Showing papers on "Sodium sulfite published in 1979"

Efficacy of inactivators against 14 disinfectant substances.

Abstract: More than 24 inactivators were tested for their suitability against 14 disinfectant substances by a quantitative suspension test. Even simple inactivators were found to be efficace: 0.1% cysteine and 0.5% sodium thiosulfate for mercuric chloride and the iodophor; 0.1% sodium sulfite for these two substances and for the QAC in the lower concentration; 1.0% polysorbate 80 for hexylresorcinol, o-phenylphenol and the QAC in the lower concentration; 0.5% sodium thioglycolate for mercuric chloride, the iodophor and chloramine-T. The inactivator active against most disinfectants was the combination LPHT or 0.3% lecithin / 3.0% polysorbate 80 /0.1% histidine / 0.5% sodium thiosulfate. Also active were: LPWT (0.5% lecithin / 1.0% polysorbate 80 /1.0% Lubrol W / 1.0% sodium thiosulfate), LPT (2.0% lecithin / 2.0% polysorbate 80 / 0.5% sodium thiosulfate) and PS (3.0% polysorbate 80 / 3.0% saponin).

Process for the removal of sulphur oxides from high-chloride flue gases

Abstract: Process for removing sulfur oxides from combustion waste gas, in particular power plant waste gas, the waste gas flowing through a reaction zone which operates in the manner of a spray dryer. A cleaning liquid consisting of an aqueous solution of soda and / or sodium bicarbonate is sprayed into the reaction zone. In the reaction zone, the water content of the cleaning liquid is practically completely evaporated by the heat content of the exhaust gas and the exhaust gas is then passed through a filter. Anhydrous solid products are withdrawn from the reaction zone and the filter, which at least 75% by weight consist of sodium sulfite, sodium sulfate and sodium chloride. These solid products are processed back to soda. For this purpose, the solid products are dissolved, sulfite is oxidized to sulfate, so that a solution containing sodium sulfate and sodium chloride is formed. The sulfate is separated from this solution and the remaining solution is worked up to soda by the Solvay process.

Method of and apparatus for removing sulfur oxides from exhaust gases formed by combustion

Abstract: A process for removing sulfur oxides from exhaust gas formed by combustion particularly exhaust gas from an electricity-generating power plant. The exhaust gas flows through a reaction zone which operates like a spray dryer. A purifying liquor consisting of an aqueous solution of sodium carbonate and/or sodium bicarbonate is sprayed into the reaction zone, in which the heat content of the exhaust gases causes virtually all of the water content of the purifying liquor to be evaporated. The exhaust gas is subsequently passed through a filter. Anhydrous solids are withdrawn from the reaction zone and the filter and contain at least 75% of sodium sulfite, sodium sulfate and sodium chloride and are processed to form sodium carbonate. To that end the solids are dissolved and sulfite is oxidized to form sulfate so that a solution that contains sodium sulfate and sodium chloride is formed. The sulfate is separated from that solution and the remaining solution is used in the recovery of sodium carbonate by the Solvay process.

Methods for the recovery of sulfur components from flue gas and recycle sodium sulfite by reduction-smelting and carbonating to strip hydrogen sulfide

Abstract: An improved method for recovering sulfur from flue gas which contains sulfur dioxide formed from burning sulfur containing fuels. The method first involves the reduction burning of auxilary fuel in the presence of sodium sulfite to convert it to smelt containing sodium sulfide and sodium carbonate. The smelt is dissolved, and the solution reacted with carbon dioxide, hydrogen sulfide and water vapor forming sodium hydrosulfide. The sodium hydrosulfide is reacted with a high concentration of recycled sodium bicarbonate and stripped with carbon dioxide to form sodium carbonate and release the sulfides as hydrogen sulfide from the stripper. The hydrogen sulfide released is then converted to sulfur dioxide, sulfuric acid or elemental sulfur. Pressurized carbon dioxide is used for pressure carbonation of recycled solution from the stripper to convert the sodium carbonate to the high concentration of recycled sodium bicarbonate used for stripping. The sodium carbonate and sodium bicarbonate from the stripper are reacted under pressure with sodium bisulfite in a decarbonator to form sodium sulfite and release carbon dioxide under pressure for use in the pressure carbonation. A portion of the sodium sulfite formed by decarbonation is then reduced in the smelter. The balance of the sodium sulfite is then used for absorption of the sulfur dioxide from the flue gas forming the sodium bisulfite used for decarbonation.

