In order to create a sustainable, carbon-neutral society, it is of utmost importance to link the energy sector with the chemical industry. Radiation from nuclear power plants proves to be useful for H2 production from water or carriers such as methanol. In our study, we investigated the potential for the production of hydrogen and formaldehyde by endothermic radiolytic cracking of 50 mol% aqueous methanol, which can be produced by direct CO2 hydrogenation without distillation. We developed an elegant experimental setup and performed irradiation tests in the TRIGA reactor with system analysis by GC-MS (gas chromatography with mass spectroscopy), SEM-EDS (scanning electron microscopy with energy dispersive spectroscopy), XRD (X-ray powder diffraction) and Monte Carlo simulations of radiation absorption. Among the different routes tested, a semiconductor-based photocatalytic material (TiO2) increased the H2 yield by 24%. In the critical evaluation of radiation utilisation, spent fuel radiation sources were found to be promising as they require low heat exchange and could produce 3600 kg H2/day in a single spent fuel pool. The advantage of radiolytic methanol cracking lies in its ability to produce formaldehyde and hydrogen (∼53% methanol value increase), whereas conventional partial oxidation of methanol with O2 for formaldehyde production (only ∼31% methanol value increase) inevitably produces water, which reduces the overall energy efficiency.
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