Dissolution of Mixed Zinc‐Carbon and Alkaline Battery Powders in Sulphuric Acid Using Ascorbic/Oxalic Acid as a Reductant

Recovery of Manganese from Spent Batteries Using Guar Meal as a Reducing Agent in a Sulfuric Acid Medium

“…Total dissolution of zinc and manganese oxides can be achieved by acidic reductive leaching using different acids and reductants. , A manganese sulfate and zinc sulfate solution is obtained, together with other dissolved metals. The aqueous solution is sent to a precipitation step where manganese is precipitated by sodium or potassium hydroxide at pH 10 as a form of manganese hydroxide . Table compares the previous and present study results.…”

“…The aqueous solution is sent to a precipitation step where manganese is precipitated by sodium or potassium hydroxide at pH 10 as a form of manganese hydroxide. 24 Table 6 compares the previous and present study results. Under the tested experimental conditions, the highest manganese recovery was achieved using guar meal.…”

“…A mineralogical study of the mixed zinc–carbon and alkaline battery powder identified hausmannite as the primary manganese mineral in the powder. In addition, waste battery powder contains other manganese oxides, such as Mn 3 O 4 , Mn 2 O 3 , and MnO. ,− The dissolution of manganese dioxides requires a highly acidic medium to completely recover manganese, which results in consumption of the H + ions. Therefore, an initial sulfuric acid concentration of 2 mol L –1 was chosen for the subsequent reductive leaching experiments.…”

“…Recently, much effort has been made to develop a commercial hydrometallurgical process to recover low-grade manganese ores and wastes by using a reducing agent in an acidic medium, such as roasting followed by reductive acid leaching, pyrite reductive leaching, iron­(II) sulfate reductive leaching, aqueous sulfur dioxide reductive leaching, , mixed methanol–sulfuric acid solution reductive leaching, phenol reductive leaching, lactose reductive leaching, , sucrose reductive leaching, , glucose reductive leaching, − sawdust reductive leaching, , corncob reductive leaching, oxalic acid reductive leaching, , citric acid and ascorbic acid reductive leaching, , waste newspaper reductive leaching, hydrogen peroxide reductive leaching, , cane molasses reductive leaching, biogas residual reductive leaching, and activated carbon powder reductive leaching …”