Thu, 07/05/2007 - 7:50am
Trace Source 57FPK gas-fed permeation tubes are designed to produce stable ppb calibration standards of arsine and other hydride impurities in polymerization grade ethylene and propylene. The tubes are used with a gas standards generating instrument that maintains the tube at constant temperature and flushes the tube with a constant flow of clean olefin matrix gas. A small steady flow of arsine permeates from the tube, mixes with the olefin matrix gas, and creates a flowing calibration standard. Calibration is based on the Standard Additions Principle to compensate for any residual arsine in the clean olefin matrix. Concentrations from below 10 ppb to over 500 ppb can be produced. These permeation tubes use arsine (or other hydride) gas as the arsine source. This technique reduces temperature sensitivity, lowers the quantity of arsine in the tube, and allows the technique to be used for higher pressure gases such as phosphine and silane. Conventional permeation tubes contain liquid analyte.
KIN-TEK Laboratories Inc., La Marque, TX; 409-938-3627; www.kin-tek.com