Process for inhibiting crust formation in reduced dye baths

Abstract: An improved sodium hydrosulfite dye reducing composition is described for reducing vat or sulfur dye in aqueous dye bath solutions, comprised of sodium dithionite, at least 1 percent sodium sulfite by weight of sodium dithionite, and stabilized by alkali metal hydroxide, the improvement characterized by including in this composition an effective surface crust inhibiting amount of an anionic surfactant selected from the group consisting of alkyl sulfates, alkyl aryl phosphate esters, N-acyl-N-alkyl taurates, α-olefin sulfonates, alkyl aryl disulfonates, dodecylated oxydibenzene sulfonates, and mixtures thereof.

Method using lime slurry for regenerating sodium sulfite in double alkali flue gas desulfurization process

Abstract: In the process of desulfurizing flue gases in which an alkaline solution of sodium, such as sodium sulfite or sodium hydroxide, is contacted with gases in a scrubber to produce a sodium bisulfite solution, an improved method is provided for substantially reducing the time and equipment required to regenerate the sodium solution. In the method, a lime slurry stream and a sodium bisulfite stream are conflowed into a bifurcated mixing nozzle having a pair of converging inlets and a common outlet. The confluence of the streams in the nozzle creates turbulence which causes the lime slurry to react substantially instantaneously with the sodium bisulfite solution to regenerate the sodium solution which is recycled to the scrubber and a calcium sulfite precipitate which is filtered from the sodium solution and discarded.

Manufacture of sodium dithionite

Abstract: PURPOSE: To manufacture Na 2 S 2 O 4 of high purity at an improved current efficiency, by circulating hydrochloric acid soln. through an anodic chamber separated by a cation exchange membrane while feeding hydrochloric acid to the anodic chamber, and by electrolyzing aqueous sodium hydrogensulfite soln. made by supplying SO 2 to the sodium sulfite soln. in the cathodic chamber. CONSTITUTION: Aqueous hydrochloric acid soln. is circulated through the anodic chamber of an electrolytic cell having the anodic chamber separated from the cathodic chamber with a cation exchange membrane while charging hydrochloric acid soln. to the anodic chamber. On the other hand, sulfurous acid gas is supplied to the soln. contg. sodium sulfite in the cathodic chamber to form aqueous sodium hydrogensulfite which is electrolyzed thereby manufacturing catholyte contg. Na 2 S 2 O 4 . Na 2 S 2 O 4 .2H 2 O is crystallized by addition of sodium sulfite to the catholyte. To the soln. separated from the Na 2 S 2 O 4 .H 2 O is added sulfurous acid gas to form sodium hydrogensulfite, which is led to the cathodic chamber and is used for manufacturing Na 2 S 2 O 4 . This method allows to manufacture Na 2 S 2 O 4 of high purity at about 95% current efficiency. COPYRIGHT: (C)1981,JPO&Japio

Sodium sulfite regeneration method using limestone slurry

Abstract: In the Double Alkali flue gas desulfurization process wherein sodium bisulfite is produced in a scrubber from the reaction of sulfur dioxide laden flue gases with an aqueous solution of sodium sulfite, the sodium sulfite is regenerated from the sodium bisulfite by reacting the same with a limestone slurry in a bifurcated mixing nozzle having a pair of converging inlets communicating with a common outlet. The reactants are flowed into the inlets at flow rates sufficient to produce turbulence in their zone of confluence in the nozzle to initiate a reaction which, although incomplete in the nozzle, proceeds at a rapid rate to completion after the mixed reactants leave the nozzle.

Process for removal of sulfur dioxide from gas streams

Abstract: An improved apparatus and process are disclosed for the removal of sulfur oxides such as sulfur dioxide from waste gas streams. The process comprises scrubbing the waste gas with a circulating aqueous sodium sulfite/sodium bisulfite absorption solution at a relatively low pH followed by subjecting a portion of the circulating absorption solution to an improved multi-stage regeneration procedure wherein lime is employed to regenerate sulfite from bisulfite. The bleed from the scrubbing step which is subjected to regneration has a low pH and hence can dissolve more lime thereby increasing the lime utilization efficiency. In the regeneration procedure, a lime slurry is separated into a slurry of coarser lime particles and a second portion which contains very fine lime particles. The main regeneration is accomplished by adding the coarse lime slurry to the scrubber bleed. Due to the low pH in this reaction, not all the bisulfite is regenerated to sulfite. However, any remaining bisulfite is regenerated to sulfite in later regeneration steps by reaction with the second portion of the lime slurry in order to precipitate as much calcium as possible in the form of sulfate.

