Polymer Science Faculty Research

Title

Carbon Dioxide Capture by Diamine-Grafted SBA-15: A Combined Fourier Transform Infrared and Mass Spectrometry Study

Document Type

Article

Publication Date

3-30-2005

Abstract

The adsorption and desorption of CO2 on diamine-grafted SBA-15 have been studied by infrared spectroscopy coupled with mass spectrometry. Diamine was grafted onto the SBA-15 surface by the reaction of [N-(2-aminoethyl)-3-aminopropyl]trimethoxysilane with the surface OH. CO2 is adsorbed on the diamine-grafted SBA-15 as bidentate carbonate and bidentate and monodentate bicarbonates at 25 °C. Bidentate carbonate and monodentate bicarbonates are the major surface species formed and decomposed during the concentration-swing adsorption/desorption process at 25 °C. Temperature-programmed desorption revealed that the monodentate and bidentate bicarbonates bound stronger to the diamine-grafted SBA-15 surface than the bidentate carbonate. The amount of CO2 desorbed from the carbonate and bicarbonate between 30 and 120 °C is 2 times more than that of CO2 adsorbed/desorbed during each cycle of the concentration-swing adsorption/desorption. Desorption at 120 °C removes the majority of the captured CO2 and regenerates the sorbent for CO2 capture at low temperature. Regeneration of the sorbent with temperature-swing adsorption gives a significantly higher CO2 capture capacity than concentration-swing adsorption. The use of a diamine-grafted sorbent, with an adsorption capacity of more than 1000 μmol/g of sorbent and a temperature-swing adsorption process, could be a cost-effective alternative to capture CO2 from power plant flue gases.

Publication Title

Industrial and Engineering Chemistry Research

Volume

44

Issue

10

First Page

3702

Last Page

3708

Link to Full Text

Share

COinS