Steam Methane Reforming (SMR) is the most common method for the production of commercial bulk hydrogen and proceeds according to equation 1.
- H2O + CH4 → CO + 3H2 (Eq 1)
The mixed gas product stream can be enriched in H2 by the Water Gas Shift (WGS) reaction which proceeds according to equation 2.
- CO + H2O → CO2 + H2 (Eq 2)
The equilibrium of equation 2 is temperature dependent, a high carbon monoxide conversion is observed at a low temperature but a practical reaction rate is observed at a high temperature. On an industrial scale, a two-step process is performed employing a high temperature and low temperature WGS sequence to take advantage of both the thermodynamics and kinetics of the reaction. In each step a different, temperature specific catalyst is used.
The shifted synthesis gas has a high H2 content, but also contains CO2, water and residual amounts of CH4 and CO. The high quality H2 product is achieved after processing through energy intensive and expensive methods for gas purification such as amine scrubber and Pressure Swing Adsorption (PSA) processes.
Overall, SMR is a complex process for the production of H2 that has a large equipment footprint to accommodate the numerous stages.
Scientists at Newcastle University have developed technology that supports the WGS process and eliminates the need for sequential high and low temperature reactions while producing pure H2 and CO2.
The approach uses a novel unmixed reaction technology incorporating SMR followed by an efficient, one step WGS process. Both processes are linked in series in one reactor unit.
This new technology is advantaged by:
- Significant reduction in the equipment footprint
- Significant reduction in capital expenditure for the construction of H2 production plants
- A new, single reactor that favours high conversion (greater than 90%) to H2 and CO2
- Increased reaction rates as a result of higher temperature operation than currently possible
- The process generates H2 and CO2 in separate product streams and therefore precludes the need for gas purification processes
- The process is scalable
This novel technology can be applied to established SMR technologies to reduce the cost and the equipment footprint of H2 production. It is also envisaged that it can be implemented as a stand-alone method for distributed H2 production in locations that possess the infrastructure for hydrocarbon delivery and storage or that need “on demand” H2 such as refuelling stations for hydrogen vehicles. The technology also provides an opportunity in developing economies where hydrogen production is required but domestic production capability is limited.
At present, research programs are directed at determining the lifetime of materials and the critical parameters of the process.
The University is seeking collaborative and/or license opportunities with a suitable industrial partner who can take the next steps of commercializing the technology.
A GB patent application has been filed for this technology.
Title: A new method for cheap and efficient hydrogen production
UK patent application no:151855.7
Filing Date: 7/07/15
Applicant: University of Newcastle upon Tyne
Dr Tim Blackburn, Science, Agriculture & Engineering Enterprise Team, Research and Enterprise Services, Devonshire Building, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK