Title

The effect of UV exposure on TiO2 nanomaterials reduction of p-chlorobenzoic acid concentration in aqueous solutions through photocatalysis

Author(s)

Erin Blalock, SVHS

School Name

Spring Valley High School

Grade Level

11th Grade

Presentation Topic

Environmental Science

Presentation Type

Non-Mentored

Oral Presentation Award

4th Place

Written Paper Award

3rd Place

Abstract

Titanium dioxide (nTiO2) displays photocatalytic properties which are derived from the production of hydroxyl radicals which oxidize nearby organic molecules on the TiO2 surface. A specific micropollutant, p-chlorobenzoic acid (pCBA) is a potential indicator of radical production in the photocatalysis. This experiment determined the photocatalytic ability of TiO2, through measurements of absorbance and concentration of pCBA remaining after 30 min interval. The study investigated the effects of a UV light on the photocatalytic ability of TiO2, as well as whether or not photocatalytic oxidation caused by UV light occurs in TiO2 and pcb aqueous solutions. It was hypothesized that if TiO2 nanomaterials are placed in 4- chlorobenzoic acid in varying amounts of UV light illumination, then the TiO2 exposed to higher amounts of UV illumination will lower absorbance indicating an increased production of hyper-reactive hydroxyl radicals that attack the the micropollutant p-chlorobenzoic acid (pCBA), and a decreased concentration of p-chlorobenzoic acid (pCBA). The amount of pCBA remaining was determined by the absorbance proportion multiplied by 15 mg of pCBA. A one-way ANOVA (α = 0.05 (F(2, 24) = 1.55, p < 0.05) and an equal variance, demonstrated that there was no significant difference between the adsorption of the non UV exposed pCBA containing TiO2 and the control, however there was a significant difference between those two groups and the UV exposed pCBA containing TiO2. These results indicate that TiO2 when treated with UV light, effectively reduces the concentrations of pCBA.

Location

Lassiter 220

Start Date

4-14-2018 11:15 AM

Presentation Format

Oral and Written

COinS
 
Apr 14th, 11:15 AM

The effect of UV exposure on TiO2 nanomaterials reduction of p-chlorobenzoic acid concentration in aqueous solutions through photocatalysis

Lassiter 220

Titanium dioxide (nTiO2) displays photocatalytic properties which are derived from the production of hydroxyl radicals which oxidize nearby organic molecules on the TiO2 surface. A specific micropollutant, p-chlorobenzoic acid (pCBA) is a potential indicator of radical production in the photocatalysis. This experiment determined the photocatalytic ability of TiO2, through measurements of absorbance and concentration of pCBA remaining after 30 min interval. The study investigated the effects of a UV light on the photocatalytic ability of TiO2, as well as whether or not photocatalytic oxidation caused by UV light occurs in TiO2 and pcb aqueous solutions. It was hypothesized that if TiO2 nanomaterials are placed in 4- chlorobenzoic acid in varying amounts of UV light illumination, then the TiO2 exposed to higher amounts of UV illumination will lower absorbance indicating an increased production of hyper-reactive hydroxyl radicals that attack the the micropollutant p-chlorobenzoic acid (pCBA), and a decreased concentration of p-chlorobenzoic acid (pCBA). The amount of pCBA remaining was determined by the absorbance proportion multiplied by 15 mg of pCBA. A one-way ANOVA (α = 0.05 (F(2, 24) = 1.55, p < 0.05) and an equal variance, demonstrated that there was no significant difference between the adsorption of the non UV exposed pCBA containing TiO2 and the control, however there was a significant difference between those two groups and the UV exposed pCBA containing TiO2. These results indicate that TiO2 when treated with UV light, effectively reduces the concentrations of pCBA.