Showing papers on "Sodium sulfite published in 1972"

Absorption of sulfur oxides from flue gas

Abstract: A method is shown for removing sulfur dioxide from a hot flue gas by absorption of the sulfur dioxide in an aqueous solution or slurry containing no more than 40 wt.% of an alkali metal carbonate or bicarbonate, preferably sodium carbonate and/or sodium bicarbonate using a spray-dryer scrubber to produce a dry mixture of sodium sulfite, sodium sulfate, and sodium carbonate and/or bicarbonate. Such a mixture is directly suitable as a feed to a regeneration stage. It is particularly preferred to regenerate the absorbent and recover commercial sulfur values in a closed-cycle process by next treating the solid absorption product in a molten salt reduction step with a reducing agent, preferably a carbonaceous material, to reduce the sodium sulfite and sulfate to sodium sulfide. Concurrently, a source of oxygen is fed to the reducer to generate sufficient heat therein for the reduction step by a combustion reaction. In the subsequent aqueous reformation step, the resulting sodium sulfide-carbonate melt from the reduction step is dissolved in water and reacted with carbon dioxide or a carbon dioxide-yielding material to form hydrogen sulfide as a recoverable product for further processing and regenerate the sodium carbonate-bicarbonate absorbent.

Sodium dithionite solution stabilization

Abstract: Sodium dithionite in solution is widely used in bleaching and vat dyeing of textiles. Unfortunately, however, losses occur not only through decomposition during dissolving of the salt in question, but also during storage of the solution. To avoid decomposition of such solutions, the presence of sulfite ion is introduced by sodium sulfite, or a comparable variant compound preferably with a pH adjustment under either aerobic or anaerobic conditions. The effect hereof in protecting the sodium dithionite against aerobic decomposition is at 7 percent to 45 percent of the decomposition rate for unprotected systems. With air exclusion, the rate in the protected system is at 2 percent to 71 percent that for the unprotected system. As indicated, mixtures of sodium sulfite or sodium bicarbonate with sodium bisulfite (anhydrous) have likewise been found effective as a stabilizing media for the sodium dithionite solution, all by virtue of the sulfite ion concentration increase therein.

Physiological parameters of growth in Saprolegnia parasitica coker

Abstract: Persistent bacteria were separated fromS. parasitica by means of the oligodynamic effect of a silver ring in a modification ofRaper's technique. Inoculation of fungal cultures was by means of mycelial macerate. Growth was measured by mycelial dry weight. A chemically defined medium (standard medium) was developed which consisted of a mineral base (chlorides of magnesium, manganese, zinc, calcium, and iron) chelated with EDTA, supplemented with glucose, sodium glutamate, and methionine, and buffered at pH 7.0 with 0.01 M. KH2PO4. Shaking culture methods supported increased growth rates and higher dry weight yields compared to stationary methods. Excellent growth occurred between 15 to 30°C. in the standard medium and between pH 4.0 and 8.0 in the standard medium plus 0.01 M. sodium succinate and 0.01 M. TRIS used as additional buffers. Significant phosphate toxicity was demonstrated at concentrations exceeding 0.05 M. Sodium succinate and TRIS, used as buffers at 0.01 M. each, were compatible withS. parasitica, whereas boric acid, sodium barbital, and sodium citrate inhibited growth under similar conditions. Substitution of other carbon sources for glucose in the standard medium (on an equal carbon basis where possible) indicated that cellobiose, dextrin, fructose, glycerine, glycogen, sodium lactate, and soluble starch supported significantly heavier growth than did the standard medium minus glucose; glycogen had a greater yield than did the standard medium minus glucose; glycogen had a greater yield than the standard medium. Arabinose, dulcitol, galactose, inulin, lactose, mannitol, mannose, raffinose, rhamnose, sorbitol, sucrose, and xylose neither stimulated nor inhibited growth; however, growth inhibition was produced by α-ketoglutaric acid, sodium citrate, and sodium succinate. When fatty acids and lipids were substituted for glucose (on an equal carbon basis where possible), only butter, lard, oleo, and palmitic acid supported heavier growth ofS. parasitica than the standard medium minus glucose. Stearicacid neither stimulated nor inhibited growth; acetic acid, butyric acid, formic acid, octanoic acid, and propionic acid significantly inhibited the growth of the fungus. Various nitrogen sources were substituted for sodium glutamate in the standard medium (on an equal nitrogen basis where possible). Casein hydrolysate and gelatin produced yields higher than that developed in the standard medium; other nitrogen sources produced lesser yields but still greater than those from the standard medium minus sodium glutamate: When various sulfur sources were substituted for methionine in the standard medium (on an equal sulfur basis), only cysteine and cystine produced dry weights comparable to that which developed in the standard medium. The following were very poor sulfur sources yet supported more growth than did the standard medium minus methionine: sodium sulfide, sodium thiosulfate, and thiourea. The ability of the other sulfur sources to support growth was questionable: potassium persulfate, sodium bisulfite, sodium dithionate, sodium hydrosulfite, sodium sulfate, sodium sulfite, and sodium thiocyanate. The standard medium contained only two nitrogen sources: sodium glutamate and methionine. Sodium glutamate served as a carbon source as well as a nitrogen source, but methionine could serve only as a source of sulfur.

