Abstract: A process for continuous adiabatic nitration of toluene to mononitrotoluene (MNT). The process yields a product quality of MNT that is comparable to that obtained by isothermal production. The process uses excess toluene, with the reaction rate being controlled to maintain a residual of 0.003-0.102 wt % nitric acid in the spent acid and an orange to red color of the spent acid. Further process conditions include re-concentrated sulfuric acid at 83 to 99 degrees C. with a concentration of sulfuric acid from 66 to 70.5 wt %. This is mixed with nitric acid to generate a mixed acid with 1.0 to 3.8 wt % nitric acid and toluene is added at a rate of 1.1 to 1.71 moles toluene/mole nitric acid. The reactants are mixed in a reactor with an overall average mixing intensity of 5.8 to 19 W/kg of contained solution.

Abstract: A process for treating wastewater containing nitro-hydroxy-aromatic compounds using oxidative sub-critical conditions. The wastewater to be treated is adjusted to contain excess hydroxide equivalent to greater than three moles of free hydroxide per mole of total nitro-hydroxy-aromatic compounds, and a sub-stoichiometric amount of an oxidant is supplied to the wastewater. The nitro-hydroxy-aromatic compounds may include nitro-phenol salts or nitro-cresol salts.

Abstract: A process for continuous adiabatic nitration of toluene to mononitrotoluene (MNT). The process yields a product quality of MNT that is comparable to that obtained by isothermal production. The process uses excess toluene, with the reaction rate being controlled to maintain a residual of 0.003-0.102 wt % nitric acid in the spent acid and an orange to red color of the spent acid. Further process conditions include re-concentrated sulfuric acid at 83 to 99 degrees C. with a concentration of sulfuric acid from 66 to 70.5 wt %. This is mixed with nitric acid to generate a mixed acid with 1.0 to 3.8 wt % nitric acid and toluene is added at a rate of 1.1 to 1.71 moles toluene/mole nitric acid. The reactants are mixed in a reactor with an overall average mixing intensity of 5.8 to 19 W/kg of contained solution.

Abstract: A process for treating wastewater containing nitro-hydroxy-aromatic compounds using oxidative sub-critical conditions. The wastewater to be treated is adjusted to contain excess hydroxide equivalent to greater than three moles of free hydroxide per mole of total nitro-hydroxy-aromatic compounds, and a sub-stoichiometric amount of an oxidant is supplied to the wastewater. The nitro-hydroxy-aromatic compounds may include nitro-phenol salts or nitro-cresol salts.

Abstract: An electrochemical cell design is disclosed for the particular application of the electrochemical treatment of contaminants in water. The cell is designed to allow the treatment of low concentrations of contaminants in low conductivity water efficiently, and to be simple to fabricate. The design incorporates tapered inlet and outlet fluid flow manifolds so that the cell pressure drop will be almost entirely due to fluid contacting the electrodes, thus maximising the effective use of the system pump power. A short anode to cathode distance and thin working electrodes are used to minimise resistive electrical power losses. The parallel slacked arrangement of the electrodes and the smooth inlet and outlet designs leads to relatively even distributions of current density and mass transfer resulting in maximal utilisation of the entire active electrode surface area.

Abstract: The invention disclosed relates to an electrochemical process for decreasing high levels of organic contaminants in metal plating baths. The process involves breaking down the organic contaminants in an electrochemical cell by electrochemical oxidation. The electrochemical cell includes an anode comprising an active material which is stable at low (acid) pH and at the high electrical potential required to break down the organic contaminants by oxidation. Typical examples of such anodes include a valve metal substrate coated with doped tin dioxide, lead dioxide, or platinum-based materials, the latter in some instances being coated on a high surface area valve metal substrate.

Abstract: An electrochemical cell design is disclosed for the particular application of the electrochemical treatment of contaminants in water. The cell is designed to allow the treatment of low concentrations of contaminants in low conductivity water efficiently, and to be simple to fabricate. The design incorporates tapered inlet and outlet fluid flow manifolds so that the cell pressure drop will be almost entirely due to fluid contacting the electrodes, thus maximising the effective use of the system pump power. A short anode to cathode distance and thin working electrodes are used to minimise resistive electrical power losses. The parallel slacked arrangement of the electrodes and the smooth inlet and outlet designs leads to relatively even distributions of current density and mass transfer resulting in maximal utilisation of the entire active electrode surface area.

Abstract: The invention disclosed relates to an electrochemical process for decreasing high levels of organic contaminants in metal plating baths. The process involves breaking down the organic contaminants in an electrochemical cell by electrochemical oxidation. The electrochemical cell includes an anode comprising an active material which is stable at low (acid) pH and at the high electrical potential required to break down the organic contaminants by oxidation. Typical examples of such anodes include a valve metal substrate coated with doped tin dioxide, lead dioxide, or platinum-based materials, the latter in some instances being coated on a high surface area valve metal substrate.

Abstract: A process is described for electrochemically "collecting" certain organic compounds from aqueous solutions in an immobilized and concentrated manner conducive to subsequent destruction. The method is applicable for organic compounds amenable to electrochemical coupling, e.g. by condensation. The method involves the electrochemical reaction of the organic compounds to form substantially water insoluble coupling products in the form of deposits or films on the working electrode surface. This method has the advantage of greatly concentrating and immobilizing the organic compounds on the surface of the working electrode. The immobilization of the organics allows the material to be transferred to a different environment or allows the environment to be changed to facilitate destruction of the organics.