Water Resources Research Act Program

Details for Project ID 2017PR177B

Atrazine degradation with visible-light photocatalysis using iron-grafted TiO2 nanoparticles: Evaluation and applications for water treatment

Institute: Puerto Rico
Year Established: 2017 Start Date: 2017-03-01 End Date: 2018-02-28
Total Federal Funds: $20,000 Total Non-Federal Funds: $32,890

Principal Investigators: Pedro Tarafa, OMarcelo Suarez, Sylvia RodriguezAbudo

Abstract: The indiscriminate use of pesticides for agriculture has resulted in the presence of a variety of persistent contaminants in surface and ground waters, which compromise the water quality of these sources. An example of this is atrazine (ATZ), which is a herbicide that is widely used by farmers and is of particular concern due to its relatively long half-life and low adsorption in soils. In addition, it is a potent endocrine disruptor and has been associated to human reproductive disorders and birth effects. Recent studies have evaluated the degradation of various organic pollutants by photocatalysis, using wide band gap semiconductors to promote advanced oxidation processes (AOPs). One of those appealing alternative photocatalytic compounds is titanium dioxide (TiO2). However, TiO2 usage has a few shortcomings; for instance, TiO2 can be excited only under UV light irradiation with wavelengths shorter than 400 nm. One strategy to overcome this limitation is by doping the bulk phase of TiO2 with various metal ions. This modification has shown remarkable visible light absorption efficiency and enhancement of photocatalytic activity. Among a list of transition metal ions evaluated, Fe(III) has shown to be one of the most reactive. The present study focused on assessing the viability of Fe(III)TiO2 nanoparticles to effectively photodegrade ATZ in water solutions under the influence of visible light. Our goal is to develop and implement a water treatment process consisting of gravity-influenced inclined plane impregnated with iron-grafted TiO2 nanoparticles for the degradation of pesticide-related contaminants under the influence of sun light via photodegradation. To accomplish and complete this endeavor, it is proposed a two-year project encompassing four main phases: 1) chemical modification of the TiO2 surface; 2) viability of Fe(III)-TiO2 for photodegradation of ATZ; 3) immobilization of Fe(III)-TiO2 nanoparticles in the PVC matrix; and 4) design, construction and evaluation of a lab-scale inclined plane for effective photodegradation of ATZ under the influence of visible light. The realization of this project will provide essential data to set the foundations for the development and establishment of an easy-to-use, energy-efficient water treatment process for the removal/destruction of pesticides-related contaminants in water.