Preservatives degradation: coupling processes, organic interfering effect and scale-up

• Grant number: 16/19662-1
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• Start date: January 30, 2017
• End date: January 29, 2018
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Artur de Jesus Motheo
• Grantee: Dawany Dionisio
• Supervisor: Manuel Andrés Rodrigo Rodrigo
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Institution abroad: Universidad de Castilla-La Mancha, Ciudad Real (UCLM), Spain
• Associated to the scholarship: 16/04825-2 - Effect of interferents and operational features on the degradation of endocrine disruptors, BP.DD

Abstract

Parabens are preservatives, widely used in health and personal care products. After studies relating these compounds to human breast tumors, they were classified as endocrine disrupting chemicals. Usually, preservatives are commercialized as blends and parabens are often mixed with diazolidinyl urea (DU) and propylene glycol (PG). These substances are not completely removed from water by conventional wastewater treatment and several alternative processes have been developed. Electrochemical methods (ECh) have proved to be efficient in oxidizing organic contaminants. To improve these results, several coupled processes have been studied, such as Fenton, photochemical and, most recently, sonochemical (SCh) technologies. The aim of this project is to couple/combine ECh with SCh methods, using different operational features, and evaluating their influence on methyl paraben (MeP) removal. Considering that most degradation studies use isolated compounds, it is also important to evaluate the interference effect of DU and PG on MeP oxidation, that aims to simulate a real wastewater medium. The studies will be carried out in bench and pilot scale, using a boron-doped diamond electrode. By using chromatography and total organic carbon (TOC) analysis, degradations will be evaluated by MeP and TOC removal, current efficiency and energy consumption. The coupling process may improve removal of contaminants, but may not necessarily result in a better mineralization. Moreover, ultrasound can be combined with ECh processes using a number of systems, which may produce different effects on the oxidation mechanism, reflected in process efficiency. (AU)

Scientific publications

(6)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

DIONISIO, D.; MOTHEO, A. J.; SAEZ, C.; RODRIGO, M. A.. Effect of the electrolyte on the electrolysis and photoelectrolysis of synthetic methyl paraben polluted wastewater. Separation and Purification Technology, v. 208, n. SI, p. 201-207, JAN 8 2019. (16/04825-2, 16/19662-1)

DIONISIO, DAWANY; MOTHEO, ARTUR J.; SAEZ, CRISTINA; CANIZARES, PABLO; RODRIGO, MANUEL A.. Competitive Anodic Oxidation of Methyl Paraben and Propylene Glycol: Keys to Understand the Process. CHEMELECTROCHEM, v. 6, n. 3, p. 771-778, FEB 1 2019. (16/04825-2, 16/19662-1)

DIONISIO, DAWANY; MOTHEO, ARTUR J.; SAEZ, CRISTINA; CANIZARES, PABLO; RODRIGO, MANUEL A.. Coupling Ultrasound to the Electro-Oxidation of Methyl Paraben Synthetic Wastewater: Effect of Frequency and Supporting Electrolyte. CHEMELECTROCHEM, v. 6, n. 4, p. 1199-1205, FEB 15 2019. (16/04825-2, 16/19662-1)

DIONISIO, DAWANY; RODRIGO, MANUEL A.; MOTHEO, ARTUR J.. Electrochemical degradation of a methyl paraben and propylene glycol mixture: Interference effect of competitive oxidation and pH stability. Chemosphere, v. 287, n. 3, JAN 2022. (17/10118-0, 16/19662-1, 16/04825-2, 17/20444-1)

DIONISIO, D.; MOTHEO, A. J.; SAEZ, C.; RODRIGO, M. A.. Effect of the electrolyte on the electrolysis and photoelectrolysis of synthetic methyl paraben polluted wastewater. Separation and Purification Technology, v. 208, p. 7-pg., 2019-01-08. (16/04825-2, 16/19662-1)

DIONISIO, DAWANY; SANTOS, LUCAS H. E.; RODRIGO, MANUEL A.; MOTHEO, ARTUR J.. Electro-oxidation of methyl paraben on DSA (R)-Cl-2: UV irradiation, mechanistic aspects and energy consumption. Electrochimica Acta, v. 338, APR 1 2020. (16/04825-2, 17/20444-1, 16/19662-1, 17/10118-0)