Related Experiment Video
Updated: Dec 13, 2025

Sulfate Separation by Selective Crystallization with a Bis-iminoguanidinium Ligand
Published on: September 8, 2016
Iminoguanidines: from anion recognition and separation to carbon capture
1Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. custelceanr@ornl.gov.
Abstract:
Iminoguanidines, first reported in 1898, have received renewed attention in the last 5 years due to their ability to recognize and separate anions from competitive aqueous environments. Iminoguanidines display high recognition abilities towards hydrophilic oxyanions (e.g., sulfate, chromate, carbonate) through strong and complementary hydrogen bonding from the guanidinium groups. This feature article reviews the fundamental anion recognition chemistry of iminoguanidines, as well as real-world applications including sulfate removal from seawater and CO2 capture for climate change mitigations.
More Related Videos
08:00Author Spotlight: Standardizing the Development of Amine-Based Silica Composites as CO2 Adsorbents for Direct Air Capture
Published on: September 29, 2023
09:04A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products
Published on: September 9, 2016
Related Concept Videos
Ion Exchange
Basicity of Heterocyclic Aromatic Amines
Aldehydes and Ketones with Amines: Imine and Enamine Formation Overview
Ion-Exchange Chromatography
Extraction: Advanced Methods
Aldehydes and Ketones with Amines: Imine Formation Mechanism
Imines are formed under mildly acidic conditions. A pH of 4.5 is ideal for the reaction.
If the pH is low or the solution is too acidic, the reaction slows down in the...