Improved understanding of Sodium hydroxide concentration role and kinetic model of cryolite reactive extraction in cathode Spent Pot Linings

• Autorzy: Tropenauer Blaž , Klinar Dušan , Golob Janvit

Identyfikatory

DOI

10.2478/pjct-2021-0006

• Języki publikacji: EN

Abstrakty

EN

Spent Pot Lining (SPL) cathode pot, waste from the aluminium smelting process needs detoxification from cyanides, washing out water-soluble salts and extraction of the cryolite (Na₃AlF₆) decomposition products to be recycled. Revealed cryolite decomposition mechanism with NaOH opens possibilities to explore its critical role in the reactive extraction process. Common Na⁺ ion from NaOH hinders the solubility of the product but also drives mass transfer to the reaction site. Reaction mass balance provides adequate liquid to solid ratio (L/S) and NaOH concentration range. A newly developed kinetic model based on Whitman film theory and NaOH mass flow enables prediction of the reaction time to decompose cryolite to a low enough level. Results show that the internal particle resistance to transport (1/k_s) is 19 times larger than the external (1/k_l) one and governs the whole process.

Słowa kluczowe

EN

spent pot lining; NaOH concentration role; cryolite decomposition; reaction mechanism; kinetic model

• Wydawca: West Pomeranian University of Technology. Publishing House
• Czasopismo: Polish Journal of Chemical Technology
• Rocznik: 2021
• Tom: Vol. 23, nr 1
• Strony: 37--44
• Opis fizyczny: Bibliogr. 25 poz., rys., tab., wz.

Twórcy

autor

Tropenauer Blaž

• TALUM d.d. Kidričevo, Tovarniška cesta 10, 2325 Kidričevo, Slovenia

autor

Klinar Dušan

• Scientific Research Centre BISTRA Ptuj Slovenia

autor

Golob Janvit

• University of Ljubljana Faculty of Chemistry and Chemical Technology Ljubljana, Slovenia

Bibliografia

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Uwagi

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2021).