IN-SITU FIBEROPTIC RAMAN-SPECTROSCOPY OF ORGANIC-CHEMISTRY IN A SUPERCRITICAL WATER-REACTOR

In situ measurements were made of several organic chemical reactions i n supercritical water using fiber-optic probes, near-infrared excitati on and CCD array detection. The reactions studied include the conversi on of cyclohexene to cyclohexane and benzene in the presence of a plat inum catalyst, conversion of cyclohexanol to cyclohexene in the presen ce of a cobalt catalyst and the homopolymerization of styrene. Transit ion to the supercritical state was marked by a sudden decrease in the background and the appearance of intense Raman bands for dissolved org anic compounds. The results indicate that this method of study is both sensitive and rapid enough to permit kinetic measurements, even when reactions are completed in less than 2 min.