Transforming Atmospheric CO2 into Chemical Feedstocks: A Comparative Route Assessment
摘要
This study investigates the techno-economic prospects of converting direct-air-captured CO2 into valuable chemicals to reduce capture costs and encourage wider use. Overall, twenty-three bulk chemicals are evaluated based on safety, reaction severity, catalyst recovery, fossil reliance, market demand, CO2 uptake, energy use, and 100 kt/y economics. Hazardous, endothermic, and homogenous catalyst routes are excluded, leaving five reasonable options, synthesized either via electrochemical or thermocatalytic route. For the former type of synthesis, oxalic acid turns out to be the most optimal while all the proposed solutions are found to be currently unprofitable for the thermocatalytic routes given green hydrogen cost. Nevertheless, dimethyl ether (DME) becomes financially attractive option for the scenario that is expected to take place by 2030 based on expected advancements in green hydrogen technology. Thus, DME is deemed to be the favored short-term method, barring hydrogen cost decreases, but oxalic acid is better suited for long-term development when its scale-up to industrial phase becomes feasible. The findings of this research will facilitate transformation of CO2, once recognized as a waste, into a valuable raw material encouraging CO2 capture despite the economic burden of direct air capture (DAC) technology. As a result, not only can the dire effects of global warming be mitigated, but a novel feedstock can also be introduced to the industry as an alternative to fossil fuels.