Our technology involves an onboard post combustion combined reactor which captures CO₂ directly from the exhaust gas and utilizes it as a feedstock to synthesize value-added products. At the core of this technology is a ceramic membrane which captures CO₂ to release it in the permeate side for further catalytic hydrogenation to produce the value-added chemical commodity (Figure 1).

Combined reactor for CO₂ capture and liquid fuel production

There are three main technologies for carbon capture namely post-combustion, pre-combustion, and oxy-fuel combustion capture. We mainly focus on post-combustion carbon capture technology given that it allows retrofitting on existing system without much alteration requirements. There are several types of post combustion technologies including absorption solvent-, adsorption sorbent-, and membrane -based separation.

Comparison:

Unlike solvent- and sorbent-based capture techniques, membrane-based processes present fundamental advantages in cost and energy consumption due to their capability of delivering high-pressure CO₂ and not using energy-intensive steam or chemical loads. However, the major issue arises due to the tradeoff between selectivity and permeability (Robeson upper bound rule).

Our multiphase solids/molten carbonate (MC) composites are emerging class of membrane which operates on high-temperature without the limitation of Robeson rule. The operating temperature of these membranes also matches well with that of the exhaust gas at the exit, thus allowing the heat in the exhaust gas to be directly utilized for membrane operation. The membrane reactor can be practically inserted along the exhaust system to directly capture hot CO₂ thus enabling retrofit and cost saving design.