Oxygen trap composition

Abstract: PURPOSE:An oxygen trapping composition containing sodium sulfite, silica and/or alumina is inexpensive and clean, and useful for selective removal of oxygen in packages of food, medicines, etc. as well as for prevention of life and propagation of mold, bacilli, insects in the packaged contents. CONSTITUTION:An oxygen trapping composition consists of one part by weight of sodium sulfite (Na2SO3-7H2O), and 0.01 part, or preferably 0.05 part by weight or greater of silica and/or alumina, of which the upper limit being 100 parts by weight, or preferably 20 parts by weight or less per one part by weight of sodium sulfite. Further, the addition of 0.1 wt% filler such as active carbon is useful for the oxygen absorption velocity and quantity control and aeration improvement.

Method of preservative packaging of dried food

Abstract: PURPOSE:To provide a method of preservative packaging of dried foods using a disoxidant which generates moisture. CONSTITUTION:Dried food having a water content of less than 10% and a packaging conditioner 1 are packaged in a plastic film, the packaging conditioner containing a disoxidant 2 and a desiccant 3 (for example silicagel) with a partition wall 5 therebetween and with both of them packaged in a breathing material 6. The disoxidant 2 may comprise salts of ferrous metals or Mn with lower valence, such as ferrous sulfate, alkaline materials, such as calcium hydroxide, sulfites, such as sodium sulfite, and necessary additives. As the necessary additives, there may be mentioned metal powders, such as iron powder, absorbents, such as activated carbon, and deliquescent materials, such as manganese chloride and calcium chloride. As the breathing material a laminate material comprising paper and perforated polyethylene film is preferably used. As the plastic film packaging the dried food and the conditioner a plastic film having a lower permiability is preferred, and a composite material comprising a saponified-ethylene-vinyl acetate copolymer film is favorably used as such a film.

Pordution of block copolymer

Abstract: PURPOSE:Two-stage polymerization is conducted using a catlyst prepared by combination of cyclohexanone peroxide and a specific reducing compound to produce said block polymer useful as high-polymer modufier or material. CONSTITUTION:The first-stage polymerization of vinyl esters is conducted in the presence of a catlyst of a combination of dicyclohexanone peroxide of the formula (R is H; R' is H) resulting from the reaction of cyclohexanone with hydrogen peroxide and a reducing compound not accelerating the decomposition of the peroxy goups at all at 20-50 deg.C such as sodium sulfite. Then another monomer different from the monomer employed in the first polymerization is charge and the second-stage polymerization is effected at 60-90 deg.C to produce the objective block copolymer.

A Study of the Mechanism of the Sabattier Effect

Abstract: Conditions for producing the Sabattier effect in Eastman fine grain release positive 5302 film were established. Modifications of the second developer to develop more internal latent image by the addition of potassium iodide or to increase solution ~ physical development by the addition of sodium thiocyanate and. sodium sulfite were performed. These modifications made no significant change in the Sabattier effect. When chemical fog (from sodium borohydride) was substituted for the exposure during development , no reversal corresponding to the Sabattier effect was obtained.

Pesticidal use of N-chlorocrotyl acyl compositions

Abstract: N,N-dichloro-N-acyl compounds such as N,N-dichlorocarbamates, sulfonamides, amidosulfonamides selectively react with conjugated dienes to yield the corresponding 1,4-adducts, i.e. N-chloro-N-chlorocrotyl compounds. The N-chloro group of these adducts can be selectively reduced by aqueous sodium sulfite. Both the original and reduced adducts are effective fungicides, herbicides and bacteriocides.

Fluxing agent for concrete and mortar and process for its preparation

Abstract: A flowing agent for concrete and mortar based on lignin sulfonate and on the one hand kernsulfonierten or sulfomethylated aromatics on the other hand, in soft, the mixture of base materials and a condensation of a sulfitation has been subjected. This plasticizer is inexpensive and meets all requirements for liquefaction, setting behavior and dosage. In the manufacturing process a kernsulfoniertes or sulfomethylated aromatic may either with the addition of sulfuric acid sulfonated and then with urea and Formaldehy be condensed, or sulfited with the addition of sodium sulfite and water and then condensed with formaldehyde, after which each added lignin sulfonate, with the addition of urea and formaldehyde is condensed and sulfited with sodium sulfite. Starting from a kernsulfonierten aromatic may also initially be sulphonated with the addition of sulfuric acid, whereupon condensed with urea and formaldehyde, then sulfited, post-condensed out with the addition of Ligninsuffonat with formaldehyde and is condensed with urea.