The specialty chemical maker Lubrizol has hired Rebecca Liebert to serve as its next CEO. Liebert was an executive with the paint and materials firm PPG Industries, where she led its automotive coatings business. She was previously the CEO of the process technology firm Honeywell UOP. This marks Lubrizol’s fourth chief executive in 2 years. Longtime CEO Eric Schnur was replaced by Chris Brown last year after a fire at a Lubrizol plant. In March, Mary Rhinehart stepped in as interim chief while Lubrizol looked for a replacement.