Sodium sulfite

About: Sodium sulfite is a research topic. Over the lifetime, 2548 publications have been published within this topic receiving 18523 citations. The topic is also known as: Na2SO3 & Anhydrous sodium sulfite.

Measurement and Correlation of the Phase Equilibrium of Aqueous Two-Phase Systems Composed of Polyethylene(glycol) 1500 or 4000 + Sodium Sulfite + Water at Different Temperatures

Abstract: The equilibrium behaviors of two-phase liquid–liquid systems composed of poly(ethylene glycol) (PEG) 1500 or 4000 + sodium sulfite + water were experimentally determined at temperatures of (288.15, 298.15, 308.15, and 318.15) K. The effects of the molecular weight of PEG and the temperature on the phase separation were studied. The binodal curves were fitted to an empirical equation that correlates the concentrations of PEG 1500 or 4000 and sodium sulfite, and the coefficients for the different temperatures were estimated. The tie-line compositions were estimated and correlated using the Othmer–Tobias and Bancroft equations, and the parameters are reported. The liquid–liquid equilibrium (LLE) experimental data obtained were well-correlated to the activity coefficients of the non-random two-liquid (NRTL) and UNIversal QUAsiChemical (UNIQUAC) models, and the mean deviations were less than 0.36 % and 0.31%, respectively.

Method for permanganate bleaching of fabric and garments

Abstract: Permanganate based fabric bleaching processes, such as stone-washing processes, are substantially improved by utilizing a reducing composition comprising a metabisulfite and a sulfite in the washing step. The relative amounts of metabisulfite and sulfite in the reducing composition are selected so as to substantially eliminate the odor of sulfur dioxide during the washing step at the particular temperature selected. For washing temperatures of 100°-140 ° F. the preferred weight ratio of sodium metabisulfite to sodium sulfite is 7:3, which produces a reducing composition having a pH of 6.2 (in a 5% by weight solution). Such a composition not only allows operation at elevated temperatures without an odor of SO2, it also allows a reduction in the washing time and in the amount of reducing composition used.

Determination of nafronyl in pharmaceutical preparations by means of stopped-flow micellar-stabilized room temperature phosphorescence

Abstract: The stopped-flow mixing technique was applied to micellar-stabilized room temperature phosphorimetry by measuring the fast appearance of the phosphorescent signal yielded by nafronyl in the presence of sodium dodecyl sulfate and thallium nitrate. This mixing system diminishes the time required for the deoxygenation of micellar medium by sodium sulfite, allowing a kinetic curve that levels off within only 5 s to be obtained. Phosphorescence enhancers thallium(I) nitrate, sodium dodecyl sulfate and sodium sulfite were optimized to obtain maximum sensitivity and selectivity. A pH value of 10.5 was selected as adequate for phosphorescence development. Two rapid, straightforward and automatic methods were proposed using the slope and amplitude of the kinetic curve, which are directly proportional to the nafronyl concentration, as analytical parameters. Calibration graphs were linear for the concentration range from 30 to 600 ng ml-1. Praxilene, the only commercial formulation containing nafronyl, was analysed by both proposed methodologies. Suitable recovery values were obtained.

Concentrated multienzyme cleaning solution and preparation method thereof

Abstract: The invention discloses a concentrated multienzyme cleaning solution and a preparation method thereof, wherein the concentrated multienzyme cleaning solution is prepared from the following raw materials in parts by weight: 1 to 5 parts of organic preservative, 200 to 400 parts of surfactant, 20 to 65 parts of enzyme stabilizer, 40 to 80 parts of propylene glycol, 30 to 80 parts of triethanolamine, 10 to 60 parts of sodium sulfite, 0.1 to 5 parts of calcium chloride, 20 to 60 parts of sodium citrate, 10 to 65 parts of citric acid, 0.1 to 1 part of antifoaming agent, 30 to 80 parts of bio-enzyme, and appropriate deionized water; and the method for preparing the concentrated multienzyme cleaning solution comprises the following steps: dissolving the preservative into the propylene glycol, then adding the surfactant, the triethanolamine and the antifoaming agent into the obtained mixture so as to obtain a solution A; heating the deionized water, and dissolving the enzyme stabilizer, the sodium sulfite, the calcium chloride, the sodium citrate and the citric acid into the deionized water, then cooling the obtained mixture so as to obtain a solution bio-enzyme B; and finally, mixing thesolution A and the solution B so as to obtain the finished product of the concentrated multienzyme cleaning solution. The concentrated multienzyme cleaning solution and the preparation method thereofhave the advantages: the enzyme stabilizer is adopted to effectively protect the activity of the bio-enzyme, and used with the surfactant and the preservative, so that the obtained finished product is stable in performance, long in storage time and strong in capacity of decomposing biological tissues.