Photocatalytic dry reforming: what is it good for?†
A techno-economic model of a solar dry reforming process is used to simulate fifteen case studies in which the reaction is used to produce hydrogen, methanol, and butanal from feedstocks obtained from petrochemical, biogas, landfill gas, flue gas, and direct air capture sources. The goal of this analysis is to provide perspective into the remaining technical challenges associated with the commercial application of a solar-driven dry reforming process, which has great potential to be a building block in the burgeoning global circular economy, as a result of the fact that it consumes two greenhouse gases: carbon dioxide and methane. The average available real-world scale of each feedstock is then used to postulate a minimum catalyst activity that would make the use of these feedstocks competitive with their existing petrochemical alternative. It is found that the majority of the minimum catalyst activities required by each of these applications has been demonstrated in the scientific literature in the past two decades. However, in order for these intrinsic catalytic rates to be practically realisable, significant improvements in photoreactor engineering are required to minimize transport losses and maximize photocatalyst-photon contact.