Functionalized mesoporous silicas SBA-15 for heterogeneous photocatalysis towards CECs removal from secondary urban wastewater

Author(s)

Castanheira, Bruna ^[1] ; Otubo, Larissa ^[2] ; Oliveira, Cristiano L. P. ^[3] ; Montes, Rosa ^[4] ; Quintana, Jose Benito ^[4] ; Rodil, Rosario ^[4] ; Brochsztain, Sergio ^[5] ; Vilar, Vitor J. P. ^[6] ; Teixeira, Antonio Carlos S. C. ^[1]

Affiliation

^[1] Univ Sao Paulo, Chem Syst Engn Ctr, Dept Chem Engn, Escola Politecn, Res Grp Adv Oxidat Proc AdOx, Av Prof Luciano Gualberto, Tr 3, BR-380 Sao Paulo, SP - Brazil

^[2] Nucl & Energy Res Inst IPEN, Av Prof Lineu Prestes 2242, BR-05508000 Sao Paulo, SP - Brazil

^[3] Univ Sao Paulo, Inst Phys, Rua Matao 1371, BR-05508090 Sao Paulo, SP - Brazil

^[4] Univ Santiago Compostela, Inst Res Chem & Biol Anal IAQBUS, Dept Analyt Chem Nutr & Food Sci, Constantino Candeira S-N, Santiago De Compostela 15782 - Spain

^[5] Fed Univ ABC, Av Estados 5001, BR-09210580 Santo Andre, SP - Brazil

^[6] Univ Porto, Fac Engn, Lab Separat & React Engn, Lab Catalysis & Mat LSRE LCM, Dept Chem Engn, Rua Dr Roberto Frias, P-4200465 Porto - Portugal

• Document type: Journal article
• Source: Chemosphere; v. 287, n. 1 JAN 2022.
• Web of Science Citations: 0

Abstract

The photocatalytic activity of TiO2 nanoparticles (NPs) supported on mesoporous silica SBA-15 (TiO2/SBA-15) was evaluated for the photodegradation of sulfadiazine (SDZ), as target contaminant of emerging concern (CEC), using either pure water solutions (PW) or a real secondary urban wastewater (UWW) spiked with SDZ. For this purpose, TiO2/SBA-15 samples with 10, 20 and 30% TiO2 (w/w) were prepared by the sol-gel post synthetic method on pre-formed SBA-15, using titanium (IV) isopropoxide as a precursor. The TiO2/SBA-15 materials were characterized by HRTEM, SAXS and XRD, nitrogen adsorption isotherms and UV-vis diffuse reflectance spectroscopy. TiO2 NPs were shown to be attached onto the external surface, decorating the SBA-15 particles. The TiO2/SBA-15 catalysts were active in SDZ photodegradation using the annular FluHelik photoreactor, when irradiated with UVA light. The 30% TiO2/SBA-15 sample presented the best performance in optimization tests performed using PW, and it was further used for the tests with UWW. The photocatalytic activity of 30% TiO2/ SBA-15 was higher (56% SDZ degradation) than that of standard TiO2-P25 (32% SDZ degradation) in the removal of SDZ spiked in the UWW ({[}SDZ] = 2 mg L-1). The photodegradation of SDZ with 30% TiO2/SBA-15 eached 90% for UWW spiked with a lower SDZ concentration ({[}SDZ] = 40 mu g L-1). Aside of SDZ, a suit of 65 other CECs were also identified in the UWW sample using LC-MS spectrometry. A fast-screening test showed the heterogeneous photocatalytic system was able to remove most of the detected CECs from UWW, by either adsorption and/or photocatalysis. (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
• FAPESP's process: 16/05496-2 - Synthesis and characterization of periodic mesoporous organosilicas containing aromatic imides for applications in the energy sector
• Grantee: Sergio Brochsztain
• Support Opportunities: Regular Research Grants