An electrochemical system and method are disclosed for On Site Generation (OSG) of oxidants, such as free available chlorine, mixed oxidants and persulfate. Operation at high current density, using at least a diamond anode, provides for higher current efficiency, extended lifetime operation, and improved cost efficiency. High current density operation, in either a single pass or recycle mode, provides for rapid generation of oxidants, with high current efficiency, which potentially allows for more compact systems. Beneficially, operation in reverse polarity for a short cleaning cycle manages scaling, provides for improved efficiency and electrode lifetime and allows for use of impure feedstocks without requiring water softeners. Systems have application for generation of chlorine or other oxidants, including mixed oxidants providing high disinfection rate per unit of oxidant, e.g. for water treatment to remove microorganisms or for degradation of organics in industrial waste water.
An electrolytic ozone generator includes an anode with a longitudinal edge, a cathode with a longitudinal edge spaced apart from the cathode, and an isolator. The isolator electrically separates the cathode from the anode and is semi-impermeable. The anode and cathode are impermeable for generating ozone in a flow area fluidly coupling longitudinal edges of the anode and the cathode. Ozone water apparatus, methods of making electrolytic ozone generators, and methods of generating ozone using electrolytic ozone generators are also described.
An electrolytic ozone generator includes an anode with a longitudinal edge, a cathode with a longitudinal edge spaced apart from the cathode, and an isolator. The isolator electrically separates the cathode from the anode and is semi-impermeable. The anode and cathode are impermeable for generating ozone in a flow area fluidly coupling longitudinal edges of the anode and the cathode. Ozone water apparatus, methods of making electrolytic ozone generators, and methods of generating ozone using electrolytic ozone generators are also described.
A durable composite diamond electrode is disclosed which comprise at least a relatively thicker conductive UNCD (Ultrananocrystalline Diamond) layer, with low deposition cost, on a substrate underlying a relatively thinner conductive MCD (Microcrystalline Diamond) layer. The electrode exhibits long life and superior delamination resistance under extremely stressed electrochemical oxidation conditions. It is hypothesized that this improvement in electrode reliability is due to a combination of stress relief by the composite film with the slightly “softer” underlying UNCD “root” layer and the electrochemically durable overlying MCD “shield” layer, an effective disruption mechanism of the fracture propagation between the compositing layers, and thermal expansion coefficient match between the diamond layers and the substrate. The diamond composite electrode can be applied to any electrochemical application requiring extreme voltages/current densities, extreme reliability or biomedical inertness such as electrochemical systems to generate ozone, hydroxyl radicals, or biomedical electrode applications.
The present invention relates to an apparatus for the production of ozone from water comprising at least one cell, consisting of an anode, a cathode and an interposed cation-conducting membrane, wherein the membrane conductively connects the anode and the cathode while forming flow channels for water that are separated from one another as anode and cathode chambers and wherein the flow channels are configured to allow for the recirculation of the water flow within the chambers. The present invention further relates to an electrochemical method and apparatus for producing ozone or dissolved ozone in water in high concentrations by mean of recirculation of water between at least one chamber and at least one water tank.
An electrochemical system and method are disclosed for On Site Generation (OSG) of oxidants, such as free available chlorine, mixed oxidants and persulfate. Operation at high current density, using at least a diamond anode, provides for higher current efficiency, extended lifetime operation, and improved cost efficiency. High current density operation, in either a single pass or recycle mode, provides for rapid generation of oxidants, with high current efficiency, which potentially allows for more compact systems. Beneficially, operation in reverse polarity for a short cleaning cycle manages scaling, provides for improved efficiency and electrode lifetime and allows for use of impure feedstocks without requiring water softeners. Systems have application for generation of chlorine or other oxidants, including mixed oxidants providing high disinfection rate per unit of oxidant, e.g. for water treatment to remove microorganisms or for degradation of organics in industrial waste water.
C02F 103/34 - Nature of the water, waste water, sewage or sludge to be treated from the chemical industry not provided for in groups
7.
