Rapid synthesis of solid amine composites based on short mesochannel SBA-15 for CO2 capture. (15th March 2020)

• Record Type: Journal Article
• Authors: Ma, Beibei; Lin, Rijia; He, Hui; Wu, Qinghua; Chen, Shuixia
• Is Part Of: Composites. Number 185(2020)
• Publication Date: 2020-03-15
• Subjects: Short mesochannel SBA-15 -- Non-hydrothermal -- NH3·H2O catalysis -- CO2 adsorption -- Adsorption kinetics; Composite materials -- Periodicals; Materials science -- Periodicals; Composite materials; Periodicals; Electronic journals; 620.118
• DOI: 10.1016/j.compositesb.2020.107782
• Languages: English
• ISSNs: 1359-8368

Abstract

Abstract: Hydrothermal is common process for synthesizing well-ordered mesoporous silica, however, it costs time and energy simultaneously. To improve the efficiency of synthesis process, it is necessary to propose a facile synthesis strategy with less time and energy requirement. In this study, an innovative non-hydrothermal method using NH3 ∙H2 O as catalyst after ripening step is developed to prepare SBA-15 with short mesochannels (SSBA-15) for the first time. The synthesis period of SSBA-15 framework was extremely shortened within 40 min under the optimized conditions (30 min of ripening step and 25% of NH3 ∙H2 O concentration), while obtained material exhibits well-ordered hexagonal pore structure and fine particle morphology of SSBA-15 (pore length of 250 ± 50 nm and mesopore size of 9.8 nm). This method can also be employed to synthesize conventional SBA-15 successfully. Moreover, the application of SSBA-15 as support of solid amine adsorbents on CO2 adsorption and well-fitting of experimental CO2 adsorption data with Avrami and intraparticle diffusion models reveal that the adsorbents combine the advantages of micro-mesoporous structure, short mesochannel and amine reagents (high affinity of CO2 ), resulting in enhanced molecular diffusion, fast adsorption kinetics and high CO2 adsorption capacity. Notably, the solid amine adsorbents exhibited excellent regeneration ability during ten adsorption-desorption cycles. This work opens up new opportunities in efficient preparation of materials that require hydrothermal process. Graphical abstract: Image 1 Highlights: A non-hydrothermal strategy is developed to extremely shorten the synthesis period of SSBA-15. Effects of ripening time and NH3 ·H2 O concentration on the structure of the short-pore SBA-15 are expounded. SSBA-15-PEI(600) showed excellent regenerative stability during ten cycles. The micro-mesoporous structure facilitated dispersion of amine reagents and diffusion of CO2 .