Cem Corporation

William Edward Jennings

Edward Earl King

David A Barclay

Joseph Joshua Lambert

David L Herman

James Edward Thomas

Wyatt Price Hargett, Jr

Matthew Donald Barrett

Michael J Collins

Timothy A Zawatsky

Ian Goldstein

Cindy Rushing Moser

Dennis Palmer Manchester

David Deese

Todd Mark Hochrad

Steven Francis Guilmette

Cap for a reaction vessel or the like

A volatile content analysis instrument is disclosed that includes a cavity and a microwave source positioned to produce and direct microwaves into the cavity at frequencies other than infrared frequencies. A balance is included with at least the balance pan (or platform) in the cavity. An infrared source is positioned to produce and direct infrared radiation into the cavity at frequencies other than the microwave frequencies produced by the microwave source. A lens is positioned between the infrared source and the balance pan for more efficiently directing infrared radiation to a sample on the balance pan. The lens has dimensions that preclude microwaves of the frequencies produced by the source and directed into the cavity from leaving the cavity.

Moisture and volatiles analyzer

A venting cap is disclosed for pressure vessels for microwave-assisted chemistry. The venting cap includes a flexible circular cover for closing the mouth of a reaction vessel, a flexible annular wall depending from the circular cover, and a flexible annular ring at the bottom of the annular wall and parallel to the circular cover for positioning the cap on a reaction vessel. At least one indentation in the circular cover minimizes distortion when any contents of a reaction vessel exert pressure against the cap, and at least one opening in the annular wall provides a ventilation path through the cap when gas pressure in a reaction vessel flexes the cap sufficiently to partially disengage at least a portion of the cap from the mouth of the reaction vessel.

Pressure stepped microwave assisted digestion

An instrument and method for high pressure microwave assisted chemistry are disclosed. The method includes the steps of applying microwave radiation to a sample in a sealed vessel while measuring the temperature of the sample and measuring the pressure generated inside the vessel and until the measured pressure reaches a designated set point, opening the vessel to release gases until the pressure inside the vessel reaches a lower designated set point, closing the vessel, and repeating the steps of opening the vessel at designated pressure set points and closing the vessel at designated pressure set points to the sample until the sample reaction reaches a designated high temperature. The designated set points can controllably differ from one another as the reaction proceeds. Microwave energy can be applied continuously or intermittently during the opening and closing steps. The apparatus includes a microwave cavity, a microwave transparent pressure resistant reaction vessel in the cavity, a cap on the reaction vessel, a pressure sensor for measuring pressure in the vessel, a temperature sensor, and means for opening and closing the cap at predetermined pressure set points measured by the pressure sensor to release pressure from the vessel.

A pressure-measuring vessel system for microwave assisted chemical processes is disclosed. The vessel system includes a pressure resistant vessel that is otherwise transparent to microwave radiation, a pressure-resistant closure for the mouth of the vessel, with portions of the closure including a pressure resistant synthetic membrane, a pressure transducer external to the vessel, and a tube extending from the transducer, through the membrane and into the vessel for permitting the pressure inside the vessel to be applied against the transducer while the closure and membrane otherwise maintain the pressure resistant characteristics of the vessel.

Pressure measurement in microwave-assisted chemical synthesis

A pressure-sealing, pressure-monitoring closure for non-invasively sealing a reaction vessel to a defined release pressure in microwave-assisted chemistry is disclosed. The closure includes a pressure-resistant, microwave-transparent reaction vessel, one portion of which defines a mouth, a flexible pressure-transmitting releasable cover assembly on the mouth of the vessel, a pressure transducer on the cover and external to the vessel for monitoring the pressure in the vessel as exerted against the flexible cover, and a clamp for urging the vessel, the cover and the transducer together under a defined force so that when the pressure in the vessel exceeds the defined force, the cover can flex and release the pressure from the vessel.

Pressure measurement and relief for microwave-assisted chemical reactions

An instrument is disclosed for microwave-assisted chemical processes that avoids tuning discrepancies that otherwise result based upon the materials being heated. The instrument includes a source of microwave radiation, a waveguide in communication with the source, with at least a portion of the waveguide forming a cylindrical arc, a cylindrical cavity immediately surrounded by the cylindrical arc portions of the waveguide, and at least three slotted openings in the circumference of the circular waveguide that provide microwave communication between the waveguide and the cavity.

Microwave-assisted chemical synthesis instrument with fixed tuning

A method is disclosed for carrying out microwave-assisted chemical reactions. The method includes the steps of adding reagents to a pressure-resistant microwave-transparent vessel, securing the vessel against pressure release with a penetrable septum made of a material that can be penetrated by a needle while surrounding and sealing against the needle even after penetration to thereby maintaining the pressure integrity of the vessel, thereafter inserting a needle through the penetrable septum and into the pressure-secured vessel to provide fluid communication to the interior of the scaled pressure-resistant vessel through the needle, applying mechanical pressure against the septum while the needle is inserted therethrough, and irradiating the vessel and its contents with microwaves with the needle inserted therein.

An instrument for microwave-assisted chemical processes is disclosed that provides greater flexibility in carrying out microwave-assisted chemistry under varying conditions. The instrument includes a source of microwave radiation, and a cavity in communication with the source, with the cavity including at least one wall formed of two engaged portions that form a barrier to the transmission of microwaves when so engaged. The engaged portions are disengagable from one another, and one of the portions includes a microwave-attenuating opening.

Growing community of inventors

Wingate, NC, United States of America

William Edward Jennings