Reactive Capture Of CO2 From Air Using Dual Functional Materials


Columbia University




Direct Air Capture (DAC) of CO2 is a potentially scalable negative CO2 emissions technology to meet the 2C rise in temperature to mitigate climate change. Beyond negative emissions, DAC technologies can be placed ubiquitously to utilize CO2 for wide variety of applications, ranging from CO2 utilization for value-added products, to enhanced oil recovery, to geological sequestration without expensive pipelines. Almost all the current DAC technologies are based on regeneration of sorbents/solvents using high-temperature steam to produce a CO2 stream for either utilization or sequestration. This utilization/sequestration step requires purification, compression and transport of CO2, manifesting into additional capex and opex and need for expensive infrastructure for CO2 transport. This problem can be overcome by regenerating the sorbent with a reducing gas (such as hydrogen) to directly produce a marketable product (e.g., renewable natural gas) which can use existing infrastructure.


Working with our university partner, Columbia university, Susteon is developing Dual Function Materials (DFMs) that combine the capture of CO2 from air and subsequent conversion of captured CO2 into a renewable natural gas (CH4). These DFMs are supported on novel monolithic structures to minimize pressure drop. Novel heating methods are being developed to minimize input energy for regeneration. Additional innovations include design of an efficient absorption-regeneration cycle and accompanying mechanical embodiments. Current lab-scale testing with leading sorbent candidates demonstrated fast kinetics of CO2 capture and sorbent regeneration to form CH4. Work is now focused on optimizing the reactor design, including dispersion of sorbent nanoparticle on high surface area supports, monolithic structure design, integrated rapid cycle temperature swing cycle, flow path architecture, and DFM bed construction.


This technology pathway enables high thermal efficiency for DAC CO2 followed by in-situ conversion to RNG. The combination of effective adsorption with fast temperature swing provides the benefits of lower cost materials and design, lower overall energy input, and higher efficiency, without the need of CO2purification, storage and transportation. This process can be designed in standard modules thus minimizing engineering and manufacturing costs. As the key input in this process is hydrogen needed for regeneration, plants can eb sited where a cheap source of waste hydrogen is available such as in petrochemical facilities.