| Full text | |
| Author(s): |
de Araujo Gusmao, Carolina
[1]
;
Palharim, Priscila Hasse
[1]
;
Ramos, Bruno
[1, 2]
;
Teixeira, Antonio Carlos Silva Costa
[1]
Total Authors: 4
|
| Affiliation: | [1] Univ Sao Paulo, Dept Chem Engn, Escola Politecn, Res Grp Adv Oxidat Proc AdOx, Av Prof Luciano Gualberto, Tr 3, BR-380 Sao Paulo, SP - Brazil
[2] Univ Sao Paulo, Escola Politecn, Dept Met & Mat Engn, Av Prof Luciano Gualberto, Tr 3, BR-380 Sao Paulo, SP - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | Environmental Science and Pollution Research; OCT 2021. |
| Web of Science Citations: | 0 |
| Abstract | |
Catalyst samples based on SiO2-supported TiO2 were prepared with the incorporation of Ag (metal), S (nonmetal), and ZnO@S (semiconductor and nonmetal). The materials were evaluated regarding their morphological, optical, and crystalline properties as well as their photoactivity under visible and ultraviolet light toward the degradation rate of a model emerging pollutant, acetaminophen (ACT). All modified materials exhibited improved performance over the undoped catalyst. The Ag-doped catalyst achieved the largest degradation under visible radiation (about 30% in 120 min), whereas under ultraviolet irradiation, the ZnO@S-doped sample exhibited the best performance (about 62% in 120 min). A Doehlert design was carried out to evaluate the influence of pH and temperature on the photoactivity of Ag-TiO2/SiO2. In addition, the role of each reactive species in the photodegradation reaction was investigated by radical scavenger experiments, and the superoxide radical anion O-2(center dot-) was shown to be the predominant reactive species. The stability of the Ag-TiO2/SiO2 material under ultraviolet and visible light was confirmed after five successive operation cycles, showing a reasonable (about 50%) loss of activity under visible irradiation and a slight improvement (about 13%) under UV light, as a result of the photo-reduction of Ag+. Lastly, the effect of the initial pollutant concentration showed that ACT degradation using Ag-TiO2/SiO2 follows the Langmuir-Hinshelwood kinetics, with intrinsic reaction rate k = 2.71 x 10(-4) mmol L-1 min(-1) under visible-light radiation. (AU) | |
| FAPESP's process: | 18/21271-6 - SOLAR DEGRADATION OF POLLUTANTS OF EMERGING CONCERN: PHOTOREACTORS AND INNOVATIVE TREATMENTS |
| Grantee: | Antonio Carlos Silva Costa Teixeira |
| Support Opportunities: | Regular Research Grants |