73587 results about "Environmental chemistry" patented technology

An analyte sensor for use in connection with a biofluid is described. The analyte sensor may comprise any suitable interface between the biofluid and a derivative of the biofluid and any suitable transducer of information concerning an analyte. At least one catalytic agent is provided in a locale or vicinity of the interface. The catalytic agent, such as a proteinaceous agent or a non-proteinaceous, organic-metal agent, is sufficient to catalyze the degradation of reactive oxygen and/or nitrogen species that may be present in the vicinity of the interface. An analyte-sensing kit and a method of sensing an analyte are also described.

Process for removing mercury from flue gases of high-temperature plants, in particular power stations and waste incineration plants in which a bromine compound is fed to the multistage furnace and/or the flue gas in a plant section downstream of the furnace, the temperature during contact of the bromine compound with the flue gas being at least 500° C., preferably at least 800° C. The combustion is carried out in the presence of a sulphur compound, in particular sulphur dioxide. Subsequently to the furnace, the flue gas is subjected to an optional multistage cleanup for removing mercury from the flue gas, which cleanup comprises a wet scrubber and/or a dry cleanup.

Devices and methods for monitoring an analyte are provided. Embodiments include continuous analyte sensors having a high degree of accuracy.

An ozone generator for generating ozone by applying a specified process to oxygen by discharge includes a first raw material gas supply unit for supplying the oxygen as a first raw material gas, and a second raw material gas supply unit for supplying an oxide compound gas as a second raw material gas, in which, by excited light, excited and generated by a discharge in the oxygen and the oxide compound gas, the oxide compound gas is dissociated, or the oxide compound gas is excited accelerating dissociation of the oxygen, and ozone is generated. In this way, ozone generation efficiency is raised.

A system and method for removing both carbon-based contaminants and oxygen-based contaminants from a semiconductor substrate within a single process chamber is disclosed. The invention may comprise utilization of remote plasma units and multiple gas sources to perform the process within the single process chamber.

A system and method suitable for removing both carbon-based contaminants and oxygen-based contaminants from a substrate within a single process chamber are disclosed.

A process, system and sorbent for removal of mercury from a combustion exhaust gas stream in a combustion exhaust gas purification scheme that includes a combustion exhaust scrubber system that uses an aqueous liquid to remove acid gases from the combustion exhaust gas. A powdered mercury sorbent is used. The sorbent is introduced into the aqueous scrubber liquid in the scrubber system. After introduction of the mercury sorbent into the scrubber liquid, at least some of the mercury sorbent is separated from the scrubber liquid.

A method of sequestering carbon dioxide and producing natural gas including: (a) injecting an injectant containing at least some amount of carbon dioxide into a zone containing natural gas hydrates; (b) releasing natural gas from the hydrates by allowing thermal transfer and pressure changes from the injectant to the hydrates; and (c) sequestering the carbon dioxide in the zone that previously contained the natural gas hydrates.

Biofuels can be produced by: (i) providing a biomass containing celluloses, hemicelluloses, lignin, nitrogen compounds and sulfur compounds; (ii) contacting the biomass with a digestive solvent to form a pretreated biomass containing carbohydrates; (iii) contacting the pretreated biomass with hydrogen in the presence of a supported hydrogenolysis catalyst containing (a) sulfur, (b) Mo or W, and (c) Co and/or Ni incorporated into a suitable support to form a plurality of oxygenated intermediates, and (vi) processing at least a portion of the oxygenated intermediates to form a liquid fuel.

An adsorbent composition for removing mercury from a flue gas stream, and a method of its use. The composition is a powdered activated carbon having at least one of a halogen-containing component and an alkaline component dispersed thereon. A flow agent can be composited with the material to maintain flowability in situ.

A process for recovering CO₂ from a feed gas stream comprises treating the feed gas stream with a regenerated absorbent comprising at least one tertiary amine absorbent having a pK_a for the amino function of from about 6.5 to about 9 in the presence of an oxidation inhibitor to obtain a CO₂ rich stream and subsequently treating the CO₂ rich stream to obtain the regenerated absorbent and a CO₂ rich product stream. The feed gas stream may also include SO₂ and/or NO_x.

