Document Type


Date of Award

Fall 10-31-1994

Degree Name

Master of Science in Environmental Science - (M.S.)


Chemical Engineering, Chemistry and Environmental Science

First Advisor

S. Mitra

Second Advisor

Barbara B. Kebbekus

Third Advisor

Richard B. Trattner


A novel method for continuous monitoring volatile organic compounds (VOCs) in air at trace level is presented. A membrane module and a microtrap were used along with gas chromatographic analysis. The membrane module consisted of a bundle of silicone rubber hollow fibers and separated the VOCs from the gaseous stream. The microtrap which is a very small adsorbent trap played the roles of preconcentrator and injector. The VOCs selectively permeate across the membrane into a strip gas in the membrane module. Before entering the GC column, the VOCs are trapped and concentrated by the microtrap. Desorption of the VOCs is accomplished by direct electric heating. A concentration pulse is generated by fast heating, which act as an injection for GC separation. Continuous monitoring is done by making injections at fixed intervals of time, while the emission stream flows continuously through the membrane module. In this study, the performance of the system was evaluated and the different parameters were studied.