Reagents & Chemicals

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, … Read more

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 … Read more

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 … Read more

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 … Read more

Determine Relative Affinity of Metals for Cyanide Solutions

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 … Read more