Industrie De Nora S.p.a.

De Nora Permelec S.p.a.

De Nora Elettrodi S.p.a

Oronzio Denora Impianti Elettrochimici S.p.a.

De Nora S.p.a.

De Nora Electrodi S.p.a.

Giovanni Meneghini

Raffaello Bertin

Carlo Traini

Giuseppe Bianchi

Oronzio De Nora

Giuseppe Faita

Luciano Iacopetti

Corrado Mojana

Felix Prado

Gaetano Porcino

Décio Barros

Takashi Oishi

The invention relates to a process of abatement of the organic content of a depleted brine coming from epoxy compound production involving a vapour stripping step and a mineralisation with hypochlorite in two steps, at distinct pH and temperature conditions.

Method and apparatus for treatment of effluents from production plants of epoxy compounds

The invention relates to a cathode for electrolytic processes provided with a catalytic coating based on ruthenium crystallites with highly controlled size falling in a range of 1-10 nm. The coating can be produced by physical vapor deposition of a ruthenium or ruthenium oxide layer.

Diaphragm of predefined porosity and method of manufacturing

The invention relates to a synthetic diaphragm for chlor-alkali cells with improved energy consumption and gas separation characteristics. The diaphragm comprises a network of polymer fibers bound to a hydrophilic ceramic material containing zirconium chemically bound to hydroxyl groups. The ceramic material is obtained starting from ZrOby a process of hydration under vacuum which can be carried out directly in the cell by means of suitable equipment.

Separator for chlor-alkali electrolytic cells and method for its manufacturing

The invention relates to a device for breaking the electrical continuity of the stream of caustic soda produced in mercury-cathode chlor-alkali plants. The device is comprised of a vessel internally subdivided into three compartments by two flow-conveying septa, the three compartments being in communication and defining a caustic soda tortuous flow-path allowing the centrifugal deposition of mercury microdroplets released by the upstream amalgam decomposer.

Device for the separation of mercury from caustic soda in chlor-alkali plants

There is disclosed an inlet and outlet end-box design for mercury cathode chlor-alkali electrolysis cells of extended lifetime, comprising a composite mechanical structure consisting of a carbon steel bottom entirely supporting the mechanical solicitations, a plastic cover, and a hydraulic head device for washing the mercury and the amalgam. The device is partially extractable thereby allowing the withdrawal of foreign materials accumulated during operation with no need for opening the end-boxes.

End-box for mercury cathode alkali chloride electrolysis cell

The invention relates to an amalgam decomposer for mercury cathode chlor-alkali cells. The amalgam decomposer of the invention contains a filling of carbon steel rings whose external surface is provided with a catalytic coating for amalgam decomposition consisting of one or more electrically conductive metals carbides. The internal surface of the rings is free of catalytic coating and wettable by the amalgam, while the external carbide catalytic coating is not wettable by the amalgam thereby favoring hydrogen evolution.

Amalgam decomposer for mercury cathode cells for alkali chloride electrolysis

The invention describes an improved anode suitable for being installed in chlor-alkali electrolysis cells intercalated to cathode elements provided with a diaphragm. In operation, the anode of the invention is in direct contact with the diaphragm so as to form mutually equivalent vertical channels defined by the surfaces of the plates, of the supporting sheets and of the diaphragm, allowing a predefined and controlled upward motion of the chlorine-brine biphasic mixture.

Anode for gas evolution reactions

A diaphragm electrolytic cell is composed of two or more overlaid modules; at least the upper modules having U-shaped anodes with diaphragm-coated cathodes housed within, allowing for a reduced electrode pitch.

Diaphragm electrolytic cell

The invention relates to a diaphragm electrolytic cell, for the production of chlorine and caustic soda having superimposed modules, and a method for increasing the electrodic surface of a diaphragm electrolytic cell constituted by a module of interdigitated anodes and cathodes which foresees an additional cell module having the same geometry as that of the original cell. The additional module is hydraulically connected in series and electrically connected in parallel to the existing module.

Diaphragm cell for chlor-alkali production with increased electrode surface and method of manufacture thereof

Object of the invention is an anodic structure for mercury cathode cells for the industrial electrolysis of sodium chloride. The new structure is constituted by a grid array comprising a multiplicity of vertically disposed and mutually parallel titanium blades, covered by an electrocatalytic coating specific for the discharge of chlorine. The ratio between the thickness and the height of the blades is comprised between 1:16 and 1:100 and the ratio between the surface of free passage between the blades and the projected surface is comprised between 15:17 and 25:30. The new grid array is perpendicularly fixed to new or existing frames having the function of mechanical support and current conduction to the grid array. Scope of the invention is simultaneously reducing the energetic consumption of the cell and the costs for restoring the exhausted electrocatalytic coating.

Anodic structure for mercury cathode electrolytic cells description of the invention

The invention discloses a novel structure for an expandable anode to be used in diaphragm cells. This new structure comprises a conductor bar in the form of a copper core provided with a titanium layer having a first and a second pair of flexible expanders fixed thereto. The welding points of the second pair of expanders are positioned orthogonally with respect to the welding points of the first pair of expanders along the circumference of the conductor bar. Also the anode surfaces are connected by welding points to the pairs of expanders. The anode of the invention may be both a new anode and a conventional existing anode having only a first pair of expanders whereto the second pair of expanders is attached. With the device of the present invention the ohmic drop between the conductor bar and the anode surface is substantially decreased and further there is no risk of damaging the interface between the copper core and the titanium coating by an excessive thermal stress, due to the welding procedures.

Anode for diaphragm electrochemical cell

A chlor-alkali diaphragm electrolysis cell comprising pairs of interleaved cathodes (C) and anodes (B), said cathodes having surfaces with openings and are provided with porous corrosion resistant diaphragms, said cell further comprising feed brine inlets and outlets (H, I, L) for the removal of produced chlorine, hydrogen and caustic, said anodes (B) are expanded by internal extenders (F) and have electrode surfaces with openings for releasing produced gaseous chlorine, characterized in that each of said expanded anodes (B) comprises a plurality of pressing means (O,Q) made of corrosion resistant material having elastic properties to maintain the electrode surfaces of the anodes against the diaphragm and said pressing means are longitudinally positioned inside the anodes having very low operating voltages.

Cell having a porous diaphragm for chlor-alkali electrolysis and process

In a process of chlor-alkali electrolysis carried out in a diaphragm cells comprising pairs of interleaved anodes and cathodes, the cathodes being provided with openings and coated with a porous diaphragm resistant to corrosion, at least part of the said anodes being provided with hydrodynamic circular to produce circulation of the anodic brine, the cell having inlets for feeding the fresh brine, and outlets for the removal of produced chlorine, hydrogen and caustic, the improvement comprising controlling the oxygen content in the chlorine and chlorate concentration in the caustic independently from the the fresh brine introduced and the concentration of the the brine by adding an aqueous solution of hydrochloric acid to the brine in the anodic compartment of the cell through a distributor positioned over the hydrodynamic circulator.

Chlor-alkali diaphragm electrolysis process and relevant cell

Operation of diaphragm monopolar electrolyzers for chlor-alkali electrolysis is improved by providing at least part of the anodes in their upper portion with hydrodynamic baffles capable of generating a plurality of lifting and downcoming recirculation motions of the mixed anolyte-gas phase and of the anolyte separated from gas, respectively, which baffles are characterized by their superior edge or overflow holes located under the free surface of the anolyte, resulting in a reduction of the cell voltage and an increase in the faradic efficiency and the quality of the products.

Growing community of inventors

Milan, Italy

Giovanni Meneghini