282results about "Thiosulfates/dithionites/polythionites" patented technology

A method for treating desulfurization waste liquid of a wet oxidation method. The method comprises the following steps: firstly adding a decolorant into desulfurization waste liquid for decolorizing treatment, filtering after decolorization, adding alkali into the filtrate, controlling the PH to be 8-9, performing evaporation concentration under a condition with a negative pressure, condensing the evaporated ammonia gas and water vapor to obtain concentrated ammonia liquor which can be returned to the system for recycle or be used to produce ammonium sulfate, performing fractional crystallization of the concentrated desulfurization liquid to respectively obtain high-purity sodium thiocyanate and sodium hyposulfite. The invention has a simple process, and stable operations, and effectively solves the problem of difficult HPF desulfurization waste liquid treatment in coking enterprises; the method not only reduces the discharge of the waste liquid, but also recovers a lot of chemical products with economic value, and the method has quite significant economic benefits and environmental benefits.

Inorganic oxide substrates are functionalized with silicon-free organic functionalizing agents. The organic functionalizing agent has a bonding functional group for bonding to the substrate and a functionalizing moiety that is not bonded to the substrate for imparting a desired functionality to the substrate. The functionalized inorganic oxide substrates are manufactured by selecting a functionalizing agent and reaction conditions that allows the bonding functional group to bond to the inorganic material while leaving the functionalizing moiety available for providing the desired functionality. The functionalized inorganic oxides can be used as filler materials in polymers or to manufacture a supported nanoparticle catalyst.

A process is provided for the removal of hydrogen sulfide out of a gaseous stream (22), such as a natural gas, by contacting the hydrogen sulfide containing gas with a sorbing liquid (26) containing a tertiary amine so that the hydrogen sulfide is sorbed into the liquid in absorber (11) and transferring the sorbing liquid/hydrogen sulfide mixture to a reactor (15) where the tertiary amine promotes the conversion of the hydrogen sulfide into polysulfide via reaction with sulfur; transferring the polysulfide solution from the reactor (15) to a regenerator (10) where polysulfide is converted into elemental sulfur via reaction with air (9); transferring at least a portion of the solution (25) containing elemental sulfur, as well as sulfate and thiosulfate species, into a mixture (36) where it is contacted with gaseous ammonia which reacts with the sulfate and thiosulfate species to produce ammonium sulfate and ammonium thiosulfate which are removed from the solution while the remaining portion of solution (25) is transferred to a sulfur recovery unit (14). That portion of the solution which has been subjected to ammonium sulfate and ammonium thiosulfate removal is rejoined with that portion of the solution (25) being forwarded to sulfur recovery unit (14). The solution from the sulfur recovery unit (14) is recycled back to the absorber (11).

A method and apparatus for providing an evenly mixed additive enhanced gypsum slurry to a web. Calcined gypsum and water are inserted into a mixer through at least one inlet of the mixer. The contents are agitated to form a slurry. The slurry is passed from an outlet of the mixer into a conduit. An additive is introduced into the slurry along a length of the conduit to achieve a flow stream of a slurry/additive mixture. A cross section of the flow stream is expanded in the conduit while not changing direction of the flow stream and a direction of the flow stream is changed while not expanding the cross section of the flow stream and conduit, all prior to the flow steam exiting from an outlet of the conduit.

Disclosed is a novel form of particulate precipitated aragonite, a novel process for producing it and compositions containing it.

The invention relates to a method for processing secondary salt in desulphurization waste liquid, comprising the following steps: a, carrying out pre-treatment on the desulphurization waste liquid, and removing the impurities in the desulphurization waste liquid; b, conveying the desulphurization waste liquid to a de-coloring kettle via a centrifugal pump; c, after atomizing via the nozzle of a spray dryer, drying the desulphurization waste liquid, so that Na2S2O3, Na2SO4 and NaCNS secondary salts can be separated by a manner of solid salts, and recycling the secondary salts which are adopted as inorganic salts to realize the discharge without wastewater. The method for processing the secondary salt in the desulphurization waste liquid disclosed by the invention can rationally process the waste liquid which is produced in the desulphurization step in gas production factories and has a high content of the secondary salt, realizes the discharge without wastewater, effectively recycles the waste heat of systems, realizes the reuse of the heat, reduces the production cost, has simple process and has performance of environmental-friendliness.

