Binary Mixtures of ZnO/TiO2 for Solar Heterogeneous Photocatalysis of Non-Purgeable Organic Carbon in Landfill Leachate




Titanium dioxide; Zinc oxide; Heterogeneous photocatalysis.


Landfill leachate is a global problem that has attracted considerable attention from researchers in different areas. It is crucial to develop optimized treatment strategies for landfill leachate, given the need to minimize or eliminate negative environmental impacts resulting from the inadequate disposal of solid waste, as determined by legislation. Landfill leachate is primarily composed of humic substances, which may associate with other toxic molecules and are recalcitrant to the conventional treatments used in Brazil. This study assessed the photocatalytic degradation of carbonaceous materials in leachate collected from the Cachoeira Paulista municipal landfill, São Paulo State, Brazil. Sunlight was used as energy source without additional light inputs. Experiments were carried out in a thin-film fixed-bed reactor, using metal plates coated with paints formulated for this purpose. Paints had a low additives loading, including that of photocatalysts. We investigated the photocatalytic behavior of the binary system ZnO/TiO2 incorporated into acrylic varnish in the degradation of non-purgeable organic carbon (NPOC) in samples of humic acids and fulvic acids + humins. Reactions were conducted under acidic, neutral, or alkaline conditions. NPOC degradation was low in fulvic acid + humin samples, regardless of photocatalyst concentration or pH. The proposed process resulted in high degradation of humic acids, especially under conditions of low chemical stability, which facilitated oxidation. A maximum humic acid degradation of 65% was achieved using high concentrations of TiO2 in acidic medium.

Author Biographies

Nicoly Milhardo Lourenço Nohara, University of São Paulo

Master in Science from the Postgraduate Program in Chemical Engineering at the Engineering of Lorena/USP (2018-2021). The subject of the dissertation heterogeneous photocatalysis of recalcitrant organic compounds contained in landfill leachate. During this period, she participated as an intern in the Teaching Initiation Program in the discipline of Materials Science and Engineering. She holds a Bachelor's Degree in Environmental and Sanitary Engineering from the University of Taubaté (2012-2016). During her graduation, she was a Scientific Initiation Scholar (a) in a project on bioaccumulation of metals in algae (PIC / UNITAU) and (b) in a project on materials absorbing electromagnetic radiation (PIBIC / CNPq). She also participated in an Extension Project on the elaboration of the Management Plan for the Municipal Park of Itaim (Taubaté-SP), in addition to doing a teaching internship in the subject of Calculus. The final graduation work involved a literature review on processes for obtaining biomethane for injection into the distribution network. Between 2010 and 2011, she took a Technical course in the Environment at ETEC in São Sebastião and developed an anaerobic biodigester for the production of biogas as a conclusion.

Helcio José Izário Filho, University of São Paulo

Graduated in Chemical Engineering from the Faculty of Chemical Engineering of Lorena (1985), Master's in Materials Engineering from the Faculty of Chemical Engineering of Lorena (1993) and Ph.D. in Chemistry from the State University of Campinas (1999). He is currently a professor at the School of Engineering of Lorena-EEL / USP, with PQ-2 Research Productivity. Has experience in Chemistry, with an emphasis on Analytical Instrumentation, specifically in atomic absorption and emission spectrometry and spectrophotometry, acting on the following topics: inorganic characterization and environment (analytical characterization of solid and liquid waste and Advanced Oxidative Processes).

Marco Aurélio Kondracki de Alcântara, University of São Paulo

Marco Aurélio Kondracki de Alcântara studied Agronomic Engineering at the Federal University of Rio Grande do Sul - UFRGS. Has a Masters in Soil Sciences also at UFRGS, a Doctorate in Agricultural Engineering at the State University of Campinas - FEAGRI-UNICAMP and Post-doctorate at the Center for Research and Development of Soils and Agro-environmental Resources of the Agronomic Institute of Campinas - IAC-CPDSRA. Areas of expertise: waste treatment by advanced oxidative processes and soil pollution. He also works in the area of soil pollution. Currently, is he a Professor at the School of Engineering of Lorena at the University of São Paulo? EEL-USP, where he teaches courses in Soil, Basic Ecology and Environmental Engineering. In School at Colégio Técnico de Lorena, he teaches Biology subjects. Is he currently a Member of the Environmental Engineering Course Committee - CoC-EA, as Substitute for the Course Coordination.