The present invention is directed to a process and apparatus for removing and stabilizing mercury from mercury-containing gas streams. A gas stream containing vapor phase elemental and/or speciated mercury is contacted with reagent, such as an oxygen-containing oxidant, in a liquid environment to form a mercury-containing precipitate. The mercury-containing precipitate is kept or placed in solution and reacts with one or more additional reagents to form a solid, stable mercury-containing compound.

Particulate compositions are described comprising an intimate mixture of a coal and a gasification catalyst. The particulate compositions are gasified in the presence of steam to yield a plurality of gases including methane and at least one or more of hydrogen, carbon monoxide, carbon dioxide, hydrogen sulfide, ammonia and other higher hydrocarbons. Processes are also provided for the preparation of the particulate compositions and converting the particulate composition into a plurality of gaseous products.

An electrochlorination and electrochemical system for the on-site generation and treatment of municipal water supplies and other reservoirs of water, by using a custom mixed oxidant and mixed reductant generating system for the enhanced destruction of water borne contaminants by creating custom oxidation-reduction-reactant chemistries with real time monitoring. A range of chemical precursors are provided that when acted upon in an electrochemical cell either create an enhanced oxidation, or reduction environment for the destruction or control of contaminants. Chemical agents that can be used to control standard water quality parameters such as total hardness, total alkalinity, pH, total dissolved solids, and the like are introduced via the chemical precursor injection subsystem infrequently or in real time based on sensor inputs and controller set points.

An improved multi-layered diagnostic sanitary test strip for receiving a heterogenous fluid, such as whole blood, to test for presence and/or amount of a suspected analyte in the fluid by facilitating a color change in the strip corresponding to the amount of the analyte in the fluid, wherein the test strip includes fluid volume control dams to prevent spillage of the fluid from the strip and a chemical reagent solution that facilitates end-point testing. The improved test strip comprises no more than two operative layers and: (a) a reaction membrane containing a reagent capable of reacting with the analyte of interest to produce a measurable change in said membrane; (b) an upper support layer defining a sample receiving port for receiving the fluid sample thereat; (c) one or more structures for directing the sample containing the analyte of interest through at least a portion of said reaction membrane; and (d) a lower support layer having a reaction viewing port in vertical alignment with said membrane for displaying said measurable change, said lower support being associated with said upper support to secure said reaction membrane in said test strip.

A halogen-containing gas is injected into a flowing transport air/sorbent stream at a point close to the point where the sorbent and transport air first mix to maximize the residence time available for the halogen-containing compound to be adsorbed onto the sorbent surface prior to the sorbent being injected into a flue gas containing mercury. This process maximizes the benefit and utilization of the halogen-containing reagent by placing it exactly where it is needed to facilitate elemental mercury removal—on the surface of the sorbent. The sorbent particles with their loading of adsorbed halogen-containing reagent enter the flue gas with a high reactivity for the removal of elemental mercury.

A system 26 for removing elemental mercury or mercury compounds handles carbonaceous sorbent 28 of a starter batch stored in a silo 30 in an agglomerated state. The sorbent 28 is fed by a feeder 32 to a separation device 34, which comminutes (if necessary) and de-agglomerates the sorbent particles 28 to their primary size distribution. This device 34 may be a particle-particle separator or a jet mill, where compressed air or high-pressure steam is the energy source. The de-agglomerated sorbent 28 of a contact batch created from the starter batch is conveyed by an airsteam for injection at a contact location 66 in a flue gas duct whereat carbonaceous sorbent of the contact batch adsorbs mercury from the flue gas.

Solid block alkaline detergent compositions are disclosed comprising a source of alkalinity, and other detergent additives including sequestrants. The solid block detergents of the invention used a mixed inorganic and organic sequestrant composition that successfully softens service water used in manufacturing aqueous detergents from the composition, but also obtains substantially improved organic soil removal on dishware or flatware. The solid block detergents of the invention comprise large masses of the chemical ingredients having a weight of greater than about 500 grams in a solid block product format that is typically dispensed using a spray on water dispenser that creates an aqueous concentrate that is used in a washing machine.