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Updated: Jun 8, 2025
07:50
Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
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Chemically robust functionalized covalent organic framework for the highly efficient and selective separation of
Sahel Fajal1, Dipayan Ghosh1, Kishalay Biswas1
1Department of Chemistry, Indian Institute of Science Education and Research (IISER) Pune, Dr Homi Bhaba Road, Pashan, Pune 411008, India. sghosh@iiserpune.ac.in.
Materials Horizons
|November 1, 2024
Summary
Researchers developed advanced covalent-organic frameworks (COFs) for efficient bromine sequestration. These functionalized COFs demonstrate high capacity, fast kinetics, and reusability for both vapor and aqueous phases, addressing limitations of current adsorbents.
Area of Science:
- Materials Science
- Environmental Chemistry
- Chemical Engineering
Background:
- Effective bromine sequestration is crucial for chemical industry safety and environmental protection.
- Existing adsorbents suffer from limited capacity, low retention, and slow kinetics, hindering practical applications.
- Developing novel materials with enhanced host-guest interactions is essential for efficient bromine capture.
Purpose of the Study:
- To design and synthesize functionalized covalent-organic frameworks (COFs) for superior bromine sequestration.
- To systematically investigate the impact of binding sites on host-guest interactions and adsorption performance.
- To evaluate the capacity, kinetics, selectivity, and reusability of the developed COFs for bromine capture.
Main Methods:
- Synthesis of functionalized covalent-organic frameworks (COFs) with tailored binding sites.
- Systematic study of host-guest interactions to optimize framework design.
- Performance evaluation using static and dynamic adsorption experiments for vapor and aqueous phases.
- Assessment of selectivity, retention efficiency, reusability, and scalability in real-water systems.
Main Results:
- The developed COFs exhibit high bromine sorption capacities (5.16 g g-1 in vapor, 8.79 g g-1 in aqueous phase).
- Fast adsorption kinetics, high distribution coefficient (Kd ~105 mL g-1), and excellent reusability were achieved.
- Selective sequestration of trace bromine over iodine was demonstrated under static and dynamic conditions.
- Successful application in a continuous flow-through process using COF membranes showcased scalability and affordability.
Conclusions:
- Functionalized COFs with enhanced host-guest interactions offer a promising solution for efficient bromine sequestration.
- The developed materials overcome the limitations of conventional adsorbents, enabling safe chemical industry expansion and environmental protection.
- The COFs demonstrate potential for practical, scalable, and cost-effective bromine capture from various sources.
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