The invention discloses a separating method of multi-ammonia composite salt, which comprises the following steps: separating ammonia thiocyanate under low temperature (0-25 deg.c); enriching ammonium thiosulfate and ammonium sulfate under middle temperature (40-65 deg.c); separating ammonium sulfate under high temperature (80-90 deg.c); separating enriched ammonium thiosulfate at 20-40 deg.c; dissolving, crystallizing and separating solid from liquid for several times under different temperature to separate ammonium thiocyanate, ammonium thiosulfate and ammonium sulfate one by one.

A greater yield of chlorine dioxide from a chlorine dioxide generating process is obtained by providing acidic or acidity-generating components in the product chlorine dioxide solution to provide a chlorine dioxide solution having a pH below about 5.5.

Apparatus and methods of use thereof for the production of carbon-based and other nanostructures, as well as fuels and reformed products, are provided.

The present invention is process of treating mother liquid residue from sodium formate method to produce sodium hyosulfate and after being rectified to recover methanol. The process includes the following steps: 1. concentrating to obtain concentrated residue with or without sodium formate recovery; 2. incinerating the concentrated residue in a converter or one combined furnace to obtain incinerated clinker; 3. discharging high temperature clinker; 4. dissolving the clinker to form water solution; 5. absorbing SO2 from the incinerating fume with the water solution; and 6. adding sulfur to the absorbed solution to prepare sodium thiosulfate. The process can eliminate pollutant while producing sodium thiosulfate as chemical material.

A method for treating sulfide in an aqueous fluid comprises contacting the fluid with an oxidizer in the presence of a sulfur dye or sulfurized vat dye. In one embodiment, the method comprises treating sulfide contaminated water by contacting the contaminated water with air in the presence of a sulfur dye or a sulfurized vat dye. The method is useful for remediating industrial, agricultural, and municipal waste water.

Mesoporous crystalline alumina compositions and process for the preparation thereof are described. The compositions are useful as catalysts and absorbents.

The invention relates to a preparation method of analytically pure sodium thiosulfate, comprising the following steps: (1) placing distilled water and sodium sulfite into a stainless steel reactor, heating for dissolving, heating the mixed solution until boiling, slowly adding sulphur powder to the stainless steel reactor, enabling the reacted mixture to boil for 2-3 hours until the solution does not show alkalinity, stopping heating, standing for 5-6 hours, and filtering to obtain solution A; and (2) heating and concentrating the solution A into 22-33 degree Be, cooling to obtain crystals, moving the crystals into a vacuum drier to dry at 30-35 DEG C, and taking out to obtain the finished product. In the method, the analytically pure sodium thiosulfate is obtained by synthetic reaction of the sodium sulfite and the sulphur powder, thus having simple process steps, easily controlled operation and high production efficiency; and the obtained sodium thiosulfate has low impurity content, thus the product can be widely applied to the market.

The invention provides a process for reclaiming inorganic salt from wastewater in the desulphurization and decyanation of coal gas of a coke furnace. The process aims at reclaiming ammonium thiocyanate (NH4CNS), ammonium thiosulfate ((NH4)2S2O3) and ammonium sulphate ((NH4)2SO4) from wastewater produced by a liquid-phase catalytic oxidation, desulphurization and decyanation process taking ammonia as an alkaline resource. In particular, the process comprises that the wastewater and a mother solution with the ratio of NH4CNS to (NH4)2S2O3 more than or equal to 1.0 (wt) and the ratio of NH4CNS to (NH4)2S2O3 less than 1.0 (wt) are separated to obtain finished products of NH4CNS, (NH4)2S2O3 and (NH4)2SO4 through a targeted process. The process is easy to operate and control parameter, has high salt reclaiming rate and high product quality, reaches the aim that the wastewater can be fully treated and has no production of three wastes, and has good economic and social benefits.

