TY - JOUR
T1 - Compact light-emitting diode optical fiber immobilized TiO2 reactor for photocatalytic water treatment
AU - O'Neal Tugaoen, Heather
AU - GARCIA SEGURA, Sergio
AU - Hristovski, Kiril
AU - Westerhoff, Paul
N1 - Publisher Copyright:
© 2017 Elsevier B.V.
PY - 2018/2/1
Y1 - 2018/2/1
N2 - A key barrier to implementing photocatalysis is delivering light to photocatalysts that are in contact with aqueous pollutants. Slurry photocatalyst systems suffer from poor light penetration and require post-treatment to separate the catalyst. The alternative is to deposit photocatalysts on fixed films and deliver light onto the surface or the backside of the attached catalysts. In this study, TiO2-coated quartz optical fibers were coupled to light emitting diodes (OF/LED) to improve in situ light delivery. Design factors and mechanisms studied for OF/LEDs in a flow-through reactor included: (i) the influence of number of LED sources coupled to fibers and (ii) the use of multiple optical fibers bundled to a single LED. The light delivery mechanism from the optical fibers into the TiO2 coatings is thoroughly discussed. To demonstrate influence of design variables, experiments were conducted in the reactor using the chlorinated pollutant para-chlorobenzoic acid (pCBA). From the degradation kinetics of pCBA, the quantum efficiencies (Φ) of oxidation and electrical energies per order (EEO) were determined. The use of TiO2 coated optical fiber bundles reduced the energy requirements to deliver photons and increased available surface area, which improved Φ and enhanced oxidative pollutant removal performance (EEO).
AB - A key barrier to implementing photocatalysis is delivering light to photocatalysts that are in contact with aqueous pollutants. Slurry photocatalyst systems suffer from poor light penetration and require post-treatment to separate the catalyst. The alternative is to deposit photocatalysts on fixed films and deliver light onto the surface or the backside of the attached catalysts. In this study, TiO2-coated quartz optical fibers were coupled to light emitting diodes (OF/LED) to improve in situ light delivery. Design factors and mechanisms studied for OF/LEDs in a flow-through reactor included: (i) the influence of number of LED sources coupled to fibers and (ii) the use of multiple optical fibers bundled to a single LED. The light delivery mechanism from the optical fibers into the TiO2 coatings is thoroughly discussed. To demonstrate influence of design variables, experiments were conducted in the reactor using the chlorinated pollutant para-chlorobenzoic acid (pCBA). From the degradation kinetics of pCBA, the quantum efficiencies (Φ) of oxidation and electrical energies per order (EEO) were determined. The use of TiO2 coated optical fiber bundles reduced the energy requirements to deliver photons and increased available surface area, which improved Φ and enhanced oxidative pollutant removal performance (EEO).
KW - Advanced oxidation processes
KW - Nanotechnology
KW - Photocatalysis
KW - Trace organics, pollutants
KW - Water treatment
UR - http://www.scopus.com/inward/record.url?scp=85030109545&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85030109545&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2017.09.242
DO - 10.1016/j.scitotenv.2017.09.242
M3 - Article
AN - SCOPUS:85030109545
SN - 0048-9697
VL - 613-614
SP - 1331
EP - 1338
JO - Science of the Total Environment
JF - Science of the Total Environment
ER -