chemical engineering The branch of engineering concerned with industrial manufacture of chemical products. It is a discipline in which the principles of mathematical, physical and natural sciences are used to solve problems in applied chemistry. Chemical engineers design, develop, and optimise processes and plants, operate them, manage personnel and capital, and conduct research necessary for new developments. Through their efforts, new petroleum products, plastics, agricultural chemicals, house-hold products, pharmaceuticals, electronic and advanced materials, photographic materials, chemical and biological compounds, various food and other products evolve