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Mater Sci Nanotechnol 2017 | Volume 1 Issue 2
allied
academies
Nanomaterials and Nanochemistry
November 29-30, 2017 | Atlanta, USA
International Conference on
Assessment of the production of hydroxyl radical using nano zero-valent iron embedded in a meso-
porous silica matrix
Steven Huezo
Desert Research Institute, USA
Z
ero-Valent Iron (Fe0) has been shown to detoxify
water by creating hydroxyl radicals through Fenton-like
reactions combined with hydrogen peroxide (H
2
O
2
) to get
rid of organic contaminants. Nano-sized zero-valent iron
(n/ZVI) in combination with oxidants and UV radiation, has
been reported can increase the Fenton reaction rate and
make water detoxification more effective. In this work, the
production of reactive oxygen species, particularly hydroxyl
radicals, was assessed for the heterogeneous photo-assisted
Fenton-like reaction using nZVI embedded in a mesoporous
silica matrix, hydrogen peroxide, and UV-A radiation. The
experiments consisted of preparing a 10 µM solution of
N, N-dimethyl-p-nitroaniline (pNDA, used as HO• radical
probe) in 100 mL of water and adding the silica-embedded
nZVI at three different loads (please include loads of Zvi in
the SBA-15) with or without H
2
O
2
, and/or UV-A radiation
(λmax=365 nm). The absorbance of the pNDA was measured
and compared to that of clear, deionized water. The trials
consisted of using immobilized nZVI alone, immobilized nZVI/
H
2
0
2
, and immobilized nZVI/H
2
0
2
/UV. From the experimental
results, we have seen that the best conditions for hydroxyl
radicals production measured as pNDA bleaching are by the
combination of immobilized nZVI/H
2
O
2
/UV despite nZVI,
UV-A radiation and hydrogen peroxide alone were capable
of bleaching pNDA to a certain extent. The use of the H
2
O
2
/
UV system reached a plateau in hydroxyl radical production
after 20 min of reaction. Two kinetic models are proposed
to fit experimental data for the different reaction conditions
tested and the obtained results were capable of fitting
experimental data fairly good meaning that the proposed
reaction mechanisms may occur within the reaction mixture
to someextent. This novelmaterial foundwaswith interesting
capabilities to produce reactive oxygen species, particularly
hydroxyl radicals, under photo assisted conditions and high
potential for further photocatalytic applications in water
treatment.
Speaker Biography
Steven Huezo Pineda is an assistant researcher working with Erick Bandala at Desert
Research Institute in Las Vegas, Nevada. He is an undergrad majoring in Biochemistry
at the University of Nevada, Las Vegas. He has been working at DRI (Desert Research
Institute) since January, focusing on Zero-Valent Iron and using it to clean pollutants
of water. Steven Huezo will plan to continue his work next year, working with the
Department of Energy to clean chlorine from groundwater.
e:
huezo@unlv.nevada.edu