Emerging trends in direct air capture of CO₂: a review of technology options targeting net-zero emissions

Abstract

The increasing concentration of carbon dioxide (CO2) in the atmosphere has compelled researchers and policymakers to seek urgent solutions to address the current global climate change challenges.

Photocatalytic conversion of carbon dioxide, methane, and air for green fuels synthesis

“…(DAC), which uses specialized chemical processes to capture CO 2 directly from ambient air. 31,32 Another example is carbon mineralization, which involves converting CO 2 into stable mineral forms through chemical reactions with naturally occurring minerals. 33 There are also efforts to develop novel catalysts and electrochemical methods for converting CO 2 into valuable products, such as fuels, chemicals, and building materials.…”

“…30 One example of CO 2 capture and conversion technology is direct air capture (DAC), which uses specialized chemical processes to capture CO 2 directly from ambient air. 31,32 Another example is carbon mineralization, which involves converting CO 2 into stable mineral forms through chemical reactions with naturally occurring minerals. 33…”

Reduced Order Machine Learning Models for Accurate Prediction of CO2 Capture in Physical Solvents

“…2 The existing CO 2 capture techniques include, absorption, 3 adsorption, 4 membrane separation, 5 cryogenic separation, 6 mineral carbonation, 7 bioenergy with carbon capture and storage (BECCS), 8 and direct air capture (DAC). 9 Among all these methods, solvent-based absorption is the most widely used, due to its high efficiency and low cost of operation. 10 Particularly, physical absorption is an attractive option for precombustion CO 2 capture from concentrated streams at high pressures due to the noncorrosive nature, lower regeneration energy, and high availability of physical solvents.…”

“…The technological pathways pursued for CO 2 capture include precombustion (CO 2 concentration of 15–60% and partial pressure of 2–7 MPa), postcombustion (CO 2 concentration of 3–20% and partial pressure of 0.003–0.02 MPa), oxy-fuel combustion routes (CO 2 concentration > 95% and partial pressure of 0.1–0.5 MPa), and direct air carbon capture (CO 2 concentration of ∼400 ppm and pressure < 0.1 MPa) . The existing CO 2 capture techniques include, absorption, adsorption, membrane separation, cryogenic separation, mineral carbonation, bioenergy with carbon capture and storage (BECCS), and direct air capture (DAC) . Among all these methods, solvent-based absorption is the most widely used, due to its high efficiency and low cost of operation .…”

CO2 Capture by Diamines in Dry and Humid Conditions: A Theoretical Approach

“…With the exception of KS-1, a proprietary sterically hindered amine, using amine solutions for carbon capture was found to be cost-prohibitive, mostly because of the high-energy requirements for amine regeneration, in addition to other drawbacks, such as amine decomposition into harmful chemicals, amine evaporation, oxidative degradation, and equipment corrosion . Hence, new technologies are being developed at an increasingly faster pace. − Among the most promising technologies is the adsorption of CO 2 over amine- and polyamine-supported porous materials. Over the past decade or so, the number of new and established companies with commercial or near commercial carbon capture processes from large point sources or directly from air, by supported amine materials, has grown significantly.…”