Abstract: Provided is a method for using selective non-catalytic reduction to reduce nitrogen dioxide in exhaust gas generated during an olefin production process. Nitrogen dioxide generated in a catalyst regeneration step of a continuous PDH process can be efficiently removed by the method of the present disclosure. Ultimately, the generation of visible fumes can be prevented through the removal of nitrogen dioxide.

Abstract: A direct air capture (DAC) system for removal of carbon dioxide from ambient air has a reaction chamber having an air intake opening and an air exhaust opening, an air movement mechanism positioned to move air from outside through the reaction chamber, utilizing the air intake and the air exhaust openings, and a mechanism introducing sodium hydroxide into the reaction chamber. Carbon dioxide in the air moved through the reaction chamber interacts chemically with the sodium hydroxide, producing sodium carbonate and water.

Abstract: Provided are a catalyst structure for ozone decomposition including a support containing a porous inorganic material, and an ?-MnO2 catalyst located on at least a portion of inner pores and a surface of the support, an air-cleaning method using the same, and an air-cleaning device and an air-cleaning system each including the catalyst structure for ozone decomposition.

Abstract: Disclosed herein are systems and methods from processing flue gas desulfurization (FGD) gypsum feedstock and ash feedstocks, either separately or together. FGD gypsum conversion comprises reacting FGD gypsum (calcium sulfate) feedstock or phosphogypsum, in either batch or continuous mode, with ammonium carbonate reagent to produce commercial products comprising ammonium sulfate and calcium carbonate. A process to separate the impurities and convert the calcium carbonate to a pure precipitated calcium carbonate is disclosed. These impurities include a concentrate of valuable Rare Earth Elements, and radioactive thorium and uranium. A process to convert calcium sulfite to calcium sulfate using oxygen and a catalyst is also disclosed. Ash conversion comprises a leach process followed by a sequential precipitation process to selectively precipitate products at predetermined pHs resulting in metal hydroxides which may be converted to oxides or carbonates.

Abstract: In an embodiment, a method for recovering carbon dioxide comprises introducing a carbon dioxide rich stream to a scrubber comprising a metal hydroxide and allowing the carbon dioxide to react with the metal hydroxide to form a metal carbonate; directing a metal carbonate stream from the scrubber to an electrochemical concentrator and applying a potential to the electrochemical concentrator to form a metal hydroxide stream and a separated carbon dioxide stream; directing the metal hydroxide stream comprising a recovered metal hydroxide and hydrogen to an electrochemical separator and applying a potential to the electrochemical separator to separate the hydrogen forming a hydrogen recycle stream from the recovered metal hydroxide forming a metal hydroxide recycle stream; and directing the separated carbon dioxide stream to a gas liquid separator and separating the separated carbon dioxide stream into a recycled water stream and a concentrated carbon dioxide stream.

Abstract: The invention relates to a process for preparing a synthetic IZM-2 zeolite, which consists in performing a hydrothermal treatment of an aqueous gel containing a source of silicon and a source of amorphous aluminium, two nitrogenous or structuring organic compounds including two quaternary ammonium functions, 1,6-bis(methylpiperidinium)hexane dihydroxide and 1,6-bis(methylpiperidinium)hexane dibromide, used as a mixture, in combination with a source of a specific alkali metal chloride M (preferably NaCl), the aqueous gel not comprising any source of at least one fluoride anion.

Abstract: A composite comprising a hydroxyapatite and at least one additive which is present during hydroxyapatite synthesis. The additive may be embedded or incorporated into or coated onto the hydroxyapatite. The additive preferably increases the hydroxyapatite porosity, e.g., providing a higher pore volume and/or BET surface area than a hydroxyapatite material without additive. The additive preferably comprises an activated carbon, chitosan, hopcalite, clays, zeolites, sulfur, and/or a metal such as Al, Sn, Ti, Fe, Cu, Zn, Ni, Cu, Zr, La, Ce, in the form of metal, salt, oxide, oxyhydroxide, and/or hydroxide. The hydroxyapatite may be calcium-deficient. The composite is in the form of particles having a D50 of at least 20 ?m, a BET surface area of at least 120 m2/g; and/or a total pore volume of at least 0.3 cm3/g. An adsorbent material comprising a composite or a blend of composite with a hydroxyapatite without additive, and its use for removal of contaminants such as Hg, Se, As, and/or B from an effluent.

Abstract: A swing bed absorption apparatus including a first absorption bed including a first plurality of solid amine based sorbent beads, a second absorption bed including a second plurality of solid amine based sorbent beads, and a solvent pump configured to alternately pump a liquid solvent through the first absorption bed and the second absorption bed. The liquid solvent is configured to alternately desorb the carbon dioxide from the first plurality of solid amine based sorbent beads and the second plurality of solid amine based sorbent beads.

Abstract: A process and a system allow producing sodium hydrosulfite crystals. A suspension containing sodium hydrosulfite is provided. The sodium hydrosulfite crystals are separated from a remainder of the suspension. The separated sodium hydrosulfite crystals are cooled to a stable temperature. The suspension may be obtained by raising a pH and lowering a temperature of a solution containing sodium hydrosulfite. A partial precipitation of the sodium hydrosulfite to form the crystals may be facilitated by addition of a nucleating agent to the suspension.

Abstract: The present invention relates to a process for producing an aqueous solution containing chlorine dioxide from gaseous chlorine dioxide and from an aqueous phase. The invention additionally relates to an apparatus for producing an aqueous solution containing chlorine dioxide and/or for carrying out the process of the invention. Finally, the invention also relates to the use of an apparatus according to the invention for carrying out a process according to the invention. In the following, all statements made in respect of the process of the invention also apply correspondingly to the apparatus of the invention and the use according to the invention, and vice versa, unless indicated otherwise in the individual case.

