Jacobs Engineering Group Inc. named Steven Demetriou, former chief executive of aluminum producer Aleris Corp., as its chief executive and president, on Monday. Demetriou, who also takes a seat on the Pasadena engineering firm’s board, will assume the roles Aug. 17. He replaces Craig Martin, who retired in December for health reasons after serving as chief executive since 2006. Board Chairman Noel Watson served as executive chairman while the company searched for a new chief executive. A 30-year veteran in metals, specialty chemicals, oil and gas, manufacturing and fertilizers, Demetriou also spent 16 years at ExxonMobil in U.S. and European operations, according to Jacobs. Linda Fayne Levinson, independent director and chair of Jacobs’ human resource and compensation committee, said Demetriou was chosen for his performance-driven leadership, ability to inspire a positive corporate culture and comfort working with clients and employees around the world.