Brass corrosion in chlorinated tap water inhibited by phosphate ions

Authors
Yohai del Cerro, Lucía; Schreiner, W. H.; Vazquez, Marcela Vivian; Valcarce, María Beatriz
Publication Year
2015
Language
English
Format
article
Status
Published version
Description
The combined effect of phosphate ions as corrosion inhibitor and sodium hypochlorite as biocide is studied on aluminum brass in contact with artificial tap water. The interaction between phosphates and hypochlorite was evaluated by electrochemical techniques for films formed between 2 and 192 h and by weight loss tests for immersion times of 90 days. Raman spectroscopy and X-ray photoelectron spectroscopy were used to study the passive layer. When the biocide agent is present, dezincification is the predominant form of localized corrosion after long time exposures. When the inhibitor is present a nobler pitting potential was found. EIS results suggest the development of a compact passive layer, regardless of the presence of the biocide. No localized attack was detected on samples immersed for 90 days at open circuit potential in the presence of phosphates, even when NaClO is present. Weight loss analysis showed inhibit ion efficiencies higher than 90% when phosphates and the biocide are present. The oxidative nature of NaClO could favor Zn dissolution and enhance the precipitation of Zn3(PO4)2 layer, producing a more compact surface layer.
Fil: Yohai del Cerro, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina
Fil: Schreiner, W. H.. Universidade Federal do Paraná; Brasil
Fil: Vazquez, Marcela Vivian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina
Fil: Valcarce, María Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina
Subject
Aluminum brass
Phosphate
Corrosion inhibition
Sodium hypochlorite
Otras Ciencias Químicas
Ciencias Químicas
CIENCIAS NATURALES Y EXACTAS
Físico-Química, Ciencia de los Polímeros, Electroquímica
Ciencias Químicas
CIENCIAS NATURALES Y EXACTAS
Access level
Restricted access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/29570