POLYMER-COATED SURFACE-ACOUSTIC-WAVE MONITORING OF CCL4 IN A STEAM REFORMING REACTOR

A surface acoustic wave (SAW)-based sensor system has been developed, which will sense organic vapors in harsh chemical and physical environments (HCl and steam) by absorbing vapors into a polyisobutylene (PIB) film. The sensor system has been demonstrated on a small-scale steam reforming system during decomposition testing of CCl4, and has st detection limit on the order of 300 ppm, while displaying no visible degradation due to the HCl. The sensor response has been compared to the experimental isotherm developed by Brunauer, Emmett, and Teller (BET) for CCl4 in an atmosphere of CO2 and steam, and the binding energy of the first monolayer of CCl4 onto the film is found to be on the order of 9.6 kcal mol(-1). The sensor system has been tested during industrial-scale waste decomposition in the Synthetica Moving Bed Evaporator (MBEv, Synthetica Technologies, Richmond, CA), and has verified that the MBEv equipment can decompose on the order of 90% of an input CCl4 stream upon vaporization at 300 degrees C.