INHIBITION EFFECT IN SUPERCRITICAL WATER OXIDATION OF HYDROQUINONE

In the oxidation reactions of hydroquinone under a supercritical condi tion (temperature of 683 K and pressure of 24.5 MPa), the conversion w as found to become saturated despite the very fast initial reaction. T his behavior was quite different from that under a subcritical conditi on (temperature of 633 K and pressure of 24.5 MPa). Under both conditi ons, p-benzoquinone was found to be an important intermediate. The yie ld of CO2 was very small, which indicates a strong inhibition effect o f hydroquinone and/or its derivatives. These inhibition phenomena shou ld be taken into account very carefully in the application of supercri tical water oxidation for treating waste organic materials where a com plete decomposition is very important.