Pollution Prevention via Recovery of Cerium (IV) Oxide in Optics Company

Elsevier, Case Studies in Chemical and Environmental Engineering, 24 February 2020, 100003
Eugene Park, William Gallagher, Zachary Hobbs, Mark Mayton

Pollution prevention methods were applied at an optics manufacturer in an effort to improve recovery of a valuable polishing component, cerium oxide (ceria), 77% of which was lost to dragout and sewer discharge. Centrifugation and microfiltratiion were evaluated to develop a process that would increase recovery of used ceria, which would then be sent back to the ceria supplier for reclamation and reuse. Full-scale implementation included a high-speed centrifuge that operates continuously with a microfiltration system through recirculation in a single process tank. Sydor Optics has improved ceria recovery from 23% to 48%, saving thousands of dollars annually.