Hydrogenation of CO₂ on Fe-Based Catalysts: Preferred Route to Renewable Liquid Fuels

Abstract

Catalytic hydrogenation of CO2 can be conducted either in one pot (CO2 hydrogenation) or in two stages (RWGS and CO hydrogenation). Its configuration consists of either three reactors in series with interim water removal (one-pot process) or CO2 separation and recycling (two-stage process) to reach high CO2 conversion. The two-stage process enables to reach optimal H2/CO and temperature in the hydrogenation reactor to yield higher productivity while minimizing production of the aqueous phase, which offset the advantages of the one-pot process. The techno-economic study determined that there is no apparent advantage in operating the hydrogenation reaction in one stage at current green hydrogen prices. The decision between the two routes should be based on catalyst stability and selectivity toward desired products. Blending 10% of liquid product from both processes with fossil fuels at current prices increases the fuel production cost by 30%, which can be offset by higher carbon pricing or equivalent incentives.

CO2 Hydrogenation to Gasoline and Aromatics: Mechanistic and Predictive Insights from DFT, DRIFTS and Machine Learning

“…However, studies targeting long-chain hydrocarbons, specifically C 5 + gasoline range hydrocarbon, and aromatics are relatively few. [9] Currently, gasoline-range hydrocarbons are produced from technologies such as petroleum refining, methanol-to-gasoline (MTG), and Fischer-Tropsch synthesis (FTS). These technologies rely on fossil fuels not only as feedstocks but also as energy sources.…”

“…Fairly speaking, a commendable level of progress has been made in CO 2 hydrogenation to short‐chain products such as methanol, [3–5] methane, [6] and C 2 −C 4 olefins [7,8] etc. However, studies targeting long‐chain hydrocarbons, specifically C 5+ gasoline range hydrocarbon, and aromatics are relatively few [9] . Currently, gasoline‐range hydrocarbons are produced from technologies such as petroleum refining, methanol‐to‐gasoline (MTG), and Fischer‐Tropsch synthesis (FTS).…”

The Effect of Mn, Al Doping on the CO2 Hydrogenation Performance of CaCO3‐Supported Fe‐Based Catalysts

“…[11,12] But photocatalysis, electrocatalysis, and photothermal catalysis are all characterized by low CO 2 conversion rates and are unsuitable for industrialization. In contrast, thermocatalytic CO 2 hydrogenation can achieve high CO 2 conversion and easily obtain long-chain hydrocarbons (Linear α-olefins, [13] Liquid Fuels, [14] etc.) with higher added value.…”

Techno-economic Analysis of Biogas Conversion to Liquid Hydrocarbon Fuels through Production of Lean-Hydrogen Syngas

“…Steam reforming, autothermal reforming, partial oxidation reforming, and dry reforming are used for syngas production. The choice of any of these processes depends on the feed composition and selected H 2 /CO ratio in the product. ,− Dry reforming reacts CH 4 and CO 2 , producing a low H 2 /CO ratio, beneficial for the production of liquid transportation fuels, − while saving the cost of CO 2 separation. However, catalyst deactivation caused by coke formation or sintering ,− ,, is still an issue, requiring the addition of steam at feed.…”