Leaching of Pure Chalcocite with Reject Brine and MnO2 from Manganese Nodules

Kinetics of chemical leaching of chalcocite from low-grade copper ore: size-distribution behavior

Kinetics of the chemical leaching of chalcocite from a low-grade copper ore in a ferric sulfate medium was investigated using the constrained least square optimization technique. The experiments were carried out for different particle sizes in both the reactor and column at constant Eh, pH, and temperature. The leaching rate increased with increase in the temperature. About 50% of the Cu recove...

Leaching Recovery of Zinc, Cobalt and Manganese from Zinc Purification Residue

This paper reports on the recovery of zinc, cobalt and manganese by two-step leaching of zinc-plants purification residue with sulfuric acid. The residue, hot filter press cake (HFC), contains 14 % ZnO, 4.8 % Co3O4 and 22.9 % MnO. Effects of different parameters are determined and used to optimize the process. With acid to hot filter press cake (HFC) stoichiometry of 0.85, acid concentration of...

Fungal Leaching of Manganese Ore

Bioleaching is technologically feasible for extraction of manganese from low grade ores (containing manganese less than 35% by weight). The principle involves the non-enzymatic reduction of pyrolusite [Mn(IV) oxides] to +2 oxidation state by fungi with the production of metabolites such as oxalic acid and citric acid. In the present investigation, a fungal strain, Penicillium citrinum was isola...

A Column Bioleaching Model for Chalcocite: An Investigation of Oxygen Limitation and Bacterial Inoculation on Leaching

synthesis of sulfides from alcohols and thiols in solvent-freeconditions and deoxygenation of sulfoxides

کاتالیست یک سنتز جدید برای تیواترها توصیف شده است. واکنش الکل ها با آریل، هتروآریل و آلکیل تیو ل ها درحضور 1،3،5- تری آزو- 2،4،6- تری فسفرین-2،2،4،4،6،6 هگزاکلراید ((tapc به عنوان یک کاتالیست موُثر، بازده های خوب تا عالی از تیواترها را حاصل می کند. علاوه براین، واکنش تحت شرایط بدون فلز و بدون حلال پیش می رود، بنابراین یک مکمل جالب برای روش های شناخته شده سنتز تیواترها ارائه می دهد. یک مکانیسم ا...