Realizing reversible capture and release of carbon dioxide at room temperature and pressure
2023-04-24
On the 24th, the reporter learned from the University of Science and Technology of China that Professor Liu Bo and Professor Xu Qiang from Southern University of Science and Technology have collaborated with an international research team to develop a promising carbon capture and storage method. For the first time, carbon dioxide was used as a guest molecule to simulate the structure of carbon dioxide hydrates, and cheap guanidine sulfate was used to co crystallize with carbon dioxide to form stable inclusion complexes, To achieve reversible capture and release of carbon dioxide under environmental temperature and pressure conditions. The research results were recently published in the journal Cell Reportable Matter Science. Carbon capture is an important link in carbon capture, utilization, and storage technology, which is of great significance for achieving the national "dual carbon" goals. Currently, carbon dioxide capture is mainly achieved through physical or chemical adsorption processes based on variable pressure and temperature. The physical adsorbent uses porous materials with high specific surface area, and carbon dioxide molecules enter the pores of the adsorbent through weak interactions. Although it has the advantages of low adsorption heat and easy regeneration, the flue gas and water vapor in the environment compete with carbon dioxide molecules for adsorption, greatly reducing the selectivity, capacity, and cycling performance of the adsorbent. Although chemical adsorbents such as ethanolamine and organic guanidine have high selectivity, the regeneration process of adsorbents requires significant energy consumption. How to reduce the energy consumption during carbon dioxide capture and release is of great significance. On the basis of previous work, researchers further applied dynamic hydrogen bonding framework structure transformation to carbon dioxide capture. Researchers have found that crystalline carbon dioxide inclusion complexes can be obtained from guanidine sulfate aqueous solution near room temperature. Further structural analysis indicates that carbon dioxide is encapsulated in a framework constructed through hydrogen bonding and electrostatic interactions between guanidine cations and sulfate ions. Surprisingly, carbon dioxide only has electrostatic interactions with the guanidine ions in the framework, which is also the driving force behind the formation of inclusion complexes and precipitation by co crystallization of carbon dioxide and guanidine sulfate. The moderate interaction enables both capture and release to occur under mild conditions. In addition, the co crystallization of carbon dioxide and guanidine sulfate per unit volume forms an inclusion complex, which contains 60 times the volume of carbon dioxide gas under the same temperature and pressure conditions, and the pressure of carbon dioxide reaches 6 MPa at the same temperature and volume, revealing its enormous potential in carbon capture storage and transportation. The researchers stated that the research team will actively promote the evaluation of energy consumption and cost of carbon capture on a pilot scale, in order to achieve the advantages of carbon capture in terms of energy consumption and economy. (Courtesy of China University of Science and Technology)
Edit: Responsible editor:
Source:
Special statement: if the pictures and texts reproduced or quoted on this site infringe your legitimate rights and interests, please contact this site, and this site will correct and delete them in time. For copyright issues and website cooperation, please contact through outlook new era email:lwxsd@liaowanghn.com