Abstract: Chromium particulate emissions in flue gas can be reduced or minimized by incorporating a thin layer bed of a catalyst within the flue gas flow path of a furnace, boiler, or other furnace environment that includes Cr-containing surfaces. The thin layer bed of catalyst can correspond to, for example, a honeycomb monolith with catalyst supported on the monolith surface, so as to provide a high contact area while forcing all of the flue gas to pass through the catalyst bed. The honeycomb monolith structure and the depth of the bed can be selected to provide a reduced or minimized pressure drop across the catalyst bed, such as a pressure drop of 0.25 kPa (1.0 inches of water) or less. Exposing the Cr-containing flue gas to the thin layer catalyst bed can result in a treated flue gas with a lower content of Cr.

Abstract: The process of reacting nanoscale ce-MoS2 nanosheets anchored on oxide support with lead in solution at room temperature whereby the reaction is rapid and spontaneous resulting in the formation of PbMoO4-xSx in the process of scavenging Pb2+ and Pb4+ present in the solution.

Abstract: A system and a method for reduction or elimination of environmentally harmful or “greenhouse” gases in situations in which gaseous hydrocarbons are flared or vented from an oil and gas well are disclosed. The system configures to inject a chemically reactive, or dispersive, or reactive and dispersive atomized mist into a gas flow line leading to a flare stack. The mist reacts with the gas in the flow line to convert methane to hydrogen and carbon monoxide and to reduce other harmful gases, facilitating a clean-burning, compact flare of blue color due to the presence of primarily hydrogen, some carbon monoxide, and a small amount of residual methane. The hydrogen and carbon monoxide may be captured and stored before reaching the ignition point at the top of the flare stack.

Abstract: A process is provided using a concentrated sodium bicarbonate solution as a solubilizer mixed with a calcium hydroxide to chemically produce an insoluble calcium carbonate and produce an alkaline liquid solution, then passing the alkaline liquid solution through detrimental gases in a scrubber to produce an enhanced sodium bicarbonate which regenerates the sodium bicarbonate thus creating a continuous closed loop. The process can also produce a sodium phosphate (trisodium phosphate) by mixing the alkaline liquid solution with a phosphoric acid.

Abstract: The present invention describes methods for absorbing a targeted chemical compound from a gas stream into a scrubbing solution for various uses and with various benefits. Methods are described to produce a gas stream that can be further processed with operational benefits, such as through condensing and wastewater treatment with a lower load on the wastewater treatment system. Methods are described for adsorbing the targeted compound with reduced condensation of water from the gas stream. Methods are described for producing a liquid stream comprising an absorbed form of the targeted compound for use as a saleable product, such as adsorbing ammonia for the production of a fertilizer, wherein the concentration of the absorbed form may be increased through reduced condensation from the gas stream. Methods are described for producing a lower volume liquid waste stream from the absorption process through the use of reduced condensation of the gas stream.

Abstract: The present disclosure is directed to a mixed oxide composition comprising manganese, aluminum and/or magnesium, and a rare earth element; a method of making the mixed oxide composition; a NOx adsorber comprising the mixed oxide composition; an exhaust system for internal combustion engines comprising the NOx adsorber; and a method for reducing NOx in an exhaust gas that employs the NOx adsorber.

Abstract: Systems and methods for controlling emissions from industrial sources are provided. The system includes an industrial air treatment device that captures emissions from a stack, such as an industrial flare. The industrial air treatment device does not fully encompass or enclose the stack, but allows for ambient air flow with the emissions flow. The industrial air treatment device is separate from and not incorporated into the stack. The industrial air treatment device contains fans to draw in the emissions and air flow, and filters to treat the air flow. At least one of the filters can include a water dispersal system that captures and removes pollutants. The filters can include activated carbon, demister pads, and catalytic converters. The industrial air treatment device releases the treated air to the atmosphere.

Abstract: Provided is a particulate alkaline earth metal ion adsorbent having a large adsorption capacity. The particulate alkaline earth metal ion adsorbent comprising: a potassium hydrogen dititanate hydrate represented by a chemical formula K2-xHxO·2TiO2·nH2O, wherein x is 0.5 or more and 1.3 or less, and n is greater than 0; and no binder, wherein the particulate alkaline earth metal ion adsorbent has a particle size range of 150 ?m or more and 1000 ?m or less.

Abstract: According to an embodiment of the invention, a process for substantially completely removing sulfur dioxide and ammonia from a gas stream is disclosed. The process involves lowering the vapor pressure in a scrubber by contacting the gas stream with one or more streams of re-circulating chilled media. The process further involves adjusting the pH of the process solution in the scrubber to within a predetermined range. The lowering of the vapor pressure and pH adjustment results in an increase in the solubility of sulfur dioxide and ammonia in the process solution thereby facilitating a substantially complete removal of sulfur dioxide and ammonia from the gas stream.

Abstract: An indoor smoker includes a smoking chamber and an air handler for drawing a flow of smoke from the smoking chamber through an exhaust duct. A catalytic converter is positioned in the exhaust duct and includes a catalytic element and catalytic heater for heating the catalytic element to a temperature suitable for regulating emissions from the flow of smoke. A temperature sensor is used to monitor the temperature of the catalytic element, and smoke generation is stopped when the catalyst temperature drops below a temperature threshold or drops at a rate that exceeds a threshold rate, which may be indicative of a failure of the catalyst heater or air handler.