Evaporative Emission Control for Hydrogen: Boil-off Mitigation with an Adsorbent-Based System

The transition toward renewable energy needs to be accelerated to address domestic energy security and climate change. Oil supplies in the United States are set to run out in less than fifty years, and the adverse outcomes of climate change will cost the United States $1.9 trillion annually by 2100 if not addressed. Renewable fuels, including hydrogen, have the potential to displace gasoline in the transportation sector. For hydrogen to be competitive with gasoline fuels, the current hydrogen storage and distribution system need improvements. Due to its high density, liquid hydrogen is gaining substantial interest for tackling this issue. Boil-off loss of liquid hydrogen during distribution and storage is one of the biggest challenges that must be addressed before liquid hydrogen can be adopted. The loss at a refueling station from a liquid hydrogen storage system can be up to 15% of the delivered fuel. It is expected to worsen for onboard liquid hydrogen storage, which is attractive for fuel-cell-powered heavy- duty transportation. Various strategies have been proposed to mitigate the boil-off loss for stationary storage, but they are not readily applicable to the vehicles or vessels that are continually moving. Under this proposed effort, NuMat Technologies (NuMat) proposes to develop an adsorbent-based system for recapturing boil-off hydrogen. A range of adsorbents will be evaluated, with a focus placed on metal-organic frameworks (MOFs). MOFs have excellent hydrogen adsorption capacity at low temperatures and pressure the relevant condition for boil-off capture. A successful development of this application will minimize boil-off losses, accelerating market adoption. NuMat is a leader in the commercialization of MOF-based technologies, having delivered some of the first commercial MOF solutions to the market. Furthermore, NuMat is developing technologies facilitating the adoption of hydrogen fuel cells, successfully producing results on two other SBIR projects guided by the DOE Hydrogen and Fuel Cell Technology Office. Under Phase I, NuMat will 1) evaluate a large set of adsorbents for their ability to capture hydrogen under relevant conditions, 2) establish the scale-up and forming procedure of the highest performing adsorbents, 3) design a prototype for the proposed capture and recovery process, and 4) Evaluate its economic benefits and identify commercialization partners. Once successful, this opportunity will allow NuMat to grow its business by playing a role in the transition towards the uprising hydrogen economy. To summarize, NuMat will develop an adsorbent-based system for recapturing boil-off gas from the liquid hydrogen storage to mitigate the loss to the atmosphere under this SBIR. This technology will increase the utilization efficiency and reduce the cost of transitioning to a hydrogen economy. The transition towards renewable energy will secure future energy for the United States and prevent the worst outcome of climate change.