Second-generation International Space Station Total Organic Carbon Analyzer Verification Testing and On-orbit Performance Results

摘要

The International Space Station (ISS) total organic carbon analyzer (TOCA) is designed to autonomously assess recovered water quality by providing an indication of total organic carbon (TOC). The current TOCA has been on the ISS since November 2008. Functional checkout and operations revealed complex operating considerations. Specifically, failure of the hydrogen (H_2) catalyst resulted in development of an innovative oxidation analysis method that reduces activation time and limits the H_2 produced during analysis, while retaining the ability to indicate TOC concentrations within 25% accuracy. Subsequent testing and comparison to archived samples returned from station and tested on the ground yield high confidence in this method, and in the quality of the recovered water.