Separation Science and Technology, Vol.39, No.14, 3301-3315, 2004
Phenol hydroxylation with TS-1 in a chromatographic reactor
Phenol hydroxylation with TS-1 was studied in a chromatographic reactor. TS-1 not only acts as the catalyst for the reaction but also the adsorbent for the separation. The reaction/separat ion was carried out at 60degreesC with water and 0.2 wt% of aqueous H2O2 as the desorbent. Separation of hydroquinone (HQ) can be achieved in all cases. With water as the desorbent, separation of catechol (CT) depends on the phenol feed concentration, which has been confirmed from both reaction/separation in the chromatographic reactor and equilibrium competitive adsorption experiment. Some unknown by-products not commonly reported in batch experiments have been observed here. TS-1 can also be regenerated using just water. With the aqueous mixture of H2O2 as the desorbent, separation of HQ and CT is possible. Reactive separation schemes based on the simulated countercurrent technology have been proposed according to the experimental results.
Keywords:phenol hydroxylation;TS-1;chromatographic reactor;reactive separation;hydroquinone;benzoquinone