Recovery

The Idea

The research is focused on CO₂ capture, with a focus on post-combustion capture. The capture of CO₂ from exhaust gas streams is one of the foremost prospects for reducing greenhouse gas emissions. The team is actively designing new porous solid materials at the sub-nanometer scale to trap CO₂ from power plants or mixed in with natural gas from unconventional gas reservoirs. These crystalline porous structures known as metal organic frameworks (MOFs) will be used to trap and release CO₂ in the presence of water vapor with low cost and high efficiency.

The main goal is to generate water stable MOFs that can sorb CO₂ in the presence of water vapor and nitrogen. After development of quality materials with exceptional properties, Shimizu hopes to carry the research beyond the bench top to an actual system; the ability of MOFs to interface at an actual power plant will be examined. Other goals include continuous development of other gas sorbents (in addition to CO₂) for many industrial applications. For example, sorbents can be developed for oxyfuel combustion (oxygen and nitrogen separation), natural gas purification, and biogas purification.

The Research

Current capture technology typically uses the formation of a chemical bond between an amine molecule and CO₂, in an aqueous solution. Regeneration of this sorbent requires heating both the amine and the solution to over 100°C. The ‘solid sponge’ developed by Shimizu’s team will directly capture CO₂ from the combusted gas stream; an aqueous solution will no longer be necessary to capture CO₂. Due to this modification, much less heat is necessary to release the CO₂ binding component, and this will result in large savings in energy and productivity at the regeneration step. At a power plant, this could save 50% in capture expense. Computer modeling will also be used to help design these MOFs, allowing the team to observe CO₂ capture at the molecular level. The MOFs which have the highest affinities for CO₂ - versus water and nitrogen gas- in a given pore will be selected.

The Results

Shimizu’s group has been very busy. The industrial partner ITT has advanced plans for the project and has applied to the Climate Change Emission Management Corporation (CCEMC) for pilot plant funding. There is also involvement in producing new nanoporous solids, and the structure, design and gas uptake is being revealed. In collaboration with their computational partners, a library of materials is being developed and understood. High throughput means of screening potential sorbents have been developed as well as access to a library of virtual MOF structures.

Research Grant

$563,000/3 years

Benefits to Canada and Beyond

This technology is applicable to both the oil and gas industry and beyond. Currently, Shimizu’s group is targeting post combustion CO₂capture materials; however, the research can easily transfer to broader problems. For example, other areas of potential gas separation application include, pre-combustion capture after coal gasification, O2 separation for oxyfuel combustion, and biogas purification.

Industry Applications

Physical adsorption mechanisms of a selective sorbent will be translated into dollar savings for CO₂ capture; a material which is capable of low pressure CO₂ sorption in the presence of water will be game changing. The technological impact of the work is enormous, because cheaper CO₂ capture will have a global market. A better understanding of MOF agents used for gas separations will be profound, and methods developed with this research could be extended to any targeted gas separation process.

Project Partners

Shimizu is partners with Inventys Thermal Technologies (ITT), and Enovex Technology. ITT provides proprietary knowledge on nanostructured solid sorbents and in-kind support. Enovex Technology is interested in oxyfuel combustion and potentially using Shimizu’s MOF technology to separate nitrogen from oxygen in this process. Enovex Technology has provided funding for this project.