Buoyant Photocatalytic Materials for Water Remediation [Hybrid Poster 3-B]

Kayla Steward, Western Kentucky University

Abstract

Buoyant Photocatalytic Materials for Water Remediation

J.R Betram, Kayla Steward, Matthew Nee, Chemistry

In early 2014 nearly 300,000 people were without potable water in western West Virginia due to a catastrophic spill that occurred in the Elk River, releasing 7,500 gallons of toxic compounds including 4-methylcyclohexanemethanol (MCHM) whose post-exposure long-term effects are still unknown. MCHM was even detected around northern Kentucky in the Ohio river shortly after the spill, where the city of Louisville derives a majority of its drinking water. Unfortunately, there was no formidable treatment method in place to remove MCHM from any natural body of water. Using the sun as a renewable source of energy, photocatalysts, such as titanium dioxide (TiO2), absorb the sun’s incident photons and successively break down microorganisms, organic compounds, crude oil, and many other pollutants. In theory they are ideal candidates for water remediation in crises such as this, but unfortunately the use of photocatalysts alone is not possible because of their high density. This causes sedimentation of the photocatalyst posing two major problems; their post-treatment recovery is almost impossible, and preclusion of degradation would occur because the insoluble contaminants reside on top of the water. A solution that effectively uses photocatalysts for water remediation is to embed the photocatalyst into a buoyant supporting material. Polydimethylsiloxane (PDMS) is a low-cost and environmentally inert polymer that becomes buoyant under a processing technique used in our lab to fabricate PDMS beads. In this project, TiO2 is embedded into micro-structured PDMS beads to create buoyant photocatalytic materials for use in water remediation. Methylene blue (MB) is an organic dye found in many industrial waste streams and is a standard target for photocatalytic degradation. The TiO2/PDMS beads produced in our lab were able to completely remove substantial concentrations of MB from water in 80 minutes. The creation of buoyant supporting material for photocatalysts provides a clean and cost-effective way to remove harmful contaminants from natural bodies of water.

 

Buoyant Photocatalytic Materials for Water Remediation [Hybrid Poster 3-B]

Buoyant Photocatalytic Materials for Water Remediation

J.R Betram, Kayla Steward, Matthew Nee, Chemistry

In early 2014 nearly 300,000 people were without potable water in western West Virginia due to a catastrophic spill that occurred in the Elk River, releasing 7,500 gallons of toxic compounds including 4-methylcyclohexanemethanol (MCHM) whose post-exposure long-term effects are still unknown. MCHM was even detected around northern Kentucky in the Ohio river shortly after the spill, where the city of Louisville derives a majority of its drinking water. Unfortunately, there was no formidable treatment method in place to remove MCHM from any natural body of water. Using the sun as a renewable source of energy, photocatalysts, such as titanium dioxide (TiO2), absorb the sun’s incident photons and successively break down microorganisms, organic compounds, crude oil, and many other pollutants. In theory they are ideal candidates for water remediation in crises such as this, but unfortunately the use of photocatalysts alone is not possible because of their high density. This causes sedimentation of the photocatalyst posing two major problems; their post-treatment recovery is almost impossible, and preclusion of degradation would occur because the insoluble contaminants reside on top of the water. A solution that effectively uses photocatalysts for water remediation is to embed the photocatalyst into a buoyant supporting material. Polydimethylsiloxane (PDMS) is a low-cost and environmentally inert polymer that becomes buoyant under a processing technique used in our lab to fabricate PDMS beads. In this project, TiO2 is embedded into micro-structured PDMS beads to create buoyant photocatalytic materials for use in water remediation. Methylene blue (MB) is an organic dye found in many industrial waste streams and is a standard target for photocatalytic degradation. The TiO2/PDMS beads produced in our lab were able to completely remove substantial concentrations of MB from water in 80 minutes. The creation of buoyant supporting material for photocatalysts provides a clean and cost-effective way to remove harmful contaminants from natural bodies of water.