Preparation of Quaternized Bamboo Cellulose and Its Implication in Direct Air Capture of CO₂

Abstract

The substantial increase of the atmospheric CO2 concentration over the last few decades has steered toward research on direct air capture (DAC). DAC is one of the mobile-source carbon capture and storage (CCS) processes that is variant from the conventional point-source CCS in terms of easing the CO2 concentration levels and promoting negative carbon emission. We propose here a sustainable material based on the quaternization of bamboo fiber and the implication in DAC. The quaternized bamboo cellulose could adsorb CO2 at a medium relative humidity (RH) of 60–80%, with the efficiency of quaternary ammonium groups over 0.65. The CO2 capacity at higher RH strikingly decreased, which indicates the moisture-swing characteristics, and that was further validated by a desorption ratio of 0.70 under humid gas purge. The unique phenomenon that a dry atmosphere (e.g., RH < 20%) is not favored by adsorption was revealed and could be attributed to the hydrophobic feature of the sorbent inherited from natural lignocellulose. The results suggest that quaternized cellulose with a low cost may open up new possibilities for the utilization of moisture-swing CO2 adsorbents in damp circumstances.

Sorbents for the Direct Capture of CO2 from Ambient Air

“…The authors report the new sorbent has a faster CO 2 sorption rate than other reported sorbents . Since then, Armstrong et al., Song et al., and Hou et al . each reported their own newly developed sorbent to have a shorter half‐time—i.e.…”

Quaternary functionalized mesoporous adsorbents for ultra-high kinetics of CO2 capture from air

“…From thermodynamic point of view, the functional group efficiency under a certain CO 2 partial pressure is determined by the equilibrium constant, which reflects the binding ability of adsorbents with CO 2 . For moisture swing adsorbents, the CO 2 binding energy should be primarily affected by environmental humidity 24 and hydrophilicity of material 17 . Due to the hydrophilic feature of QA groups 27 , QMPR has higher water sorption capacity compared to MPR (Supplementary Table 1 ).…”

“…The grafting of QA cations with strong ionic bonding towards anions can avoid the overlap of functional groups inside mesopores 14 . Also, the mesopores can provide more surface area for functionalization, compared to macroporous supports 4 , 7 , 15 , 16 or cellulose fiber with limited pore structure 17 . This further provides sufficient channels for CO 2 diffusion and high efficiency ammonium sites for CO 2 to be captured.…”

Carbon Purchase Agreements, Dactories, and Supply-Chain Innovation: What Will It Take to Scale-Up Modular Direct Air Capture Technology to a Gigatonne Scale

“…Engineered approaches to CDR include direct air capture of CO 2 or DAC (Breyer et al, 2019;Hou et al, 2019), bioenergy with carbon capture and storage or BECCS (Fridahl and Lehtveer, 2018;Hanssen et al, 2020), and enhanced rock weathering (Strefler et al, 2018;Beerling et al, 2020), alongside more widely recognised nature-based solutions including reforestation, afforestation, soil carbon sequestration, and peatland restoration (Seddon et al, 2020). Regardless of individual perspective concerning the respective merits and limitations of engineered or nature-based carbon removal pathways (land-use, permanence, energy requirements, cost), a comprehensive suite of CDR solutions will be necessary to achieve carbon removal resembling anything close to a climate consequential scale; although the scope of this perspective is centred on scaling-up modular DAC technology.…”