Development of biomass based-activated carbon for adsorption dehumidification

• Published in: Energy reports Vol. 7; pp. 5871 - 5884
• Main Authors: Chairunnisa, Miksik, Frantisek, Miyazaki, Takahiko, Thu, Kyaw, Miyawaki, Jin, Nakabayashi, Koji, Wijayanta, Agung Tri, Rahmawati, Fitria
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-11-2021; Elsevier
• Subjects: Activated carbon; Adsorption dehumidification; Biomass; Carbon-based desiccant; Desiccant; Adsorption dehumidification; Biomass; Activated carbon; Carbon-based desiccant; Desiccant
• ISSN: 2352-4847; 2352-4847
• DOI: 10.1016/j.egyr.2021.09.003

Desiccant dehumidification systems can be utilized for decoupling moisture removal duty from the conventional mechanical vapor compression systems. Dehumidification using desiccant dehumidifiers is expected to exhibit a better energy efficiency. However, the high energy needed in the regeneration process limits its applicability. To realize the full potential of this technology, it is necessary to develop materials that can be regenerated using heat sources under 70 °C. In this study, activated carbons (ACs) derived from waste biomass were developed as desiccant materials. The ability of activated carbon (AC) to remove the moisture was controlled by carefully preparing the material to achieve the right operation window for optimum moisture sorption processes. The porous and surface characteristics of the newly-prepared AC were analyzed and compared with those of silica gel. The adsorption isotherm measurements were conducted, and the data were fitted with Henry–Sips and Do–Do isotherm models. The current ACs exhibit an excellent water adsorption capacity (up to 0.41 g/g). The efficacy of the ACs for dehumidification applications was assessed using the weather data from several regions of Indonesia, from North Sumatera to Papua. The results revealed that under the studied conditions, the new desiccant material showed a better dehumidification capacity than silica gel. Moreover, the reported AC can be regenerated using temperatures as low as 40 °C, which is readily available from waste heat, including the heat rejection from the condenser of an air-conditioning unit.
•Suitably activated carbons for moisture removal application were synthesized.•Air oxidation could enhance the surface properties and water adsorption capacity of activated carbon.•The dehumidification patterns between activated carbons and silica gel at the same working conditions are different.•Prepared activated carbons showed high dehumidification capacity under humid ambient air with regeneration temperature of at least 40 °C.