Catalytic methanol cracking to hydrogen and formaldehyde over heterogeneous catalysts by radiolysis: Sectoral industrial symbiosis by waste radiation utilisation

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 H 2 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 CO 2 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 (TiO 2 ) increased the H 2 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 H 2 /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 O 2 for formaldehyde production (only ∼31% methanol value increase) inevitably produces water, which reduces the overall energy efficiency. • A reliable experimental setup for methanol radiolysis was developed. • The photocatalytic route increases the yield of H 2 and HCHO. • Catalyst characterization and particle Monte Carlo simulations were carried out. • Waste radiation was identified as a suitable energy source. • By utilizing a typical spent fuel pool, 3600 kg H 2 /day can be produced.