A new sampling system has been designed and interfaced with high-speed gas chromatography (HSGC) to monitor and assess the performance of a trickle-bed bioreactor designed for the removal of volatile organic compounds from air. A portion of a gas stream containing styrene and toluene was sampled both before and after passing through the bioreactor by means of a dual-loop sampling system. With a frequency of as high as 2 per minute, treated and untreated samples were alternately transferred on-line to the cryofocusing injection system of a HSGC and analyzed. This analytical system generated data with less than 2 relative standard deviations for standard samples, and residual contamination of subsequent analyses from a highly concentrated sample (2000μg/L) was not observed. A bench-scale bioreactor with a fiber mat support was used in these studies, resulting in residence times for analytes in the bioreactor of as little as 1 5. Rapid monitoring of this system detected subtle changes in the concentration of analytes with 30 s temporal resolution. Measurements showed a statistically significant increase in the removal of styrene from 22 to 27 when water was sprayed over the immobilized bacteria for 30 mm. Overall, the bioreactor removed styrene from the air stream with a specific elimination capacity of 1700 g of styrene (m{sup}3 of biocatalyst){sup}(-1) h{sup}(-1) at a space velocity of 3400 h{sup}(-1).
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