Gabriel Caracciolo Koenigkam de Oliveira, University of São Paulo

He is currently a Technician at the Laboratory of Spectrophotometry at the School of Engineering of Lorena - USP. He has a background in Chemistry.

Fernando Vernilli Junior, University of São Paulo

Post Doctorate from UFSCar, Doctor in Chemistry from UNESP, Master in Materials Engineering and Chemical Engineer from EEL-USP. Associate Professor, Vice Mayor of the USP Campus in Lorena and CNPq Productivity Scholarship in Technological Development and Innovation. He was President of the Graduate Committee at EEL-USP for 3 terms, and also Coordinator of the Graduate Program in Materials Engineering at EEL-USP for 2 terms. He has over 35 years of experience in the development and characterization of ceramic materials. Acting in the synthesis of raw materials by hydrometallurgy and development of new ceramic materials, mainly refractories for the metallurgical sector, conducting research on modern techniques in the reuse of waste generated in the steel industry.

Evandro Luís Nohara, University of Taubaté

Graduated in Technological Chemistry from Universidade Estadual Paulista Júlio de Mesquita Filho (1996), Master's from Instituto Tecnológico de Aeronáutica (1998) and Doctorate Sandwich from Instituto Tecnológico de Aeronáutica and Moscow Power Engineering Institute (2003). He has been a professor at the Department of Mechanical Engineering at the University of Taubaté since 2003, where he has been teaching for undergraduate and postgraduate courses in materials sciences, and in the execution of R&D projects in the area of Materials Engineering and Aerospace Engineering, working in the following areas. topics: processing and characterization of structural polymer composites, electromagnetic radiation absorbing materials and nanotechnology. He has been an Honorary Member of the Brazilian Air Force since 2008. He is the current Coordinator of the Professional Master's Program in Mechanical Engineering at the University of Taubaté.

Kleberson Aristogenio de Oliveira, University of Taubaté

Kleberson Aristogenio de Oliveira has basic training: Aeronautical Engineering from the University of Taubaté - UNITAU and Technician in Informatics from ETEC de Cruzeiro. His professional experience includes approximately six years as a Tool Adjuster at IOCHPE Maxion S/A, ten months as an intern at the Materials and Mechanical Testing Laboratory - UNITAU, and ten months as a Senior Monitor, in the disciplines: Technology of metallic aeronautical materials and Materials technology composite aeronautics, at the University of Taubaté. He is currently studying for a Master's Degree in Mechanical Engineering at the University of Taubaté.

Marcos Fernandes de Oliveira, Oswaldo Cruz Faculties

Ph.D. degree in Materials Engineering at Polytechnic School of the University of São Paulo, Brazil (2006). Graduated in Industrial Chemist in 1990 at Guarulhos University, São Paulo, Brazil. Specialist Chemist for DuPont do Brasil, during 29 years researching OEM coatings for car manufacturers (Toyota, Honda, Mitisubishi, Volvo, General Motors, Volkswagen and Ford). In 2002 and 2003, received the DuPont Safety Health Environment Prize for projects to reduce the volatile organic content in OEM coatings. In 2004, 2006, 2010 and 2017 received the 9th, 10th, 12th and 18th Science and Technology Coatings Award from Brazilian Paint Manufacturers Association (ABRAFATI) for works with organosilanes to reduce the corrosion rate in automotive carbon steel, carbon black pigments studies to avoid corrosion in steel tanks, magnesium oxide as ecological corrosion inhibitor, and nanoceramic as pretretament, respectively. Professor of Materials Science (Cure Mechanisms of Polymeric Films) for Coatings Technology Post graduation Course - Oswaldo Cruz College, São Paulo Brazil


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How to Cite

NOHARA, N. M. L.; IZÁRIO FILHO, H. J.; ALCÂNTARA, M. A. K. de; OLIVEIRA, G. C. K. de; VERNILLI JUNIOR, F.; NOHARA, E. L.; OLIVEIRA, K. A. de; OLIVEIRA, M. F. de. Binary Mixtures of ZnO/TiO2 for Solar Heterogeneous Photocatalysis of Non-Purgeable Organic Carbon in Landfill Leachate. Research, Society and Development, [S. l.], v. 11, n. 6, p. e48411624570, 2022. DOI: 10.33448/rsd-v11i6.24570. Disponível em: Acesso em: 24 may. 2022.