Scholarlink

<p>The mitigation of metallic corrosion remains a critical socio-economic and technical challenge, necessitating the transition toward sustainable and high-performance protective materials. This study explores the valorization of jarosite—a hazardous industrial waste from zinc hydrometallurgy—as a functional pigment in organic coatings. Formulations were developed using epoxy and alkyd matrices, with jarosite concentrations maintained below the Critical Pigment Volume Concentration (CPVC ~ 30%) to ensure full polymeric encapsulation. The pigment was characterized by a polymodal particle size distribution (1.1–22&#xa0;μm) and high surface area (12.2&#xa0;m²/g), contributing to a dense packing effect. The anticorrosive performance was evaluated through Electrochemical Impedance Spectroscopy (EIS), salt spray exposure, and pull-off adhesion tests. SEM/EDS analysis revealed that the irregular prismatic morphology of jarosite crystals is consistent with the formation of a tortuous diffusion pathway, suggesting delayed electrolyte diffusion. EIS results showed that the epoxy-jarosite system maintained superior barrier properties, with low-frequency impedance modules (|Z|<sub>0.01&#xa0;Hz</sub>) remaining above 10<sup>10</sup> Ω.cm² for 5–8 wt% loadings throughout 100 days of immersion. Leaching assessments via ICP-OES revealed divergent immobilization behavior between the binder systems: while the epoxy matrix achieved effective retention of Pb and Cd below the quantification limit, the alkyd matrix exhibited a measurable release of Cd (40&#xa0;µg/L), indicating partial immobilization efficiency under highly saline conditions.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Industrial jarosite as a functional pigment in epoxy and alkyd anticorrosive coatings

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年7月13日

查看全文
  • Bárbara Mitraud Aroeira,
  • Júlia Pimenta Perdigão Vieira,
  • Beatriz Monteiro de Andrade Dias,
  • Matheus Orlandi Pessoa,
  • Fernando Cotting

摘要

The mitigation of metallic corrosion remains a critical socio-economic and technical challenge, necessitating the transition toward sustainable and high-performance protective materials. This study explores the valorization of jarosite—a hazardous industrial waste from zinc hydrometallurgy—as a functional pigment in organic coatings. Formulations were developed using epoxy and alkyd matrices, with jarosite concentrations maintained below the Critical Pigment Volume Concentration (CPVC ~ 30%) to ensure full polymeric encapsulation. The pigment was characterized by a polymodal particle size distribution (1.1–22 μm) and high surface area (12.2 m²/g), contributing to a dense packing effect. The anticorrosive performance was evaluated through Electrochemical Impedance Spectroscopy (EIS), salt spray exposure, and pull-off adhesion tests. SEM/EDS analysis revealed that the irregular prismatic morphology of jarosite crystals is consistent with the formation of a tortuous diffusion pathway, suggesting delayed electrolyte diffusion. EIS results showed that the epoxy-jarosite system maintained superior barrier properties, with low-frequency impedance modules (|Z|0.01 Hz) remaining above 1010 Ω.cm² for 5–8 wt% loadings throughout 100 days of immersion. Leaching assessments via ICP-OES revealed divergent immobilization behavior between the binder systems: while the epoxy matrix achieved effective retention of Pb and Cd below the quantification limit, the alkyd matrix exhibited a measurable release of Cd (40 µg/L), indicating partial immobilization efficiency under highly saline conditions.