Biogas improving by adsorption of CO2 on modified waste tea activated carbon

Management of surgical mask waste to activated carbons for CO2 capture

“…For example, activated carbon as a CO 2 sorbent was obtained from waste tea [35] where the adsorption of CO 2 at 30 °C and 1 bar was 2.5 mmol/g, from waste polymers resulting in carbonization of carbon on which CO 2 adsorption at 25 °C and 1 bar was up to 3.0 mmol/g [36] , or from coconut shells that showed CO 2 uptake at 1 bar up to 3.7 mmol/g at 25 °C and up to 5.12 mmol/g at 0 °C. Also, coals from biomass such as bamboo, starch or sawdust were used as carbon precursors for CO 2 adsorption, showing a CO 2 capacity of approx.…”

Insights into the Critical Role of Abundant-Porosity Supports in Polyethylenimine Functionalization as Efficient and Stable CO2 Adsorbents

“…38 The AC and another polymeric resin (XAD4) had more obvious microporous structures with smaller average pore sizes, as reflected by the sharp N 2 adsorption at low relative pressures, and the exhibited type IV N 2 isotherms with clear hysteresis loops at higher relative pressures also indicated the existence of mesopores. 39 In addition, the corresponding textural parameters also displayed significant differences, for example, AC and XAD4 had greater specific surface areas and micropore volumes but smaller average pore sizes, and SiO 2 and HP20 possessed more prominent pore volumes and sizes. After PEI impregnation, the porosities of the functionalized adsorbents were apparently declined because of PEI molecules filling the pores, embodied in the significantly reduced specific surface areas and pore volumes.…”

A review of CO2adsorbents performance for different carbon capture technology processes conditions

“…Minimal literature studies the preparation of the conventional adsorbent such as zeolite, silica material, and activated carbon from waste materials (i.e., fly ash, rice husk ash, oil sands coke, and waste tea) and modified by amine (PEI, 3-aminopropyltriethoxysilane (APTES), DEA, methyl diethanolamine (MDEA), and TEPA) or metal (rare earth metal: lanthanum (La) and cerium (Ce)). [330][331][332][333][334][335] Among these modified adsorbents, La-functionalized LiX zeolite exhibited the highest CO 2 adsorption capacity of 4.36 mmol g −1 at 0 °C and 1 bar, followed by 62 wt.% PEI-modified rice husk ash derived MCM-41 (3.02 mmol g -1 at 75 °C), 57 wt.% PEI-modified pulverized coal fly ash derived MCM-41 (2.97 mmol g -1 at 75°C), and EDA-modified waste tea derived activated carbon (MWTAC) (2.48 mmol g −1 ). 332,333,335 Low CO 2 adsorption capacity is presented by PEI (molecular weight: 600 and 1200 g mol −1 )-impregnated fly ash derived activated carbons, APTES-modified rice husk derived silica material (ASiO 2 ), and activated carbons impregnated with 1.15, 0.49, and 1.03 mmol N g −1 AC of DEA, MDEA, and TEPA ranging between 0.16 and 0.90 mmol g −1 after the modification.…”

“…[330][331][332][333][334][335] Among these modified adsorbents, La-functionalized LiX zeolite exhibited the highest CO 2 adsorption capacity of 4.36 mmol g −1 at 0 °C and 1 bar, followed by 62 wt.% PEI-modified rice husk ash derived MCM-41 (3.02 mmol g -1 at 75 °C), 57 wt.% PEI-modified pulverized coal fly ash derived MCM-41 (2.97 mmol g -1 at 75°C), and EDA-modified waste tea derived activated carbon (MWTAC) (2.48 mmol g −1 ). 332,333,335 Low CO 2 adsorption capacity is presented by PEI (molecular weight: 600 and 1200 g mol −1 )-impregnated fly ash derived activated carbons, APTES-modified rice husk derived silica material (ASiO 2 ), and activated carbons impregnated with 1.15, 0.49, and 1.03 mmol N g −1 AC of DEA, MDEA, and TEPA ranging between 0.16 and 0.90 mmol g −1 after the modification. 330,331,334…”