CONDUCTIVE NANOCRYSTALLINE DIAMOND MICRO-ELECTRODE SENSORS AND ARRAYS FOR IN-VIVO CHEMICAL SENSING OF NEUROTRANSMITTERS AND NEUROACTIVE SUBSTANCES AND METHOD OF FABRICATION THEREOF
Conductive diamond micro-electrode sensors and sensor arrays are disclosed for in vivo chemical sensing. Also provided is a method of fabrication of individual sensors and sensor arrays. Reliable, sensitive and selective chemical micro-sensors may be constructed for real-time, continuous monitoring of neurotransmitters and neuro-active substances in vivo. Each sensor comprises a conductive microwire, having a distal end comprising a tip, coated with nanocrystalline or ultrananocrystalline conductive diamond, and an overlying insulating layer. Active sensor areas of the conductive diamond layer are defined by openings in the insulating layer at the distal end. Multiple sensor areas may be defined by a 2 or 3 dimensional pattern of openings near the tip. This structure limits interference from surrounding areas for improved signal to noise ratio, sensitivity and selectivity. Using fast-scan cyclic voltammetry and high speed multiplexers, multiple sensors can be arrayed to provide 3-D spatial, and near real-time monitoring.
A method is provided for operation of an electrochemical cell, comprising performing a process cycle and a regeneration cycle, which enables in situ regeneration of a diamond electrode after anodic oxidation, e.g. during electrolysis of an aqueous electrolyte at high current density. The regeneration cycle is performed upon at a predetermined process time or after detecting a condition indicative of a threshold level of anodic oxidation. The regeneration cycle comprises supplying a current to the electrodes under reverse polarity, to cause the diamond electrode to act as a cathode, and electrolyzing an electrolyte to generate hydrogen on the diamond surface of first electrode, thereby reducing the anodic oxidation and reactivating the electrode surface. Hydrogen may be generated by applying a sufficiently negative potential to the electrode during cathodic treatment in an aqueous electrolyte that is non-acidic, or weakly acidic, having a pH≥4, for example.
An electrochemical system and method are disclosed for On Site Generation (OSG) of oxidants, such as free available chlorine, mixed oxidants and persulfate. Operation at high current density, using at least a diamond anode, provides for higher current efficiency, extended lifetime operation, and improved cost efficiency. High current density operation, in either a single pass or recycle mode, provides for rapid generation of oxidants, with high current efficiency, which potentially allows for more compact systems. Beneficially, operation in reverse polarity for a short cleaning cycle manages scaling, provides for improved efficiency and electrode lifetime and allows for use of impure feedstocks without requiring water softeners. Systems have application for generation of chlorine or other oxidants, including mixed oxidants providing high disinfection rate per unit of oxidant, e.g. for water treatment to remove microorganisms or for degradation of organics in industrial waste water.
The present invention describes a microfabricated or nanofabricated structured diamond abrasive with a high surface density array of geometrical protrusions of pyramidal, truncated pyramidal or other shape, of designed shapes, sizes and placements, which provides for improved conditioning of CMP polishing pads, or other abrasive roles. Three methods of fabricating the structured diamond abrasive are described: molding of diamond into an array of grooves of various shapes and sizes etched into Si or another substrate material, with subsequent transferal onto another substrate and removal of the Si; etching of an array of geometrical protrusions into a thick diamond layer, and depositing a thick diamond layer over a substrate pre-patterned (or pre-structured) with an array of geometrical protrusions of designed sizes, shapes and placements on the surface.
B24D 3/10 - Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special natureAbrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent and being essentially inorganic metallic for porous or cellular structure, e.g. for use with diamonds as abrasives
B24D 3/16 - Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special natureAbrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent and being essentially inorganic ceramic, i.e. vitrified bondings for close grained structure, i.e. of high density
Diamond SPM and AFM probes which are durable, particularly for scanning hard surfaces such as diamond surfaces. Interlayers and seeding can be used to improve diamond deposition, and the diamond can be ultrananocrystalline diamond (UNCD). Tip sharpening improves resolution.
Diamond material made by a hot filament chemical vapor deposition process, providing large film area, good growth rate, phase purity, small average grain size, smooth surfaces, and other useful properties. Low substrate temperatures can be used. Control of process variables such as pressure and filament temperature and reactant ratio allow control of the diamond properties. Applications include MEMS, wear resistance low friction coatings, biosensors, and electronics.
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