(521cj) Solar-Driven Thermocatalytic Ethylene Oligomerization

Thermocatalytic routes have several advantages (e.g., high conversion rates, good selectivity, and scalability) and thus are widely used for commercial production of fuels and chemicals. However, today’s thermocatalytic technologies use fossil fuels as a source of energy and produce greenhouse gases that drive global climate change. Therefore, to become low- and zero-carbon emission technologies, these processes need to utilize renewable energy. One way to accomplish this goal is to convert solar energy into heat required to run chemical reactions. Ideally, such solar-thermal systems also need to operate under ambient sunlight (1-sun intensity) to make them suitable for large-scale use. We have therefore designed a solar-thermal flow-through reactor with a multi-layered selective solar absorber. We find that when exposed to natural sunlight, the selective absorber reaches a temperature of 120 °C sufficient to drive an industrially relevant ethylene oligomerization reaction where ethylene is electrochemically derived from CO₂ electrolysis. Moreover, we demonstrate that a supported nickel catalyst (Ni on SIRAL-30) converts ethylene into C4 hydrocarbons directly from the gas outlet stream of the CO₂ electrolysis cell. Overall, our work presents a framework to convert greenhouse gases into fuels using CO₂, water, and sunlight.