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The development of a new microfluidics based carbon analyzer that is capable of generating chemicals needed in the analysis is described. The analyzer design is based on several components, an electrochemical cell, a membrane conductivity sensor, and an electrochemical water de-ionizer, which utilize porous membranes such as proton exchange membrane, gas separation membrane, and ion exchange membrane n their operation. These membrane-based microfluidic devices (MBMD) allow miniaturization of the carbon analyzer into a compact instrument which will provide high sensitivity and low power consumption. Each of the membrane-based microfluidic components was fabricated and their functioning tested over a broad range of inorganic or organic carbon content in water samples.

Currently used instruments for the analysis of total inorganic carbon (TIC) and total organic carbon (TOC) in water and wastewater samples require the use of hazardous chemicals which is not acceptable in their application for long-term space missions. A new design concept of the “reagentless” carbon analyzer (RCA) for determination of both TIC and TOC for water quality monitoring in space is proposed and tested. The concept is based on generating all the chemicals needed for the TIC and TOC analysis within the instrument, and avoiding the need for storing a supply of chemicals. The chemicals are either generated or recirculated in the instrument, or an alternative approach for their use is developed, such as using photocatalytic oxidation instead of oxidizing chemicals for TOC analysis. The fully developed miniaturized instrument will incorporate microfluidic based design principles.