AGROINDUSTRIAL WASTE CONVERSION INTO ULTRAMICROPOROUS ACTIVATED CARBONS FOR GREENHOUSE GASES ADSORPTIONBASED PROCESSES

GOMEZ-DELGADO, EDWARD; NUNELL, GISEL; BONELLI P. R.; CUKIERMAN A. L.

Bioresource Technology Reports

Elsevier Ltd.

Lugar: Londres; Año: 2022

2589-014X

Feasibility of developing activated carbons (ACs) for greenhouse gases capture wasexplored via KOH activation of yerba mate twigs, a waste from industrial processing formanufacturing of a massively consumed to prepare a popular herbal tea?likebeverage. KOH impregnation and thermal treatment, conducted under flowing N2 atpre-established conditions. The effect of varying the impregnation KOH/precursor ratio(IR=1-3) and activation temperature (873-1073K) on yield, chemical and texturalmorphologicalfeatures of the resulting ACs, as well as on their adsorption capacity forCO2 were systematically examined. The impregnation ratio had the greatest influenceon the developed activated carbons. They showed BET surface areas between 1000and 2150 m2g-1, and completely microporous structures. The ACs derived fromcarbonization of the precursor in inert atmosphere and further activated with IR=2 at873K attained the highest capacity of CO2 adsorption at equilibrium (5.4mmolg-1).Forthis sample, dynamic assays for adsorption of CO2 and CH4 from single and binaryequimolar gaseous streams were also performed in a fixed-bed adsorber at 101.32kPaand 303K. Furthermore, regeneration experiments showed that the ACs almost keptthe initial dynamic adsorption capacity of both gases (1.4mmol CO2g-1 and 0.4 mmolCH4g-1) in five adsorption-desorption cycles., , , adsorption , .