Recycling a Nonionic Aqueous-Based Metal-Cleaning solution with a Ceramic Membrane: Pilot-Sacae Evaluation

摘要

The effectiveness of a zirconium dioxide (ZrO_2) membrane filter was evaluated for recycling a nonionic aqueous metal cleaning bath under real-world conditions. The pilot-scale study consisted of four 7-to 16-day filtration runs. Each process a portion of the cleaning bath during immersion cleaning of aircraft engine and motor parts. The results indi- cated that the filter was effective in removing contaminants such as oil and grease and suspended solids form the process solution, thus extending the life-span of the bath up to three times. The process bath, however, had to be replenished with surfactant additives to compensate for those removed by the fil- ter. The fouled membrane could be effectively cleaned with its permeability fully restored for reuse.