Sulfite test

Neutral salts (e.g., zinc, lead, cadmium salts) considerably reduce the sensitivity of this sulfite test. Consequently, it is not feasible to prevent the interference due to sulfides (and hydroxides) by adding of ZnS04, etc. 

Sulfite, Test with malachite green, see page 447. 

Sulfur. Molten - 775 300-315 284-302 265-295 412 149-157 140-150 129-146 G S E E S — - plus aerated water at pH of 1.5 to 3.5.11-day test period in surface pipe line between well and gathering station. Alloy C - 0.9 mpy, 6-day test period agitated, plus air and impurities including sulfuric acid, and feme sulfite-Tested up to 12 days... 

Analytical and Test Methods. Analysis and test methods are similar to those for sodium thiosulfate. Sulfite is determined by an indirect method based on the titration of the acid Hberated when both the sulfite and thiosulfate are oxidized with iodine solution (69). 

The value of the coefficient of heat transfer from steam to sheet is determined by the conditions prevailiug on the inside and on the surface of the dryers. Low coefficients may be caused by (1) poor removal of air or other noncoudeusables from the steam in the cyhn-ders, (2) poor removal of condensate, (3) accumulation of oil or rust on the interior of the drums, and (4) accumulation of a fiber lint on the outer surface of the drums. In a test reported by Lewis et al. [Pulp Pap. Mag. Can., 22 (Februaiy 1927)] on a sulfite-paper diyer, in which the actual sheet temperatures were measured, a value of 187 W/(m °C) [33 Btu/(h ft" °F)j was obtained for the coefficient of heat flow between the steam and the paper sheet. 

Reactions between A -(l-chloroalkyl)pyridinium chlorides 33 and amino acids in organic solvents have a low synthetic value because of the low solubility of the amine partner. A special protocol has been designed and tested in order to circumvent this drawback. Soon after the preparation of the salt, an aqueous solution of the amino acid was introduced in the reaction medium and the two-phase system obtained was heated under reflux for several hours. However, this was not too successful because sulfur dioxide, evolved during the preparation of the salt, was converted into sulfite that acted as an 5-nucleophile. As a result, A -(l-sulfonatoalkyl)pyridinium betaines such as 53 were obtained (Section IV,B,3) (97BSB383). To avoid the formation of such betaines, the salts 33 were isolated and reacted with an aqueous solution of L-cysteine (80) to afford thiazolidine-4-carboxylic acids hydrochlorides 81 (60-80% yields). 

The sulfite oxidation is a recommended test reaction for determining the size of the specific interfacial area in gas/liquid systems, in particular as expressed by the a value [9, 10]. 

M sodium chloride (NaCI) 0.2M sodium sulfate (Na2S04) 0.2M sodium sulfite (Na2S03) 0.2M lead(ll) nitrate (Pb(N03)2) 0.2M zinc nitrate (Zn(N03)2) test tubes (10) test-tube racks (2) thermometer 10-mL graduated cylinder... 

CAUTION Perform this reaction in the fume hood. Pour 3 mL of 0.2M sodium sulfite into a clean test tube. Slowly add 1 mL of... 

Any sulfate ions resulting from oxidation of sulfite should be removed otherwise they will be converted to sulfuric acid in the subsequent procedure and destroy sultone. Ordinarily, 12-13 g. of barium chloride dihydrate is required. The end point of the addition is conveniently determined with tetrahydroquinone indicator used in spot tests on filter paper [cf. Ind. Eng. Chem., Anal. Ed., 9, 331 (1937)]. 

Diethyl sulfite reaction, 10 530 Diethyltoluenediamine (DETDA), 25 197 Dietzeite, 6 471t Difasol process, 26 899 Difenzoquat, 13 322 Difference spectroscopy, 14 236 23 144 Difference tests, in flavor characterization, 11 512... 

Kubeck and Naylor [2] tested four chemical preservatives (formaline, sulfite, bisulfite and a mixture of formaline/sulfite) by analysing NPEOs in river water over a period of 4 weeks. The sulfite- and bisulfite-preserved samples deteriorated drastically beginning after the first week, dropping 60-80% in NPEO concentration after four weeks. Formaline maintained the NPEO concentration within 10% of the original through at least two weeks. Formaline/sulfite mixture showed 25% loss after four weeks. 

Data for magnesia-enhanced limestone scrubbing of SO2 by a Turbulent Contact Absorber were obtained from the 10-MW equivalent EPA Alkali Scrubbing Test Facility. These data and the chemical model have been used to predict the enhancement effect of magnesia-induced dissolved sulfite concentration on S02 removal. 

Warning is given that sodium sulfite may not remove all peroxidic compounds if peroxyacids are present, with which it can form undetectable, but unstable, complex peroxides [19], Peroxide test strips may not be sufficiently reliable as the sole means of testing for presence of peroxides in a wide range of peroxidisable liquids. It was recommended that an additional test (potassium iodide-acetic acid) should be used unless it is certain that the test strips will give a positive result with a particular peroxide-containing liquid [20],... 

Seliwanoff s test analy chem A color test helpful in the identification of ketoses, which develop a red color with resorcinol in hydrochloric acid. s3 liv3,nofs, test sellite liNORG chem A solution of sodium sulfite (Na2S03) used in the purification of 2,4,6-trinitrotoluene to remove unsymmetrical isomers. se,lTt ... 

There are a number of full-scale activated sludge plants that are in operation in countries such as the United States, Canada, and Finland, which treat effluents from Kraft, sulfite, TMP, CTMP, and newsprint mills [22]. SchneU et al. [70] reported the effectiveness of a conventional activated sludge process operating at an alkaline-peroxide mechanical pulping (APMP) plant at Malette Quebec, Canada. The full-scale plant achieved 74% reduction in filterable COD and nearly complete elimination of BOD5, resin acids, and fatty acids in the whole mill effluent. The treated effluent tested nontoxic as measured by a Microtox assay. Saunamaki [71] reported... 

An application in power production, particularly in coal-fired power plants, is the analysis of flue gas scrubbers which remove excess SO2 following coal combustion. Tests run by SAMBESRL at the EPA s Research Triangle Park facility (8,9) have demonstrated the effectiveness of IC in determining sulfite and sulfate in flue gas desulfurization systems. Table III gives results of direct IC analysis of scrubber liquors compared with turbidimetric and titration methods. 

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