SX Solvent Extraction Process Principles Theory
An increasing demand for metals in general, and higher purity metals in particular, decreasing ore grades and more stringent environmental regulations have driven, and will continue to drive, research into finding more effective and efficient methods for processing the ores available to us, and recycling previously used metals. Hydrometallurgy has provided, and will continue to […]
Solvent Extraction Plants: Thiele Diagram & Theoretical Design Aspects
It has been explained in an earlier talk that solvent extraction in the copper industry is used to convert impure, and frequently very dilute copper solutions into very pure and concentrated solutions from which pure copper can be extracted by a variety of means, usually electrochemical. These impure solutions emanate from in-situ leaching, dump leaching, […]
Solvent Extraction Process SX: Hydrometallurgical Extraction of Copper
In recent years, the principle and theory behind solvent extraction has gained wide acceptance as one of the new tools of modern hydro-metallurgy. With the growing demand for metals of ever higher purity, the increasing use of unusual metals, and the necessity for treating ores of lower grade and greater complexity, solvent extraction has joined the […]
Relation Between the Strength of Cyanide Solutions and Their Dissolving Power
It has already been shown by Maclaurin, that the dissolving power of a cyanide solution saturated with oxygen increases with its strength until a strength of 5 or 10 per cent, is reached, and diminishes again as the strength in cyanide increases beyond that point. But, so far as I am aware, no one has […]
Hydrogen Peroxide & Gold Cyanidation
The peroxide of hydrogen used was Marchand’s medicinal, containing 3.3 per cent, of available peroxide, as determined by titration with permanganate of potassium. According to the new theory, the H2O2, (±) takes up from the gold strip o, which becomes positive, two units of negative electricity and dissociates into 2 (OH) (—). In the first […]
Metal’s Electrochemistry of Cyanide Solutions
The practice of the cyanide-process of gold-extraction has brought to light many important contradictions of familiar chemical analogies, which still obscure both the theory and the practice of the art with distinctions subtler and more difficult to make or follow than those which delighted the heart of the old-time metaphysician. Yet Nature herself has drawn […]
Relative Affinity of Metals for Cyanide
In looking about for some means of determining the relative affinities of the metals for cyanide solutions, I long ago came to the conclusion that the determination of the relative electromotive forces of the metals in solutions of different strengths was the simplest, readiest, and most certain that could be selected. For, properly considered, it […]