The Feasibility of Concentrating/Separating Dilute Nitrocellulose Acid Wastewaters by Reverse Osmosis.

摘要

This feasibility study focused on the application of membrane technology for the concentration and/or separation of dilute acid wastewaters. Preliminary laboratory investigations using commercially available cellulose-acetate reverse osmosis (RO) membranes were conducted. The objective of this study was to concentrate the dilute acids as a unit process toward abating the nitrate pollution problem or as an intermediate step in the recovery of the nitric and sulphuric acids. Results of these preliminary investigations indicated that RO was a potential candidate for larger scale application and, therefore, more detailed work was warranted. Of special interest was the development of an acid-resistant membrane to counter the susceptibility of cellulose-acetate to hydrolysis when continuously exposed in an acidic environment. The application of cellulose-acetate and modified sulfonated polyphenylene oxide RO membranes as a unit process in the treatment of dilute acid wastewaters generated at the nitrocellulose manufacturing plant is technically feasible. Acidic corrosion of the metallic components of the RO system can introduce operational problems that will significantly interfere with the rejection and flux rates of the RO membranes.