IDEAS home Printed from https://ideas.repec.org/a/gam/jsusta/v17y2025i18p8491-d1755054.html
   My bibliography  Save this article

Upcycling Anodic Sludge from Aluminum Anodizing: Leaching Efficiency and Thermal Conversion into Refractory Materials

Author

Listed:
  • Fausto Acosta

    (Department of Extractive Metallurgy, Escuela Politécnica Nacional, Ladrón de Guevara E11-253, Quito 170525, Ecuador)

  • Cristhian Feijoo

    (Instituto de Investigación Geológico y Energético (IIGE), Quito 170518, Ecuador)

  • Alfredo S. Sangurima-Cedillo

    (Department of Extractive Metallurgy, Escuela Politécnica Nacional, Ladrón de Guevara E11-253, Quito 170525, Ecuador)

  • Alicia Guevara

    (Department of Extractive Metallurgy, Escuela Politécnica Nacional, Ladrón de Guevara E11-253, Quito 170525, Ecuador)

  • Carlos F. Aragón-Tobar

    (Department of Extractive Metallurgy, Escuela Politécnica Nacional, Ladrón de Guevara E11-253, Quito 170525, Ecuador)

Abstract

Anodic sludges generated in the production of aluminum profiles pose both an environmental and economic problem due to their accumulation in municipal landfills. This study investigates their valorization as a raw material for industry through leaching and calcination processes. The solid residue was characterized both physically and chemically. In the leaching process, concentrations of NaOH (1–2.5 M) and solid percentages (10–30%) were evaluated, achieving a 93.7% recovery of aluminum as sodium aluminate with 2 M NaOH and 10% solids. In the calcination process, the sludges were treated at temperatures ranging from 200 to 1600 °C, and different particle sizes (−3 + 1 mm, −1000 + 400 μm, −400 + 200 μm). The best result from calcination was obtained at 1600 °C, producing a refractory material composed of corundum (α-Al 2 O 3 ) and diaoyudaoite (NaAl 11 O 17 ).

Suggested Citation

  • Fausto Acosta & Cristhian Feijoo & Alfredo S. Sangurima-Cedillo & Alicia Guevara & Carlos F. Aragón-Tobar, 2025. "Upcycling Anodic Sludge from Aluminum Anodizing: Leaching Efficiency and Thermal Conversion into Refractory Materials," Sustainability, MDPI, vol. 17(18), pages 1-16, September.
    • Handle: RePEc:gam:jsusta:v:17:y:2025:i:18:p:8491-:d:1755054
    as

    Download full text from publisher

    File URL: https://www.mdpi.com/2071-1050/17/18/8491/pdf
    Download Restriction: no
    File URL: https://www.mdpi.com/2071-1050/17/18/8491/
    Download Restriction: no
    ---><---

    More about this item

    Keywords

    ;
    ;
    ;

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:gam:jsusta:v:17:y:2025:i:18:p:8491-:d:1755054. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    We have no bibliographic references for this item. You can help adding them by using this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: MDPI Indexing Manager (email available below). General contact details of provider: https://www.mdpi.com .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.