Recovery of manganese from ores was investigated by reductive leaching method using reeds as a reductant in the sulfuric acid medium. Cellulose, hemicellulose, and lignin are natural reducing agents which widely used to recover manganese. Effects calcination temperature holding time on efficiency impurities were examined. The have significant effect extraction experimental results demonstrated ...

Hausmannite is a common low-valence manganese oxide mineral with distorted spinel structure in surficial sediments. Although natural Mn oxides often contain various transition metal (TM) impurities, few studies have addressed the substitution mechanisms of TMs, such as cobalt (Co), hausmannite and induced changes physicochemical properties. In this study, Co-doped hausmannites final Co/Mn molar...

Abstract A set of the four manganese oxide powders α-MnO 2 (hollandite), δ-MnO (birnessite), Mn O 3 (bixbyite), and 4 (hausmannite) have been synthesized in a phase-pure form tested as catalysts three different oxygen evolution reactions (OER): electrochemical OER KOH (1 mol L −1 ), chemical using aqueous cerium ammonium nitrate, H decomposition. The trends (hollandite >> bixbyite > bi...

Analyses of archaeological materials aim to rediscover the know-how of Prehistoric people by determining the nature of the painting matter, its preparation mode, and the geographic origin of its raw materials. This study deals with identification of manganese oxides in black pigments by micro-XANES (X-ray absorption near-edge structure) based on previous TEM (transmission electron microscopy) s...