Phosphonium-Crosslinked Chitosan (PCC)

BACKGROUND 

Researchers at the University of Calgary have developed a non-toxic adsorbent material, phosphonium-crosslinked chitosan (PCC), for the removal of heavy metal ions from water. This invention uses a one-step chemical reaction to incorporate a low-cost phosphonium salt to the polymer.

Heavy metal-ions, such as hexavalent chromium (Cr(VI)), are extremely hazardous to humans, animals, and the environment and as such, the World Health Organization mandated a maximum allowable concentration of these heavy metal-ions in water. Heavy metal-ions are produced by a variety of processes used in industry.

Adsorption is a commonly used method for treating water and wastewater streams containing heavy metal-ions, and most adsorbents for heavy metal-ions, including Cr(VI), and other anions, rely on nitrogen-based functional groups. Industrially, synthetic polymers are often used rather than naturally occurring materials for adsorbing heavy metal-ions due to their greater adsorption capacities. Production of synthetic polymer-based adsorbents itself produces undesirable wastes and increases the carbon footprint.

AREAS OF APPLICATION

• Removal of heavy metal-ions, such as hexavalent chromium (Cr(VI)), from a solution.
• Water and wastewater treatment.

COMPETITIVE ADVANTAGES

• PCC is an environmentally friendly biomass-based adsorbent.
• Chitosan is non-toxic and readily available.
• A one-step chemical reaction for production.
• Cost-effective method of production.

PUBLICATIONS AND RESOURCES

• Patent publication: US10538598B2
• Journal publication: Sessarego S et al. (2019). Phosphonium-enhanced chitosan for Cr(VI) adsorption in wastewater treatment. Carbohydrate Polymers 211: 249-256.
• Researcher profile: Dr. Josephine Hill