High strength, low salt solutions of alkali hypochlorite (e.g. sodium hypochlorite) can advantageously be produced in a system comprising a subsystem in which alkali hydroxide solution and chlorine are reacted to produce alkali hypochlorite and salt solids in a crystallizer, while drawing a vacuum in the crystallizer. In a system comprising a chlor-alkali plant, the alkali hydroxide solution and chlorine can be directly obtained (i.e. without concentrating) from the electrolyzer in the plant. A net energy savings in the system can be achieved and water consumption in the chlor-alkali plant can be substantially decreased by returning chlorinated condensate from the crystallizer to the recycle line in the chlor-alkali plant. Salt can be efficiently recovered by redissolving the salt solids produced in depleted brine and returning it directly to the electrolyzer. As a result, high strength, low salt hypochlorite can be produced without the need to evaporate caustic.

To provide a production method and a production apparatus of a sodium hypochlorite solution that can produce a sodium hypochlorite solution with a high available chlorine concentration at a low cost using an on-site facility. In production of a sodium hypochlorite solution by feeding secondary salt water as an aqueous sodium chloride solution, in an electrolyzer 10 comparted into an anode chamber 2 and a cathode chamber 3 by an ion-exchange membrane 1, to the anode chamber and, after electrolysis, introducing an anolyte and a generated chlorine gas in the anode chamber and an aqueous sodium hydroxide solution generated in the cathode chamber into a reaction tank 20 to allow the anolyte, the chlorine gas, and the generated aqueous sodium hydroxide solution as a catholyte to react in the reaction tank, a primary salt water generation step of dissolving raw salt G containing sodium chloride as a main component in purified water B to generate primary salt water, and a chelating step of chelating the primary salt water to generate secondary salt water A are included, in which a decomposition rate of salt ranges from 80 to 95%.

Methods for representing crystal structure of inorganic materials in matrix form, and for quantitative comparison of multiple inorganic materials, can be employed to identify candidate materials with high potential to possess a desired property. Such methods can include conversion of an atomic coordinate set to a coordinate set for an anion only lattice, anion substitution, and unit cell re-scaling. Such methods can further include simulation of x-ray diffraction data for modified anion-only lattices, and generation of n2 matrices from the simulated diffraction data. Quantitative structural similarity values can be derived from the n2 matrices. The quantitative structural similarity values can be useful for structural categorization, as well as prediction of functional properties.

Apparatuses, systems, and methods for removing acid gases from a gas stream are provided. Gas streams include waste gas streams or natural gas streams. The methods include obtaining a hypochlorite and a carbonate or bicarbonate in an aqueous mixture, and mixing the aqueous mixture with the gas stream to produce sulfates or nitrates from sulfur-based and nitrogen-based acidic gases. Some embodiments of the present disclosure are directed to produce the carbonate and/or bicarbonate scrubbing reagent from CO.sub.2 in the gas stream. Still others are disclosed.

A process for substantially reducing the corrosiveness of a composition containing in situ generated sodium hypochlorite in which the sodium hypochlorite is substantially converted to a haloamine.

The present invention provides compositions comprising comminuted sodium hypochlorite pentahydrate crystals with an average length-to-diameter ratio of less than about 20:1, and a mother liquor saturated in sodium hypochlorite, which has excess alkalinity and/or one or more additional alkali or alkali earth metal salts. Processes for preparing these compositions will be presented.

Apparatuses, systems, and methods for removing acid gases from a gas stream are provided. Gas streams include waste gas streams or natural gas streams. The methods include obtaining a hypochlorite and a carbonate or bicarbonate in an aqueous mixture, and mixing the aqueous mixture with the gas stream to produce sulfates or nitrates from sulfur-based and nitrogen-based acidic gases. Some embodiments of the present disclosure are directed to produce the carbonate and/or bicarbonate scrubbing reagent from CO.sub.2 in the gas stream. Still others are disclosed.

High strength, low salt solutions of alkali hypochlorite (e.g. sodium hypochlorite) can advantageously be produced in a system comprising a subsystem in which alkali hydroxide solution and chlorine are reacted to produce alkali hypochlorite and salt solids in a crystallizer, while drawing a vacuum in the crystallizer. In a system comprising a chlor-alkali plant, the alkali hydroxide solution and chlorine can be directly obtained (i.e. without concentrating) from the electrolyzer in the plant. A net energy savings in the system can be achieved and water consumption in the chlor-alkali plant can be substantially decreased by returning chlorinated condensate from the crystallizer to the recycle line in the chlor-alkali plant. Salt can be efficiently recovered by redissolving the salt solids produced in depleted brine and returning it directly to the electrolyzer. As a result, high strength, low salt hypochlorite can be produced without the need to evaporate caustic.

To provide a method and an apparatus for producing a sodium hypochlorite solution on-site at a high efficiency and at the initial cost and suppressing operating cost without any problems about impurities derived from raw material water and raw salt. A method of producing a sodium hypochlorite solution on-site in the vicinity of a physical plant where a sodium hypochlorite solution is used. In production of a sodium hypochlorite solution by feeding secondary salt water, in an electrolyzer comparted into an anode chamber and a cathode chamber with an ion-exchange membrane, to the anode chamber and allowing components in the anode chamber and the cathode chamber after electrolysis to react in a reaction tank, there are included respective steps of treating raw material water A with a cation-exchange resin B to generate purified water 5, dissolving raw salt D in the purified water to generate primary salt water E, performing an examination for confirming the presence or absence of a precipitate or suspended solid in the primary salt water, and directly performing chelating in the case of no precipitate or suspended solid contained in the primary salt water, or performing chelating after addition of an acid component for dissolution of the precipitate or suspended solid in the case of the precipitate or suspended solid contained therein, to generate secondary salt water 4.

The electrochemical reactors disclosed herein provide novel oxidation and reduction chemistries and employ increased mass transport rates of materials to and from the surfaces of electrodes therein.