Abstract: Carbon fibers having substantially increased active surface area and total surface area are used to enhance carbon fiber bonding to matrix materials in carbon fiber products. The enhanced active surface area and total surface area are produced by carbon removal in disordered regions as well as perfect basal plane regions by catalytic silver oxidation.

Abstract: Method for controlling N.sub.2 O emissions from stationary combustion systems having variable flue gas temperatures are disclosed. The N.sub.2 O emissions are controlled by the introduction of a N.sub.2 O control agent, such as an alkaline compound, into the effluent stream. In addition, the present invention discloses methods for controlling N.sub.2 O emissions from stationary combustion systems having variable flue gas temperatures while reducing NO.sub.x emissions. Use of an NO.sub.x reducing agent and an N.sub.2 O control agent, such as urea and monosodium glutamate, enlarges the temperature window for effective selective noncatalytic NO.sub.x reduction while significantly eliminating N.sub.2 O emissions commonly experienced with urea injection. Further, the present invention discloses methods for controlling N.sub.2 O emissions from stationary combustion systems having variable flue gas temperatures while reducing SO.sub.x emissions. Use of an NO.sub.x reducing agent, an SO.sub.

Abstract: A process for removing sulfur dioxide from flue gases where calcium sulfate and magnesium hydroxide are produced, with the magnesium hydroxide separated in an impure state and purified by addition of water thereto to dissolve contaminant calcium sulfate. The calcium sulfate preferentially dissolves to form an aqueous solution and purified magnesium hydroxide is separated therefrom. At least a portion of the resultant aqueous solution of calcium sulfate is returned to the wet scrubbing system as make-up water to replenish water lost from the aqueous medium during scrubbing of the flue gases.

Abstract: A method and apparatus of scrubbing acid gas from flue gas comprises slats which define a moving bed of scrubbing material which is capable of reacting with the acid gas to form reaction products on particles of the scrubbing material. Flue gas from a boiler or other sources of flue gas is passed through the moving bed of scrubbing material. The scrubbing material is sprayed with water to the saturation point for increasing the rate of reaction between the reaction gas on the scrubbing material. The scrubbing material leaving the bottom of the moving bed is subjected to a separation step which removes the reaction products as fine dust which is disgarded, and returns the now regenerated particles of scrubbing material to the top of the moving bed.

Abstract: Method of extracting dinitrogen pentoxide (N.sub.2 O.sub.5) from its mixture in nitric acid, which consists of providing a solution of the mixture in an inert organic solvent, stripping out the N.sub.2 O.sub.5 from solution in a carrier gas stream containing ozone, and subsequently condensing the N.sub.2 O.sub.5 out of the gas stream by contact with further inert organic solvent. The presence of ozone suppresses the dissociation of the N.sub.2 O.sub.5 transferred to the gas stream into dinitrogen tetroxide (N.sub.2 O.sub.4). In a preferred embodiment the stripping and absorbing steps take place continuously in adjacent stripping and absorbing columns respectively having organic solvent recirculating through each.

Abstract: Sulfur dioxide is removed from a gaseous stream by contact with a lime slurry which contains sulfur to produce thiosulfate ions and 2,000-10,000 ppm of effective sodium ions to effect removal of the sulfur dioxide A bleed stream, removed from the scrubbing loop has calcium sulfite solids removed therefrom while separated liquor is returned to the scrubbing loop.

Abstract: A regenerable flue gas desulfurization system whose end product is preferably a commercial quality gypsum (such as for use in wallboard or the like) or other product easily landfilled. Accordingly, sulfur containing flue gas is passed through an absorber where it is sprayed with a solution so as to initiate certain chemical reactions thereby stripping it of sulfur. Any alkali in this sulfur-containing solution is recovered and returned to the absorber with the remainder of this solution being oxidized in an oxidation/recirculation tank. The slurry from this tank may be recycled to a pre-absorber for chlorine removal if desired, otherwise, a portion of this slurry is sent for the recovery of gypsum.

Abstract: A flue gas desulfurization process for treating flue gases containing SO.sub.2, NO.sub.x, and halogen gases by the wet lime method, in which part of the absorbent liquid is extracted, freed from iodine, and recycled as makeup water to the absorption column.

Abstract: The present invention relates to processes and apparatus for mixing oxidizable reactants with oxidant and oxidizing oxidizable reactants. When ammonia is used as the reactant, nitric acid can be obtained. Through using particular mixing and oxidizing arrangements, the volume of reactant oxidized can be significantly increased.

Abstract: The subject invention relates to a method for combined reduction of the concentrations of nitrogen oxides (NOx) and carbon monoxide (CO) formed in fossil fuels combustion process in combustion apparatus and fuels combustion devices, such as automotive and stationary internal combustion engines, gas turbines, fuel fired power boilers and heaters, among others, by the reduction process conversion of NO to harmless N.sub.2 and water, combined with oxidation of CO to carbon dipoxide (CO.sub.2), which is subsequently discharged in the effluent combustion products gasea into the ambient air atmosphere.