Pyrite depression in coal flotation by the addition of sodium sulfite

Abstract: Pyritic sulfur flotation is depressed in aqueous flotation of a fine particle size coal fraction by adding sulfite to the flotation pulp.

Inactivation of amphotericin B by reducing agents: influences on growth inhibition of Candida albicans and lysis of erythrocytes.

Abstract: Reducing agents, both organic and inorganic, decreased the biological activity of amphotericin B. Cysteine-HCl, sodium sulfite, sodium dithionite, and sodium thiosulfate annulled amphotericin-mediated growth inhibition of susceptible organisms. These compounds also protected mouse erthrocytes from amphotericin-induced hemolysis. The reducing agents reacted, apparently irreversibly, with the heptaene chromophore of the antibiotic molecule. This reaction was reflected in altered spectrophotometric properties of the antibiotic and was associated with its loss of activity.

Treatment of waste liquor from pulp production

Abstract: A process and apparatus for treating concentrated spent liquor from a soda-based pulping process to recover sodium for reuse in the pulping process and to prevent the usual pollution of streams and air caused by the usual effluent from the pulping process. The process and apparatus comprises the following steps and apparatus. Concentrated spent liquor containing sodium is mixed with recycled finely-divided reactive alumina hydrate and formed into solid pellets by spraying the concentrated liquor-aluminum hydrate mixture onto a bed of recycled sodium aluminate furnace ash in an enclosed rotating container and tumbling the mixture and ash. The solid pellets are combusted and reacted by feeding the pellets through a furnace operating at a temperature below the fusion temperature of sodium aluminate and at a sufficiently high temperature to combust the organic portion of the pellets and react the sodium content thereof with the alumina to form additional sodium aluminate as a particulate unfused ash. The resulting furnace ash is pulverized and a portion thereof is recycled for subsequent reuse in the treating process. The remaining portion of the ash is dissolved in water to form a solution of sodium aluminate. The sodium aluminate solution is reacted with either sulphur dioxide or carbon dioxide or both to form sodium sulfite and/or sodium carbonate pulping chemical and alumina and alumina is separated for reuse in the treating process.

Synthesis of disulfide polymers of low molecular weight by repeated depolymerization

Abstract: By double or triple depolymerization with sodium hydrogen sulfide in the presence of sodium sulfite, polysulfide polymers of a very low molecular weight can be obtained from disulfide polymers prepared from bis-2-chloroethyl formal. The products are mixtures consisting chiefly of dimers and trimers with monomers. The effect of depolymerization will be greater when three depolymerization processes, instead of two, are completed with the same total amount of NaHS and Na2SO3. When depolymerization is repeated, the degree of depolymerization will be higher with polymers of a higher molecular weight. If depolymerization is made with sodium dithionite, the same effect will be achieved by either single or double depolymerization, provided that the same total amount of dithionite has been used.

Hydrogen sulfide synthesis

Abstract: A PROCESS FOR THE SYNTHESIS OF HYDROGEN SULFIDE FREE OF CARBON DIOXIDE COMPRISING THE STEPS OF REACTING A SULFUR BEARING MATERIAL SUCH AS SODIUM SULFATE OR SODIUM SULFITE WITH OXYGEN, CARBON AND STREAM UNDER REDUCING CONDITIONS IN THE PRESENCE OF HYDROGEN SULFIDE TO PRODUCE SODIUM SULFIDE. THIS SODIUM SULFIDE IS THEN REACTED WITH ACID TO LIBERATE HYDROGEN SULFIDE.

Gas Holdup and Overall Volumetric Absorption Coefficient in Bubble Columns with Suspended Solid Particles:Absorption rate of oxygen by aqueous sodium sulfite solu tion

Abstract: 固体粒子としてガラス球を懸濁させた塔径12.2および21.4cmの気泡塔内におけるガスホールドアップと触媒として銅イオンを含む亜硫酸ソーダ水溶液による酸素の吸収速度について実験した。ガスホールドアップおよび総括吸収容量係数におよぼす固体粒子径, 平均固体粒子濃度, ガス流速, 塔径およびガス分散器の種類などの影響を調べた。さらに, 単位塔容積当りの気液接触面積および平均気泡径の値を評価した。