E.i. Dupont De Nemours and Company

Monsanto Company

Kenneth B Keating

James Arthur Trainham

John Scott Newman

Clarence Garlan Law, Jr

Douglas John Eames

Arthur Hughes Graham

Francisco Jose Freire

Dennie Turin Mah

William H Zimmerman

Edward Joseph Fahy

Edward Kaoru Sakata

Stephens S The'

Ernest J Breda

The present invention relates to an electrochemical cell, system and process for converting essentially anhydrous hydrogen halide to essentially dry halogen gas. The process of the present invention is useful for converting anhydrous hydrogen halide, in particular, hydrogen chloride, hydrogen fluoride, hydrogen bromide and hydrogen iodide, to a halogen gas, such as chlorine, fluorine, bromine, or iodine. In particular, in the present invention, water is provided to the cation-transporting membrane at the cathode in various ways. The present invention allows for recovery of a released fluid at the cathode-side of the membrane and recycling of the released fluid back to the cathode side of the membrane. In this way, the recovered, released fluid may be recycled to continuously supply water to the membrane, thereby allowing the limiting current density of the cell to be increased and/or controlled.

Membrane hydration in electrochemical conversion of anhydrous hydrogen

Carbonyl halide is produced from carbon monoxide and halogen produced from the electrochemical conversion of anhydrous hydrogen halide. Both the oxidation of anhydrous hydrogen halide and the formation of carbonyl halide are carried out in the anode-compartment of an electrochemical cell. This reduces the equipment and thus the capital investment necessary for carrying out these reactions. Moreover, no catalyst is needed to form halogen and subsequently make carbonyl halide, as in the prior art. In addition, the health hazards associated with making a carbonyl halide, such as phosgene, at high temperatures from chlorinated hydrocarbons with atmospheric oxygen are virtually eliminated. Furthermore, the halogen produced as a result of the oxidation of anhydrous hydrogen halide are dry, thereby eliminating the need for a preheater before the halogen is reacted with carbon monoxide. Thus, with the present invention, carbonyl halide may be produced more easily, more safely and more inexpensively as compared to prior art processes.

Method for and apparatus production of carbonyl halide

The present invention relates to an electrochemical cell and a process for producing a hydroxide solution, sulfuric acid and a halogen gas from a hydrogen halide and a sulfate solution. In particular, the sulfate solution may be an alkali metal sulfate solution, such as sodium or potassium sulfate solution, an alkaline earth metal sulfate solution or an ammonium sulfate solution. The cell and the process may use either an anhydrous or an aqueous hydrogen halide, namely, hydrogen chloride, hydrogen fluoride, hydrogen bromide and hydrogen iodide, to a respective dry halogen gas, such as chlorine, fluorine, bromine, or iodine, to produce hydrogen ions in order to split the alkali metal solution and form the sulfuric acid. The cell has two membrane-electrode assemblies, where an anode is disposed in contact with one membrane, and a cathode is disposed in contact with another membrane. The sulfate solution is fed in between the membrane-electrode assemblies.

Electrochemical cell and process for splitting a sulfate solution and

A particular anode comprising an electrochemically active material selected from the group consisting of the oxides of the elements tin, germanium and lead and mixtures comprising at least one of the respective oxides of such elements is useful in an electrochemical cell for the direct production of essentially dry halogen gas from essentially anhydrous halogen halide, or in a process for such production of essentially dry halogen gas. This cell or process may be used to produce halogen gas such as chlorine, bromine, fluorine and iodine from a respective anhydrous hydrogen halide, such as hydrogen chloride, hydrogen bromide, hydrogen fluoride and hydrogen iodide.

Anode useful for electrochemical conversion of anhydrous hydrogen halide

The invention relates to a process for electrochemically converting anhydrous hydrogen halide, such as hydrogen chloride, hydrogen fluoride, hydrogen bromide and hydrogen iodide, to essentially dry halogen gas, such as chlorine, fluorine, bromine and iodine gas, respectively. In a preferred embodiment, the present invention relates to a process for electrochemically converting anhydrous hydrogen chloride to essentially dry chlorine gas. This process allows the production of high-purity chlorine gas. In this process, molecules of essentially anhydrous hydrogen chloride are transported through an inlet of an electrochemical cell. The molecules of the essentially anhydrous hydrogen chloride are oxidized at the anode of the cell to produce essentially dry chlorine gas and protons, which are transported through the membrane of the cell. The transported protons are reduced at the cathode to form either hydrogen gas or water.

Electrochemical conversion of anhydrous hydrogen halide to halogen gas

A process for producing thin films of superconducting material by bombarding a heated target with radiation from pulsed high energy UV laser to form a plume of target material, and depositing the plume on a substrate is disclosed.

Process for making oxide superconducting films by pulsed excimer laser

A plating bath and process for electroplating coatings of palladium nickel alloys on a conductive substrate at current densities in the range of 10 amps/sq. ft. to 150 amps/sq. ft. wherein the palladium content of the alloy remains substantially constant despite current density variations during plating. The alloy composition stability is achieved by adding at least about 15 parts per million of iodide and/or iodate ions to the plating bath. The as-plated alloy has a thin surface layer which contains iodide at or near the surface.

Alloy coatings for electrical contacts

A plating bath and process for electroplating coatings of palladium nickel alloys on a conductive substrate at current densities in the range of 10 amps/sq. ft. to 150 amps/sq. ft. wherein the palladium content of the alloy remains substantially constant despite current density variations during plating. The alloy composition stability is achieved by adding at least about 15 parts per million of iodate ions to the plating bath.

Electroplating bath and process for maintaining plated alloy composition

A plating bath and process for electroplating coatings of palladium nickel alloys on a conductive substrate at current densities in the range of 10 amps/sq. ft. to 150 amps/sq. ft. wherein the palladium content of the alloy remains substantially constant despite current density variations during plating. The alloy composition stability is acheived by adding at least about 15 parts per million of iodide ions to the plating bath.

A process for separating anions, such as sulfates, chlorides and phosphates, and cations, such as ammonium and hydrogen ion, from methionine hydroxy analogue hydrolysate in solution by passing a direct electric current through an electrodialysis cell, said process producing substantial environmental benefits and energy savings over existing methods of manufacture.

Growing community of inventors

Wilmington, DE, United States of America

Kenneth B Keating