Hydrate membranes offer new approach to purify natural gas

 A pair of Colorado School of Mines professors has been awarded $300,000 by the National Science Foundation to design a new kind of membrane that uses gas hydrates to purify natural gas.
Moises Carreon, associate professor of chemical and biological engineering, and Carolyn Koh, William K. Coors Distinguished Professor in Chemical and Biological Engineering, are the investigators on the project, titled “Removal of Non‐Hydrocarbon Natural Gas Impurities over Gas Hydrate Membranes.”
“We are proposing a unique and distinctive approach to remove impurities from natural gas,” Carreon said. “Specifically, we propose a separation process in which gas hydrate membranes will be employed to capture natural gas impurities, such as carbon dioxide, nitrogen and mercaptans.”
Natural gas processing is the largest industrial gas separation technology in the world, with close to 100 trillion standard cubic feet of natural gas used every year. Natural gas consists primarily of methane, carbon dioxide, nitrogen, hydrogen sulfide and higher alkanes, and it’s highly desirable to remove from the methane the remaining compounds to improve its heat content.
Membrane technology has been demonstrated to be a viable energy-saving method to remove most of these impurities, requiring less energy than current benchmark technologies for removing carbon dioxide and nitrogen. Carreon and Koh hope that gas hydrate membranes will also result in a viable energy-saving method to potentially reduce the costs associated with natural gas purification.
“Fundamentally, it is expected that the proposed separation will be promoted by a dynamic replacement in which there will be selective incorporation of natural gas impurity molecules from the feed gas to the guest molecules in the formed hydrate crystalline lattice,” Koh said. “This work will lead to seminal scientific knowledge of membrane science coupled to gas hydrates.”

Emilie Rusch, Public Information Specialist, Communications and Marketing | 303-273-3361 | erusch@mines.edu
Mark Ramirez, Managing Editor, Communications and Marketing | 303-273-3088 | ramirez@mines.edu