Izdvajanje kobalta iz primarnih i sekundarnih materijala - pregled

Srećko Stopić,Bernd Friedrich

doi:10.5937/vojtehg68-26117

Abstract

Introduction/purpose: Cobalt is a strategic metal for industrial application. Cobalt recovery from oxidic ores such as laterite and sulphidic ores, and from secondary materials during acidic treatment and precipitation is a highly used strategy ensuring different products such as cobalt hydroxide, cobalt oxide, and finally metallic cobalt. Methods: Familiarity with cobalt behavior in hydrometallurgical processes such as dissolution at atmospheric and high pressure, precipitation, neutralization, filtration and hydrogen reduction is most important for cobalt recovery from ores and secondary materials. Pyrometallurgical methods such as roasting and flash smelting are applied for the treatment of sulphidic ores combined with solvent extraction and electrolysis in order to obtain cathodic cobalt. Results: Powders of nickel-cobalt hydroxide were obtained from ores using sulphuric acid under high pressure in an autoclave and after precipitation with MgO. Solvent extraction was used to separate cobalt from nickel. The final step of cobalt recovery from a solution is using electrolysis. Cobalt and cobalt compounds such as cobalt carbonate and cobalt hydroxide can be obtained from secondary materials in hydrometallurgical operations. Conclusion: Hydrometallurgical and pyrometallurgical processes are mostly applied for cobalt recovery from primary ores (oxidic and sulphidic compounds) and from secondary materials (cemented tungsten carbide, polycrystalline diamond blanks, and waste cathodic materials from lithiumion batteries).

Highlights

Cobalt, an element with atomic number 27, is a ferromagnetic transition metal located between iron and nickel in the periodic table of elements
The main purpose of this study is to present some processes and results regarding cobalt recovery from primary materials and secondary materials such as WC-Co, lithium-ion batteries and polycrystalline diamond blanks
This study was performed at between 60°C and 80°C aiming at optimizing the process of leaching cobalt and cobalt compounds from polycrystalline diamond blanks using the mixing of nitric and hydrochloric acid in a conventional leaching method augmented with ultrasound

Summary

Introduction

An element with atomic number 27, is a ferromagnetic transition metal located between iron and nickel in the periodic table of elements. Because of its application in lithium-ion batteries, cemented carbides and catalysts, and high demands in future, cobalt belongs to critical metals. The companies, such as Umicore (Belgium), Xstrata Nickel (Canada), Accurec (Germany), Inmetco (USA), S.N.A.M (France) and Sony-Sumitomo (Japan) use the pyrometallurgical strategy as the main recycling process to recycle rechargeable portable and industrial Li–ion batteries including NiMH and NiCd batteries Valuable metals, such as Co and Ni, are fully recovered in the form of alloy at high temperature in contrast to Al, Li and Cd, which stay in slag or flue dust (Wang & Friedrich, 2015, pp.178). The main purpose of this study is to present some processes and results regarding cobalt recovery from primary materials (lateritic and sulphidic ores) and secondary materials such as WC-Co, lithium-ion batteries and polycrystalline diamond blanks

Thermochemistry of cobalt dissolution in acidic medium

Recovery of cobalt from complex sulfidic concentrates

Findings

Conclusion