Miller process Miller process The Miller process is an industrial-scale chemical procedure used to refine gold to a high degree of purity (99.95%). It was invented by Francis Bowyer Miller ( patented 1867). This chemical process involves blowing a stream of pure chlorine gas over and through a crucible filled with molten, but impure, gold. This process purifies the gold because nearly all other elements will form chlorides before gold does, and they can then be removed as salts that are insoluble in the molten metal. When all impurities have been removed from the gold (observable by a change in flame color)
Petroleum refining processes Petroleum refining processes Petroleum refining processes are the chemical engineering processes and other facilities used in petroleum refineries (also referred to as oil refineries) to transform crude oil into useful products such as liquefied petroleum gas (LPG), gasoline or petrol, kerosene, jet fuel, diesel oil and fuel oils. Petroleum refineries are very large industrial complexes that involve many different processing units and auxiliary facilities such as utility units and storage tanks. Each refinery has its own unique arrangement and combination of refining processes largely determined by the refinery location, desired products and economic considerations. Some modern petroleum refineries process as