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Updated: Jun 12, 2026

A Synthetic Methodology for Preparing Impregnated and Grafted Amine-Based Silica Composites for Carbon Capture
Published on: September 29, 2023
A high surface area silica-supported aldehyde as a flow-compatible amine scavenger
A Michelle Reinhardt1,2, Jenny-Lee Panayides2, Darren L Riley1
1University of Pretoria South Africa darren.riley@up.ac.za.
Abstract:
A silica-supported aldehyde scavenger (SSA-3) was prepared from SBA-15 silica by sequential NaOH activation, alkylation with 1,2-dichloroethane, and Kornblum oxidation of the resulting alkyl chloride in DMSO/K2CO3. The material was characterised by FTIR, PXRD, TGA/DSC, SEM, and BET physisorption, confirming successful surface functionalisation and a dramatic increase in surface area upon imine formation with probe amines. Loading capacity was experimentally determined to be 0.43-1.31 mmol g-1, comparable to commercial polystyrene-aldehyde resins. A D-optimal design of experiments (22 runs) evaluated the effects of solvent type (mapped by PCA), flow rate (0.1-1.0 mL min-1), temperature (30-90 °C), and amine concentration (0.2-1.0 M) on scavenging efficiency. Only solvent type had a significant influence on performance: hydrophobic solvents afforded near-quantitative scavenging, while polar non-polarisable solvents (notably acetonitrile) reduced efficiency to approximately 75% due to a solvation screening mechanism. The scavenger is flow-compatible and demonstrates utility as an in-line purification tool for continuous flow synthesis of small-molecule libraries.
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