The chemical industry comprises the companies that produce industrial chemicals. Central to the modern world economy, it converts raw materials (oil, natural gas, air, water, metals, and minerals) into more than 70,000 different products. As accepted by chemical engineers, the chemical industry involves the use of chemical processes such as chemical reactions and refining methods to produce a wide variety of solid, liquid, and gaseous materials. Most of these products are used in manufacture of other items, although a smaller number are used directly by consumers. Solvents, pesticides, lye, washing soda, and portland cement are a few examples of product used by consumers. The industry includes manufacturers of inorganic and organic-industrial chemicals, ceramic products, petrochemicals, agrochemicals, polymers and rubber (elastomers), oleochemicals (oils, fats, and waxes), explosives, fragrances and flavours. The process of extracting metals from their ores is called metallurgy. Ores as mined are hardly in a condition to be used directly for the extraction of metals. The ores are generally associated with non-metallic impurities of earth and rocks called gangue or matrix. The book provides the students current information on the different areas of this subject. The publication is useful not only to the students but also to the research scholars and academic professionals.