Abstract: NO.sub.x removal is accomplished by contacting a NO.sub.x -containing stream under reducing conditions with a urea-ammonia-water composition.

Abstract: Processes for the removal of sulfur dioxide from gas streams, e.g., stack gases, are disclosed wherein the absorption occurs in the presence of a diamine. The first amine group, i.e., stronger amine group, of the diamine is in salt form, having sulfite anions associated therewith, and absorbs by a sulfite/bisulfite absorption mechanism. The second amine groups absorbs sulfur dioxide in free base form. The sulfite salt on the first amine group is maintained by controlling the level of heat stable salts in the absorbent. Both the first and second amine groups can be conveniently regenerated together, e.g., by steam stripping.

Abstract: An improved wet magnesium-enhanced lime flue gas desulfurization system and process are provided. The magnesium-enhanced lime slurry process for removing sulfur dioxide from flue gas to produce gas that is substantially free from sulfur dioxide and calcium and sulfite-containing waste solids is modified to include the addition of process reagents to a separate premix slurry tank which has a controlled, high pH. The addition of slurry formed from the scrubber effluent to the premix slurry tank is controlled to maintain the pH above 10. The premix slurry tank mixture is circulated to a reaction tank for reaction with the scrubber effluent to produce large crystal, easily dewatered waste solids.

Abstract: The invention describes a process for catalytically destroying NOx and carbon monoxide present in oxygen-containing combustion products wherein methane serves as a reductant. The process comprises combusting a fuel source in the presence of oxygen to form combustion products comprising nitrogen oxides, carbon monoxide and oxygen; introducing methane into the combustion products in an amount such that the total amount of methane to nitrogen oxides present, expressed as a ratio, by volume is greater than about 0.1; and reacting the nitrogen oxides, carbon monoxide, methane and oxygen in the presence of an exchanged crystalline zeolite under conditions sufficient to convert the nitrogen oxides and carbon monoxide to gaseous nitrogen, water and carbon oxides. Suitable catalysts include zeolites having a silicon to aluminum ratio of greater than or equal to about 2.

Abstract: A method is provided for reducing NO.sub.x for high flow applications such as NO.sub.x abatement in an exhaust gas from an internal combustion engine operating under lean burn conditions wherein NO.sub.x is reduced by hydrocarbon reductants. The method employs a hydrothermally stable catalyst comprising transition metal-containing ZSM-5 which is prepared by in-situ crystallization of an aggregate comprising ZSM-5 seeds, silica, and a crystalline silicate.

Abstract: A desulfurization process which comprises the steps of bringing a combustion exhaust gas into contact with a gypsum slurry containing 1% or less of calcium carbonate in a first absorption tower, and then bringing the combustion exhaust gas into contact with a gypsum slurry containing 1% or more of calcium carbonate in a second absorption tower. SO.sub.x can be removed from a combustion exhaust gas with a high efficiency in accordance with a wet lime/gypsum method.

Abstract: A process for producing large, regularly-shaped crystalline calcium sulfite solids in a wet calcium-based flue gas desulfurization system is provided. A chemical crystal modifier, preferably an organophosphonate, is added to the calcium sulfite-containing solids slurry produced by the FGD process under inhibited oxidation conditions at an addition level which promotes the formation of large, regular calcium sulfite crystals that are easily dewatered.

Abstract: Process and apparatus for removal of sulfur oxides from flue gases.In the process, a NaOH solution is injected into flue gases containing calcium oxide so that the formed reaction products are discharged from the reactor in a dry dust-like form together with the flue gases, whereafter the solids present in the flue gases are separated from the flue gases, mixed with water and sodium so as to form a sodium hydroxide solution wherefrom the other reaction products in solid form can be removed, the sodium hydroxide solution being returned to the flue gases.The apparatus comprises a desulfurization reactor (3) wherein a sodium hydroxide solution is injected into the flue gases, and an electrostatic precipitator (5) wherein the dust-like solids are separated from the flue gases.

Abstract: Process for the removal of cadmium from solutions of phosphoric acid derived by the sulphuric and nitric digestion of phosphatic rocks, including the following steps:adding to the phosphoric acid solution bromide ions, such as hydrogen bromide or the bromides of alkaline metals, in quantities ranging from 100 to 3500 ppm;adding to the same solution of at least one condensed polyphosphatic compound in a concentration of 1 to 5% by weight;eluting the mixture thus obtained through at least two beds of an ion-exchange resin with a styrene divinylbenzene matrix at a temperature ranging from 15.degree. to 50.degree. C.

Abstract: In the process for the production of oxygen by adsorption, the following combination of steps are used: the number of adsorbers is at least three; the time of pumping y under sub-atmospheric pressure during step b) is higher than dephasing T/n, and at least equal to the time x of the production step; the phase of pumping of the column of adsorbent material is carried out by using on said adsorption column successively at least two systems of pumping wherein one is in operation from the start of the pumping operation, another one is adapted to operate until pumping is over.