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A Novel Process for Recovery of Key Elements from Commercial Cathode Material of End-of-Life Lithium-Ion Battery

Wang Jei-Pil

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 3

745--750

EN

A novel process to recover lithium and manganese oxides from a cathode material (LiMn2O4) of spent lithium-ion battery was attempted using thermal reaction with hydrogen gas at elevated temperatures. A hydrogen gas as a reducing agent was used with LiMn2O4 powder and it was found that separation of Li2O and MnO was taken place at 1050°C. The powder after thermal process was washed away with distilled water and only lithium was dissolved in the water and manganese oxide powder left behind. It was noted that manganese oxide powder was found to be 98.20 wt.% and the lithium content in the solution was 1,928 ppm, respectively.

2

Thermal reaction of hydrogen and oxygen: a steady-state criterion

Głowiński J., Tylus W., Piotrowski T.

Polish Journal of Chemical Technology

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2003

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Vol. 5, nr 3

57-60

EN

The explosion pressure limits were assessed for a stoichiometric hydrogen-oxygen mixture, using the steady-state criterion constructed for hydrogen atoms. If the concentration of hydrogen atoms reaches the steady-state values, a steady-state reaction is observed. If the steady-state values are not reached, the reaction proceeds with explosive rates. The values of the explosion pressure limits established with the steady-state criterion are compared with the experimental values and with the values calculated from the condition of equality of chain-branching and chain-breaking rates.

3

Investigation of structural chemistry of thermal processes applied for improvement of grindability of ulexite.

Sener S., Ozbayoglu G.

Physicochemical Problems of Mineral Processing

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2000

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Vol. 34

25-33

EN

In this investigation, mechanism of the thermal processes and effect of the mineralogical and structural modifications on the grindability of ulexite were investigated. The mechanism of the thermal reactions were examined by thermo-anal. methods including TGA and DTA. The mineralogical and structural modifications were investigated by XRD and SEM techniques, respectively. The results indicated that ulexite thermally decomposes within 60-500°C. The structure was first transformed into NaCaB5O6(OH)6.3H2O and then NaCaB5O decomposes 6(OH)6.H2O and finally became as completely X-ray amorphous phase accompanied with the thermal processes in the sequence of two-stage dehydration and two-stage dehydroxylation reactions resulting in two endothermic DTA peaks at 151°C and 180°C. Further treatment caused two-stage recrystallization. processes resulting in an exothermic DTA peak at 636°C and an endothermic peak at 855°C. The changes in the grindability of ulexite were determined. in terms of work index by the Hardgrove Grindability Test. The results showed that work index of ulexite was found as 7.11kWh/shton and decreased to 3.5 kWh/shton level within 200-280°C for 60 min. Further heating lead to 8.49 kWh/shton at 640°C for 60 minutes.

PL

W pracy badano mechanizmy procesów termicznych i wpływ przemian mineralogicznych i strukturalnych na rozdrobialność ulexytu. Badania mechnanizmów reakcji prowadzono metodą analizy termicznej w tym TGA i DTA, a zmiany mineralogiczne i struktutralne.za pomocą technik XRD i SEM. Wyniki wskazują, że ulexyt ulega termicznemu rozkładowi w zakresie 60-500 st.C. Najpierw powstaje NaCaB5O6(OH)6*3H2O a potem NaCaB3O6(OH)6*H2O) ostatecznie stając się amorficzny. Towarzyszą temu procesy termiczne, kolejno, dwustopniowe odwodnienie i dwustopniowa dehydroksylacja powodując dwa endotermiczne piki na krzywej DTA przy 151 st. C i 180 st.C. Dalsze ogrzewanie powoduje dwustopniową rekrystalizację powodując egzotermiczny pik przy 636 st. C. oraz endotermiczny pik przy 855 st. C. Zmiany rozdrabialności ulexytu określono za pomocą test rozdrabialności Hardgrove'a. Stwierdzono, ze indeks rozdrabialnosci ulexytu wynosi 7,11 KWh/krotka tonę i maleje do 3,5 KWH/krótką tonę dla probek wygrzewanych w zakresie 200-280 st. C. Przez 60 minut. Dalsze ogrzewanie w temp. 640 st.C przez 60 minut podnosi wartość indeksu do wartości 8,49 KWh/krótką tonę.