Submillimeter Wave Spectroscopic Sensor for Detection of Carbonyls and Other Gaseous Pollutants

Oral Presentation

Prepared by C. Ball1, F. De Lucia2
1 - Battelle, 505 King Avenue, Columbus, OH, 43201, United States
2 - Ohio State University, Dept. of Physics, 191 W. Woodruff Ave., Columbus, OH, 43210, United States


Contact Information: ballc@battelle.org; 614-424-6502


ABSTRACT

Battelle and The Ohio State University Department of Physics have developed a novel chemical gas sensor technology that is capable of meeting numerous air pollution monitoring needs. Specifically, this technology provides a measure of carbonyls such as formaldehyde, acrolein, acetaldehyde, etc., in near-real time and could be a replacement for sampling and offline analysis by way of U.S. EPA Compendium Method TO-11A. Our sensor implementation embodies a unique combination of high resolution submillimeter wave (SMMW) spectroscopy with gas pre-concentration technologies to enable highly sensitive detection and highly specific identification of gaseous compounds. Under the DARPA Mission Adaptable Chemical Sensor (MACS) program, we developed and tested a laboratory prototype sensor that detects selected gases at parts-per-trillion (ppt) level sensitivity and discriminates components of a mixture of more than 30 gases. This level of performance is achieved within a 10 minute (or less) measurement cycle that includes gas sample acquisition and pre-concentration, spectroscopic interrogation, and data analysis. The current research prototype has a volume of 1 ft3 and is configurable for direct user interface or for completely autonomous operation. In addition to carbonyls, the SMMW sensor can detect, identify, and quantify numerous other pollutants of interest, including NO, NO2, NH3, SO2, CO, and various alcohols. The performance of the prototype sensor will be presented and implications for its use in ambient and indoor air monitoring of various chemicals of interest will be explored.