WET OXIDATION OF NITROTOLUENESULFONIC ACID - SOME INTERMEDIATES, REACTION PATHWAYS, AND BY-PRODUCT TOXICITY

Wet air oxidation (WAO) is effective in the oxidation of 5-nitro-o-toluenesulfonic acid (NTSA); the WAO reaction is first-order with respect to NTSA. Sulfur initially present is almost stoichiometrically converted to sulfate. A significant amount of nitrogen gas and ammonium are present in the reactor offgas and WAO effluent, respectively. No NO(x) or SO(x) is detected. Proposed reaction pathways are presented for the WAO of NTSA, based on the intermediates and end products identified. NTSA concentration up to 150 mg/L does not show inhibitory effects on enriched Nitrosomonas. However, WAO-treated NTSA does show some adverse effect on the nitrite production capability of the Nitrosomonas, thus indicating that some byproducts formed during WAO of NTSA may be more toxic than NTSA itself.