Malhotra Deepika, Koech Phillip K, Heldebrant David J, Cantu David C, Zheng Feng, Glezakou Vassiliki-Alexandra, Rousseau Roger
Energy Processes and Materials Division, Pacific Northwest National Laboratory, Richland, WA, 99352, USA.
Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA, 99352, USA.
ChemSusChem. 2017 Feb 8;10(3):636-642. doi: 10.1002/cssc.201601622. Epub 2017 Jan 11.
Anthropogenic CO emissions from point sources (e.g., coal fired-power plants) account for the majority of the greenhouse gases in the atmosphere. Water-lean solvent systems such as CO -binding organic liquids (CO BOLs) are being developed to reduce the energy requirement for CO capture. Many water-lean solvents such as CO BOLs are currently limited by the high viscosities of concentrated electrolyte solvents, thus many of these solvents have yet to move toward commercialization. Conventional standard trial-and-error approaches for viscosity reduction, while effective, are time consuming and economically expensive. We rethink the metrics and design principles of low-viscosity CO -capture solvents using a combined synthesis and computational modeling approach. We critically study the effects of viscosity reducing factors such as orientation of hydrogen bonding, introduction of higher degrees of freedom, and cation or anion charge solvation, and assess whether or how each factor affects viscosity of CO BOL CO capture solvents. Ultimately, we found that hydrogen bond orientation and strength is the predominant factor influencing the viscosity in CO BOL solvents. With this knowledge, a new CO BOL variant, 1-MEIPADM-2-BOL, was synthesized and tested, resulting in a solvent that is approximately 60 % less viscous at 25 mol % CO loading than our base compound 1-IPADM-2-BOL. The insights gained from the current study redefine the fundamental concepts and understanding of what influences viscosity in concentrated organic CO -capture solvents.
来自点源（如燃煤发电厂）的人为一氧化碳排放占大气中温室气体的大部分。正在开发贫水溶剂体系，如一氧化碳结合有机液体（CO BOLs），以降低捕获一氧化碳的能量需求。许多贫水溶剂，如CO BOLs，目前受到浓电解质溶剂高粘度的限制，因此这些溶剂中的许多尚未实现商业化。传统的降低粘度的标准试错方法虽然有效，但耗时且经济成本高。我们使用合成与计算建模相结合的方法重新思考低粘度一氧化碳捕获溶剂的指标和设计原则。我们批判性地研究了降低粘度因素的影响，如氢键的取向、引入更高的自由度以及阳离子或阴离子电荷溶剂化，并评估每个因素是否以及如何影响CO BOL一氧化碳捕获溶剂的粘度。最终，我们发现氢键的取向和强度是影响CO BOL溶剂粘度的主要因素。基于这一认识，合成并测试了一种新的CO BOL变体1-MEIPADM-2-BOL，得到了一种在25摩尔%一氧化碳负载量下粘度比我们的基础化合物1-IPADM-2-BOL低约60%的溶剂。当前研究获得的见解重新定义了关于影响浓有机一氧化碳捕获溶剂粘度的基本概念和理解。
