A garment to protect the wearer from toxic agents may be made of a fabric that contains an adsorbent, such as activated carbon. In a test of such a fabric, a gas stream containing 7.76 mg/L of carbon tetrachloride (CCl4) was passed through a 7.71-g sample of the fabric at a rate of 1.0 L/min, and the concentration ofCCl4in the gas leaving the fabric was monitored. The run was continued for 15.5 min with noCCl4being detected, after which theCCl4concentration began to rise.
(a) How much CCl4 was fed to the system during the first 15.5 min of the run? How much was adsorbed? Using this information as a guide, sketch the expected concentration of CCl4 in the exit gas as a function of time, showing the curve from t=0 to t»15.5 min.
(b) Assuming a linear relationship between amount of CCl4 adsorbed and mass of fabric, what fabric mass would be required if the feed concentration is 5 mg/L, the feed rate 1.4 L/min, and it is desired that no CCl4 leave the fabric earlier than 30 min?