Capturing CO2 with (or without) CDs

today’s cyclodextrin: Capturing CO2 with (or without) CDs

Researchers at the University of California, Berkeley, have developed a material named COF-999, a fluffy yellow powder capable of capturing carbon dioxide (CO₂) from the atmosphere with remarkable efficiency. Just under half a pound (approximately 200 grams) of COF-999 can absorb about 44 pounds (20 kilograms) of CO₂ annually, matching the carbon sequestration capacity of a mature tree over the same period.

COF-999 is a covalent organic framework (COF) characterized by its porous structure, which provides a large surface area for gas adsorption. The internal surfaces of this material are lined with amines—compounds that effectively bind to CO₂ molecules. When air passes through COF-999, the amines capture CO₂, and the gas can later be released by heating the material to about 140°F (60°C), allowing for repeated use. Notably, COF-999 has demonstrated stability over at least 100 adsorption-desorption cycles without degradation.

This innovation holds significant promise for direct air capture (DAC) technologies, which aim to reduce atmospheric CO₂ levels to mitigate climate change. The efficiency and durability of COF-999 could enhance the viability of DAC systems, potentially accelerating efforts to lower greenhouse gas concentrations in the atmosphere.

But did you know that cyclodextrins can be used for carbon-dioxide capturing too?
Cyclodextrins (CDs), cyclic oligosaccharides, are studied as potential CO2 capture agents due to their unique molecular structures and high selectivity towards CO2 – a paper from Mikael Bols

CO2 complexation with cyclodextrins – PMC

CO2 complexation with cyclodextrins

Today’s cyclodextrin:
CO2 complexation with cyclodextrins by Mikael Bols‘ group:
Carbon dioxide emissions from industrial processes, power generation, and transportation contribute significantly to global warming and climate change. Carbon capture and storage (CCS) technologies are essential to reduce these emissions and mitigate the effects of climate change. Cyclodextrins (CDs), cyclic oligosaccharides, are studied as potential CO2 capture agents due to their unique molecular structures and high selectivity towards CO2. In this paper the binding efficiency of a number of cyclodextrins towards CO2 is investigated. It is found that the crystal structure of α-cyclodextrin with CO2 has a 1:1 stoichioimetry and that a number of simple and modified cyclodextrins bind CO2 in water with a Kg of 0.18–1.2 bar−1 (7–35 M−1) with per-O-methyl α-cyclodextrin having the highest CO2 affinity.

BJOC – CO2 complexation with cyclodextrins (beilstein-journals.org)