Trials on zinc electrowinning from sulphate-type electrolytes replenished with waste zinc hydroxide

• Autorzy: Stefanowicz T. , Napieralska-Zagozda S. , Osińska M. , Skotarczyk A.

Warianty tytułu

PL

Próby elektrochemicznego otrzymywania cynku z elektrolitów siarczanowych uzupełnianych odpadowym wodorotlenkiem cynku

• Języki publikacji: EN

Abstrakty

EN

Zinc electrowinning was performed with insoluble graphite anodes at current density of Dk = 5 A/dm2 in 3 sulphate-type electrolytes. During electrolysis the pH value decreased below pH 0.8. To rise pH and to replenish zinc concentration the waste Zn(OH)2 was batched to electrolyte. The zinc layers of approx. 800 mm were deposited with the average efficiency of 90%. Trials evidenced that in case of iron-sheet cathodes due to different hydrogen overvoltage on zinc and on iron, the deposited zinc layer, depending on zinc concentration in electrolytes may be covered on the whole surface with cavities either drop-like convexities. Such abnormal shape of zinc layer did not appear in case of zinc-sheet cathode. During the electrowinning trials in continuous-flow electrolysis cell with zinc cathode the smooth, flat zinc deposit layer was obtained. In spite of low pH, the added zinc hydroxide dissolves slowly and the periodical batching of Zn(OH)2 with continuous filtration of electrolyte was required. After 100 Ah some erosion traces on graphite anodes were noticed.

Słowa kluczowe

EN

zinc hydroxide waste; electrowinning; sulphate-type electrolytes

PL

wodorotlenek cynku odpadowy; elektroliza

• Wydawca: Centrum Materiałów Polimerowych i Węglowych PAN
• Czasopismo: Polish Journal of Applied Chemistry
• Rocznik: 2001
• Tom: Vol. 45, nr 1-2
• Strony: 33--40
• Opis fizyczny: Bibliogr. 9, tabl. 1, rys. 5

Twórcy

autor

Stefanowicz T.

• Institute of Chemistry and Technical Electrochemistry, Poznań University of Technology, Poznań, Poland

autor

Napieralska-Zagozda S.

• Institute of Chemistry and Technical Electrochemistry, Poznań University of Technology, Poznań, Poland

autor

Osińska M.

• Institute of Chemistry and Technical Electrochemistry, Poznań University of Technology, Poznań, Poland

autor

Skotarczyk A.

• Institute of Chemistry and Technical Electrochemistry, Poznań University of Technology, Poznań, Poland

Bibliografia

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