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Sorption of Aromatic Compounds with Copolymer Sorbent Materials Containing β-Cyclodextrin
Lee D Wilson1, Mohamed H Mohamed2, Christopher L Berhaut3
1Department of Chemistry, 110 Science Place (Rm. 156), University of Saskatchewan, Saskatoon, SK S7N 5C9, Canada. lee.wilson@usask.ca.
Materials (Basel, Switzerland)
|August 22, 2017
Summary
New urethane copolymers with β-cyclodextrin (CD) show promise for removing chlorinated organic pollutants. These CD-based sorbents offer an alternative to granular activated carbon (GAC) for water purification.
Area of Science:
- Polymer Chemistry
- Environmental Science
- Materials Science
Background:
- Chlorinated aromatic compounds are persistent environmental pollutants.
- Effective sorbent materials are needed for their removal from water.
- β-cyclodextrin (CD) incorporation can enhance sorbent properties.
Purpose of the Study:
- To synthesize and characterize urethane copolymers incorporating β-cyclodextrin (CD).
- To evaluate the sorption properties of these copolymers for chlorinated aromatic compounds.
- To compare their performance against granular activated carbon (GAC).
Main Methods:
- Preparation of MDI-X and CDI-X urethane copolymers with β-cyclodextrin.
- Sorption experiments in aqueous solutions at variable pH.
- Measurement of BET surface areas for sorbents.
- Quantification of sorption capacities for pentachlorophenol, 2,4-dichlorophenol, and 2,4-dichlorophenoxy acetic acid.
Main Results:
- Copolymers exhibited lower BET surface areas ( < 10¹ m²/g) compared to GAC (~10³ m²/g).
- Sorption capacities followed the order: GAC > CDI-3 copolymer ≈ MDI-3 copolymer.
- Sorption affinity for adsorbates was: 2,4-dichlorophenol > 2,4-dichlorophenoxy acetic acid > pentachlorophenol.
Conclusions:
- Urethane copolymer sorbents incorporating β-cyclodextrin demonstrate effective sorption of chlorinated organics.
- Sorbent performance is influenced by surface area, CD content/accessibility, and material chemistry.
- These novel copolymers present a viable alternative to GAC for specific environmental remediation applications.
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