In the medium to long term, fossil fuels and natural gas in particular will continue to play an important role in our energy mix. There is therefore a need for innovative solutions to mitigate their environmental impact. Adaptation measures like Carbon Capture and Sequestration (CCS) are insufficient, since the underground storage of carbon dioxide raises many technical and safety concerns. In a promising alternative, the energy potential of natural gas could be exploited without incurring CO2 emissions by extracting hydrogen from the thermal splitting of methane in a procedure known as ‘methane cracking’.
Project aim and results:
This programme investigates the CO2-free production of hydrogen from natural gas through the high-temperature dissociation of methane (CH4) into hydrogen (H) and solid black carbon (C). The feasibility of this ‘methane cracking’ technology has already been demonstrated in several experiments, and the IASS project is building on these results to develop an industrially viable process. We are examining key technological aspects including the use of catalysts (metallic or carbonaceous) in liquid metals, coke-removal systems, bubbling dynamics and reaction kinetics. A bubble column reactor with molten metal has been designed to facilitate the separation of the reaction products and enable continuous operation. In collaboration with the Karlsruhe Institute of Technology (KIT), we also built a prototype reactor. The first test run was completed in November 2013, and further tests were carried out in 2014 to confirm qualitative results for hydrogen conversion rates. Significant breakthroughs were made in the second half of 2014, when experiments proved that high-quality carbon (i.e., suitable for industrial use) could be efficiently produced at temperatures above 800oC. On that basis, we have identified a final set-up that relies on tin as the liquid metal of choice and on relatively inexpensive and easy-to-handle materials for the reactor.
- Prof. Alberto Abánades
- Dr. Horst Wenninger
- Dr. Renu Kumar Rathnam
- Dr. Kian Mehravaran
- Abánades, A., Rubbia, C., Salmieri, D. (2013): Thermal cracking of methane into Hydrogen for a CO2-free utilization of natural gas. - International Journal of Hydrogen Energy, 38, 20, p. 8491-8496.
- Abánades, A., Rubbia, C., Salmieri, D. (2012): Technological challenges for industrial development of hydrogen production based on methane cracking. - Energy, 46, 1, p. 359-363.