Parameter optimization for the measurement of VOCs by canister system

With growing concern for quality of the environment, demand for reliable and sensitive monitoring techniques for organic compounds in the atmosphere has increased recently. Canister sampling and analysis is becoming a widely accepted choice for the measurement of volatile organic compounds (VOCs). Before carrying out any measurement it is necessary to optimize parameters in order to get reproducible results. In view of this, a canister sampling technique was optimized for efficient measurement of various VOCs, including sulfur and chlorinated compounds. For all studied compounds the optimum trap desorption tem­perature was found to be 225°C, while for CCl4 the optimum temperature was lower and this compound shows a decrease in response with the increase in trap desorption temperature. Other chloro compounds like chloroform and 1, 2-dichloroethane showed the same behavior as other organic compounds. Furthermore, cold trap desorption temperature and cryo injection time and moisture control system (MCS) were also optimized.