The invention discloses a production technique for extracting ammonium thiosulfate and ammonium thiocyanate from a desulfurization waste liquor, which comprises the following steps: settling, filtering, decoloring, concentrating, crystallizing, separating, drying a sulfur-containing waste liquor generated in a desulfurization production process of HPF in a coke-oven plant, and finally, recovering ammonium thiocyanate and ammonium thiosulfate by using a mixed organic solvent. The invention is a production technique for comprehensively treating waste water generated in the prior HPF desulfurization technique, and the mixed organic solvent is used for separating ammonium thiocyanate and ammonium thiosulfate. The invention effectively solves the problem of waste water recovery in the desulfurization process, reduces discharge and environmental pollution of waste water, recovers important chemical raw materials (ammonium thiocyanate and ammonium thiosulfate), and can increase the economic benefit.

A process for continuous production of ammonium thiosulphate, (NH4)2S2O3 (ATS) from NH3, H2S and SO2 comprising steps of: (a) partial condensation in a partial condenser 4 of a first gaseous or partial liquid feed stream comprising H2O, H2S and NH3 with a molar H2S:NH3 ratio <0.4; (b) passing the aqueous condensate comprising NH4HS and NH3 from the partial condenser 4 to a reactor 9 in which said condensate is contacted with a third feed gas stream 7 comprising H2S and with an aqueous solution 10 comprising NH4HSO3 and (NH4)2SO3 under formation of an aqueous solution of (NH4) 2S2O3; (c) passing the gas stream comprising NH3 and H2S from the partial condenser 4 to a mixing device 13 in which said gas stream is completely dissolved in the water drained off from the aerosol filter 25; (d) passing a second feed gas stream 20 comprising approximately 2/3 mole SO2 per mole of NH3 contained in the first feed stream to a SO2 absorber 21 and the aerosol filter 25; (e) passing the aqueous solution produced in mixing device 13 to the SO2 absorber 21; (f) passing the off gas from the absorber 21 to the aerosol filter 25 and (g) adding to the aerosol filter 25 a balance amount of water required for obtaining approximately 40-65 wt % (NH4)2S2O3 in the aqueous of solution of (NH4)2S2O3 being withdrawn from the reactor 9.

A method of forming alpha-alane. The method includes reacting aluminum trichloride and an alkali metal hydride to form an alane-ether complex solution. An aqueous ether solution is optionally added to the alane-ether complex solution to form a partially hydrolyzed ether/alane-ether complex solution. A solution of a crystallization additive is added to the alane-ether complex solution or to the aqueous ether/alane-ether complex solution to form a crystallization solution. The crystallization additive is selected from the group consisting of squalene, cyclododecatriene, norbomylene, norbomadiene, a phenyl terminated polybutadiene, 2,4-dimethyl anisole, 3,5-dimethyl anisole, 2,6-dimethyl anisole, polydimethyl siloxane, and mixtures thereof. Ether is removed from the crystallization solution to crystallize the alpha-alane.

The invention relates to a method for extracting two secondary salts from a desulfurized salt-containing waste liquid of coke oven gas. The waste liquid treatment and secondary salt extraction process comprises the following steps: decolorizing, removing impurities, performing reduced pressure concentration on the salt-containing filtrate, separating ammonium thiocyanate, concentrating and crystallizing the ammonium thiocyanate ethanol filtrate, drying the ammonium thiocyanate product, separating ammonium sulfate, concentrating and crystallizing the ammonium thiosulfate filtrate, drying the ammonium thiosulfate product and the like. According to the invention, the desulfurized waste liquid is thoroughly treated, the products are high in recovery rate, no mixed salts or waste water is discharged, no secondary pollution is caused, and the process is clean and environment-friendly. Meanwhile, the invention also has the remarkable characteristics of high adaptability, high production elasticity, high resource utilization rate and the like.

A method for removing sulfur dioxide from flue gas and forming ammonium salts is described, along with a method for conversion of the ammonium salts into thiosulfate. Also described are an apparatus for absorbing sulfur dioxide from flue gas and an apparatus for converting ammonium salts into thiosulfate. The apparatus for absorbing sulfur dioxide from flue gas includes a multistage scrubber. The apparatus for converting ammonium salts into thiosulfate includes a fluidized bed reactor.