Tunable amine loading of amine grafted mesoporous silica grafted at room temperature: Applications for CO2 capture. (8th June 2022)

• Record Type: Journal Article
• Authors: Anyanwu, John-Timothy; Wang, Yiren; Yang, Ralph T.
• Is Part Of: Chemical engineering science. Volume 254(2022)
• Publication Date: 2022-06-08
• Subjects: CO2 capture -- Air capture -- Wet amine grafting -- Pore structures; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2022.117626
• Languages: English
• ISSNs: 0009-2509

Abstract

Highlights: Grafting at 30 °C as opposed to 85 °C resulted in higher amine loading. 30 °C grafted silica had higher CO2 capacity at 75 °C than 85 °C grafted silica. Grafting at 30 °C doesn't change the amine properties or configuration. Influence of grafting at 30 °C was demonstrated for different silicas & silanes. Abstract: SBA-15 was employed to study amine-grafting in dry and wet grafting conditions at low temperature. SBA-15 was amine-grafted at 30 °C and for contrast SBA-15 was conventionally grafted at 85 °C to determine how amine-grafting at 30 °C affects amine-grafting outcomes. It was found that under dry grafting conditions, adsorbents grafted at 30 and 85 °C exhibited similar amine loadings. It was also found that when water was added during grafting, adsorbents grafted at 30 °C displayed higher amine loadings than those at 85 °C. At 30 °C, more water can occupy the pore space of the SBA-15 prior to clogging of the pores, resulting in higher amine loading. This results in higher CO2 capacities at 75 °C for adsorbents grafted at 30 °C. The stability of materials grafted at 30 °C and the universality of the studied effects for other aminosilanes and mesoporous silica supports were demonstrated.