MONITORING AND ANALYZING OF A CHEMICAL-REACTION PROCESS USING REACTION HEAT-INDUCED OPTICAL BEAM DEFLECTION

A reaction heat-induced optical beam deflection method has been applie d for monitoring and analyzing a chemical reaction process. A reaction cell, whose bottom is a thin gold film, is immersed into a CCl4 phase where a probe beam is passed. Reaction heat of the water phase is tra nsferred to the gold film and the CCl4 phase, and thus a temperature g radient is generated in the CCl4 phase. This temperature gradient indu ces deflection of the probe beam. The deflection signal of a slow chem ical reaction is considered as a convolution of the reaction rate and the instrumental response function, which is considered to be proporti onal to the decay curve of deflection signal for a very fast reaction or pulse reaction. The neutralization reaction between H2SO4 and NaOH, and the redox reaction between KMnO4 and Na2C2O4 are employed as a fa st and slow model reaction, respectively. The deflection signals for t he fast and slow reaction systems are monitored and compared. Furtherm ore, time profiles of the redox reaction rates are obtained by deconvo lution treatments of the deflection signal data, and are compared with the results obtained by a transmittance method. The catalytic effect of Mn2+ in the KMnO4-Na2C2O4 redox reaction is examined as well. Impro vements of this method are also discussed.