Miller process the gold is removed and processed in the manner required for sale or use. The resulting gold is 99.95% pure, but of lower purity than gold produced by the other common refining method, the Wohlwill process, which produces gold to 99.999% purity. The Wohlwill process is commonly used for producing high-purity gold, such as in electronics work and the manufacture of some silicates, where exacting standards of purity are required. When highest purity gold is not required, refiners often utilize the Miller process due to its relative ease, quicker turnaround times, and because it does not tie up the large
Industrial separation processes which restricts the movement of one compound but not of the other one (semipermeable membranes) is less common; external fields are used just in special applications. Industrial separation processes Industrial separation processes are technical procedures which are used in industry to separate a product from impurities or other products. The original mixture may either be a natural resource (like ore, oil or sugar cane) or the product of a chemical reaction (like a drug or an organic solvent). Separation processes are of great economic importance as they are accounting for 40 – 90% of capital and operating costs in industry.