Grantee Research Project Results
Final Report: Wireless Electrochemical ClO2 Monitor for Decontamination Operations
EPA Contract Number: EPD08060Title: Wireless Electrochemical ClO2 Monitor for Decontamination Operations
Investigators: Weber, Andrew
Small Business: Giner Inc.
EPA Contact: Richards, April
Phase: II
Project Period: May 1, 2008 through April 30, 2010
Project Amount: $224,997
RFA: Small Business Innovation Research (SBIR) - Phase II (2008) Recipients Lists
Research Category: Small Business Innovation Research (SBIR) , SBIR - Homeland Security
Description:
The U.S. Environmental Protection Agency (EPA) has identified the need for portable, accurate, and field-rugged chlorine dioxide (ClO2) monitors for use in monitoring building decontamination operations. To address EPA’s concern and need, this Small Business Innovation Research (SBIR) Phase II project continued the developmental work started in Phase I to design, develop, and demonstrate a simple-to-operate and advanced novel electrochemical ClO2 microsensor (sensor cell with integrated potentiostatic control and signal-processing circuit) and demonstrate its successful operation with wireless data transmission. The proposed microsensor will be rapid (less than 30 seconds for 90% of full response, T90), accurate, selective, and capable of measuring 0 to 3000 ppm ClO2 in real time with a detection limit of 2 ppb. The unique and advanced sensing technology is based on integrated solid-polymer, proton-conducting electrolytes and thick-film electrode (sputtered or screen printed on alumina substrates) technology. The proposed microsensor will be configured for continuous unattended or handheld operation and it will be fully integrated with wireless data transmission and configured into a compact and lightweight monitor.Summary/Accomplishments (Outputs/Outcomes):
Complete prototype microsensors, comprised of solid-polymer electrolyte membrane pressed against screen-printed, thick-film sensing, counter and reference electrodes and associated components (liquid reservoir and gas access ports), were designed, developed, and fabricated. The sensor cell module was integrated with the electronics module comprised of a mini (1.25″ x 1.25″ x 0.50″) potentiostat printed-circuit board and wireless data-processing and control circuits, designed and developed by Giner, Inc. (Giner), and the performance of the microsensor was evaluated for detection of 0-3000 ppm chlorine dioxide in air mixtures.
Conclusions:
- A small (1.1″ x 1.1″) solid-polymer, electrolyte-based screen-printed three-electrode alumina substrate sensing element for the detection of ClO2 in air mixtures.
- A miniature (1.25″ x 1.25″ x 0.25″) mini-potentiostat to control the potential of the sensing electrode relative to a Pt/air (Pt/air reference electrode potential is approximately 1.0 volt vs. the Normal Hydrogen Electrode) reference electrode. Response current, proportional to the ClO2 concentration flows from sensing electrode to counter electrode.
- Configuring, in a small (2.0″ x 2.0″ x 2.5″) package, the sensor cell module comprised of the solid-polymer, electrolyte-based screen-printed, thick-film electrode substrate and its associated components (liquid reservoir and gas access ports) and the electronics module comprised of the miniature (1.25″ x 1.25″ x 0.25″) low-power and low-noise potentiostat, the sensor control circuitry and a transfer board to accept the wireless data transfer device (Crossbow, micro-RF device) for wireless transmission of sensor data to a central location, such as a personal computer or a laptop.
- Detection of ClO2 in the range of 0 to 3000 ppm with a detection limit of 2 ppb.
- Microsensor operation and ClO2 detection with no interference from chemical compounds, such as ethylene (10 ppm), carbon monoxide (50 ppm), carbon dioxide (100 ppm), Clorox®[1] (5000 ppm), Windex®[2] (1000 ppm) and nitrogen dioxide (6 ppm).
- Microsensor operation and ClO2 detection in the temperature and relative humidity (R.H.) range of +1°C to +40°C and 5% to 95% R.H., respectively, with minimal effect on the performance of the sensor.
- Successful operation of the prototype microsensor with wireless data transmission.
[1] Clorox® is a registered trademark of The Clorox Company
Supplemental Keywords:
Sustainable Industry/Business, Scientific Discipline, RFA, Technology for Sustainable Environment, Sustainable Environment, Environmental Engineering, Environmental Monitoring, bioterrorism, chlorine dioxide monitoring, micro sensors, decontamination, RFA, Scientific Discipline, Sustainable Industry/Business, Sustainable Environment, Technology for Sustainable Environment, Environmental Monitoring, Environmental Engineering, homeland security, decontamination, micro sensors, chlorine dioxide monitoringSBIR Phase I:
Wireless Electrochemical ClO2 Monitor for Decontamination Operations | Final ReportThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.