Advanced Development of Immobilized Enzyme Reactors

Removal of low-molecular weight, polar, non-ionic contaminants such as urea and alcohols from aqueous solution is being accomplished using immobilized enzyme technology. Immobilized urease is used to catalyze urea hydrolysis for subsequent removal as ammonia. An alcohol oxidase enzyme-based catalyst is used to catalyze oxidation of alcohols, aldehydes, and similar compounds to organic acids, which are removed by ion exchange.

Fixed bed reactors were successfully developed and delivered to NASA-MSFC for a segment of the Phase III Core Module Integrated Facility (CMIF) Water Recovery Test. Wastewater generated in the End-use Equipment Facility (EEF) was purified using a combination of Multifiltration Unibeds and Enzyme Unibeds. The enzyme beds effectively removed the targeted organics to levels below detection limits (<100-400 ppb). Also, based on the amount of TOC removed, the enzyme beds removed unidentified organic contaminants beyond those specifically targeted. Average effluent TOC concentrations were 1 mg/L.