Direct photoconversion of CO₂ from exhaust emissions into fuels and chemicals is one of the most ambitious challenges to a greater and more effective use of the solar source. Through an extensive and systematic evaluation of CO₂ photoreduction process, both in aqueous media and in gas-vapour stream for over 120 h, this work addresses the role of the photoreactor configuration on the CO₂ reduction efficiency, leading the study from laboratory to industrial environment, probably for the very first time. Therefore, the performance of a continuously stirred “semi-batch” (SB) photoreactor, a packed-bed (PB) photoreactor and a multi-tubular (MT) photoreactor has been compared in term of efficiency, products distribution and available energy. The results of the photocatalytic tests demonstrate a strong influence of process conditions on the photocatalyst performance and on the reaction path. The packed-bed (PB) configuration reports a maximum “apparent quantum efficiency” of about 6.0% and a net thermal energy of 0.3 kW h/m² generated in 120 h.

将CO ₂从废气排放直接光转化为燃料和化学物质是对更大更有效地利用太阳能的最雄心勃勃的挑战之一。通过对水性介质和气态蒸气中CO _2光还原过程进行超过120 h的广泛而系统的评估，这项工作解决了光反应器配置对CO ₂的作用。降低效率，这可能是第一次将研究从实验室引向工业环境。因此，已经在效率，产品分布和可用能量方面比较了连续搅拌的“半间歇”（SB）光反应器，填充床（PB）光反应器和多管（MT）光反应器的性能。光催化测试的结果证明了工艺条件对光催化剂性能和反应路径的强烈影响。填充床（PB）配置报告的最大“表观量子效率”约为6.0％，在120小时内产生的净热能为0.3 kW h / m ²。