CO2 adsorption on zeolite 13X modified with hydrophobic octadecyltrimethoxysilane for indoor application. (20th February 2022)

• Record Type: Journal Article
• Authors: Kim, Minjae; Lee, Jae Won; Kim, Seonggon; Kang, Yong Tae
• Is Part Of: Journal of cleaner production. Volume 337(2022)
• Publication Date: 2022-02-20
• Subjects: CO2 adsorption -- CO2 selectivity -- Hydrophobic coating -- Indoor application -- Moisture resistance -- Zeolite; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2022.130597
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Hydrophobic-coated zeolite 13X (HZ) with octadecyltrimethoxysilane (ODTMS) exhibits a higher humidity resistance and CO2 -adsorption capacity than pristine zeolite 13X in indoor-simulating low–CO2 –concentration conditions. The hydrophobic coating modifies the surface characteristics and adsorption tendency of CO2 and H2 O, and these changes affect the gas selectivity for adsorption. Characteristic analysis (BET, TGA, and DVS) confirmed the rationality behind the use of zeolite@20 wt%ODTMS (HZ-2) for optimal loading of the hydrophobic coating under other experimental conditions. CO2 and moisture adsorption capacities of HZ-2 decreased by 15% (from 4.0 mmolCO2 /g to 3.4 mmolCO2 /g) to 44.1% (from 5.5 mmolH2 O/g to 3.3 mmolH2 O/g) under pure-gas conditions, respectively. The moisture resistance developed by the hydrophobic coating improves the CO2 selectivity in ambient-air conditions; this was tested in an indoor-condition-simulating chamber. The CO2 -capture performance of HZ-2 increased by 33.3% (from 0.3 mmolCO2 /g to 0.4 mmolCO2 /g) and the moisture-adsorption capacity decreased by 41.6% (from 3.3 mmolH2 O/g to 1.9 mmolH2 O/g). Furthermore, the CO2 gas selectivity of hydrophobic coated zeolite increased by 4.1 times. This modified synthesis provides a broader perspective on adsorbents for the utilization of CO2 -capture in indoor conditions. Graphical abstract: Hydrophobic functionalized adsorbent (HZ-2) is manufactured with microporous zeolite 13X and hydrophobic octadecyltrimethoxysilane (ODTMS) in simplified process. HZ-2 has high stability in regeneration temperature and cyclic adsorption/desorption process. Furthermore, adsorption capacity and selectivity of CO2 is enhanced in low concentration of CO2 indoor condition environment compared to the pristine material. Image 1