，气体吸附能力——比沸石高出一个数量级。zif是mof的一个亚族。它们具有M(Im)4沸石型框架，其中四面体元素M是由咪唑酸酯（Im）基团桥接的过渡金属。在需要再生之前，zif可以吸附二氧化碳排放，并比现有吸附剂多储存五倍。例如，每单位体积的ZIF-69可以储存高达其体积83倍的二氧化碳。此外，zif具有很高的化学稳定性和热稳定性，因此可以作为强有力的CO2捕获过程。在这项综合研究中，我们提出了一种新的ZIFs亚类的合成，正如蒙特卡罗模拟所表明的那样，与同结构ZIFs相比，它的二氧化碳捕获能力增加了100倍。二氧化碳捕获能力的增加伴随着CH4、H2和N2捕获能力的变化可以忽略不计；因此，CO2对其他气体的吸收比显著增加，表明我们的新型zif对CO2的分离具有很高的选择性。这一套能力可以显著降低燃烧发电厂、重工业、天然气加工和氢气生产公司的碳分离和捕获成本。