Sulfur acid salts

L. C. Schroeder, Sulfurous acid salts as pharmaceutical anti-oxidants, J. Pharm. Sci., 50, 891-901 (1961). 

Interesting data were reported in Reference 98 on the transformation of the sulfuric acid salt of amine under conditions of nitrosation (Scheme 3.37). 

Tests were also run with simulated brackish agricultural drainage water, as illustrated in Table 4. A feedwater composition containing sodium, calcium, chloride, sulfate, and bicarbonate ions was prepared in such a way as to duplicate the water in the Mohawk-Wellton drainage canal at Yuma, Arizona. Salt rejections were relatively poor toward this synthetic feedwater, but when this water was line-softened and acidified to pH 5.5 with sulfuric acid, salt rejection of the 90 10 copolyamide improved markedly. However, the membrane s water flux declined by nearly 50 percent. Salt rejection and flux were found in this and other examples to be markedly dependent on pH. As the pH approached the pKa of... 

Explosion of TNT Plant at Saint Chomas, France. A detailed description and analysis of the causes of an expln on 16-Nov 193(5 which.caused the death of 53 persons are reported. Pb Fe were found to produce expl substances from TNT in the presence of nitric acid which could be ignited by heat, shock, friction, or contact with coned nitric sulfuric acids. Salts of Pb Fe were found at the scene of the expln Ref A- Kovache H. Thibon, MP 34, 369-88(.1952) CA 49, 4293(1955)... 

F. 1,4,7,10,13,16-Hexaazacyclooctadecane (6). A 3-1., threenecked, round-bottomed flask is equipped with mechanical stirrer, nitrogen inlet, and addition funnel. In the flask are placed 200 g. (0.169 mole) of cyclic hexamine 5 and 500 ml. of concentrated (97%) sulfuric acid. The stirred mixture is held at 100° for 70 hours and then cooled in ice as 1300 ml. of anhydrous ethyl ether is slowly added. The precipitated polyhydrosulfate salt is filtered under nitrogen and washed with anhydrous ethyl ether (Note 7). The salt is then stirred in 200 ml. of water and cooled in ice as 71 ml. of aqueous 50% NaOH is added to neutralize the solution. Three grams of activated carbon are added, and the solution is heated to 80° and filtered through Celite. The filtrate is cooled in ice and reacidified to pH 1 by adding 42 ml. of concentrated sulfuric acid. The white, non hygroscopic tris(sulfuric acid) salt of 6 that precipitates is collected and washed with 95% ethanol. 

The sulfuric acid salt of 5 (Parnate Jatrosom ) is used as an antidepressant drug, and best results were achieved in chronic neurotic patients. (+ )-(5) was reported to be also effective as an adjuvant in Parkinson s disease therapy . Differences of activities of the pure enantiomers (for a minireview see Ref. 629 for resolution of racemic 5 see Refs 42, 103, 160, 654, 655 for g.c. separation of racemic 5 as iV-trifluoracetyl-L-prolyl derivative, see Ref. 656) and the trans-cis diastereomers 5/628 have been studied as well as the selectivities of 5 on inhibition of MAO type A and B (e.g. Refs 637, 638, 658-674). (+ )-(5) showed stronger inhibition of platelet (dopamine ... 

Schroeter LC. Oxidation of sulfurous acid salts in pharmaceutical systems. / Pharm Set 1963 52 888-892. 

Scheme 124 Preparation of methyl methoxy carbamoyl chloride from the sulfuric acid salt of methoxy methyl amine.

Wang, M. L., Hu, K. H. (1994). Extraction of phenol using sulfuric acid salts of trioctylamine in a supported hquid membrane. Industrial and Engineering Chemistry Research 33 914-921. 

The protonated oxygens cause an expected lengthening of the C-0 bonds from 1.22A (avg) in the neutral compound to 1.30A (avg) in the sulfuric acid salt. In addition the C-N amide bond is shortened from 1.36A (avg) to 1.30A (avg), indicating a substantial increase of double bond character in this bond. 

E223 Sodium bisulfite Sulfurous acid salt Antioxidant, preservative Allergic and skin reactions 0-0.7 Frozen prawns, potatoes, alcoholic drinks, pickles, orange juice... 

Sulfuric acid is one of the most traditional antimicrobial substances, widely employed in products such as wines. It is soluble in water and gives sulfurous acid and its ions when it comes into contact with water in foods. The ions percentage increases with the reduction of pH value. Sulfuric acid salts can be used as preservatives and are more useful since they are available in dry forms. The antimicrobial action against yeasts and moulds and bacteria is selective, with certain species to be more sensitive in inhibition compared to other species. Bacteria are generally more sensitive in inhibition. Sulfur dioxide and sulfuric acid salts are GRAS substances however, their level of use in wines is restricted to 0.035%. Its presence at higher levels lead to undesired taste and is generally forbidden in foodstuffs that are considered as sources of thiamine due to the fact that they inactivate... 

Lepomis macrochirus Bluegill EW 51,200 3200 Sulfuric acid, salt 96 h... 

Schroeter, L. C. (1963) Kinetics of air oxidation of sulfurous acid salts. Journal of Pharmaceutical Science 52, 559-563... 

Wet spinning Spinning of a viscous fluid into a liquid bath (e.g., xanthate solution into sulfuric acid, salt-hydrate cellulose melt into ethanol)... 

The essence of the purification method used in the production of diamond nanopowders is to dissolve impurities of metals and their compounds and oxidize nondiamond forms of carbon by chromic anhydride in the presence of sulfuric acid. The use of such a strong oxidant in the presence of a strong acid makes it possible to combine in one stage the purification of diamonds both from nondiamond carbon forms and from metal impurities. The suspension of the nanodiamond-containing mixture is filtered through a set of sieves to remove mechanical impurities, the metal part is removed by magnetic treatment, and the solid phase is concentrated by nutsch filters. Dissolution of impurities of metals and their compounds and oxidation of nondiamond forms of carbon is carried out in a reactor (further on, this operation is called oxidation ). One run of oxidation to purify 3.3-3.7-kg solid phase of the mixture requires 24-27-kg sulfuric acid and 6.9-7.5-kg chromic anhydride. In the oxidation, when a solution of chromic anhydride is added, the temperature in the reactor reaches 125-130°C the mixture is kept in the reactor with sulfuric acid and chromic anhydride for 3-4 h. Following the oxidation, the reaction mixture is washed with water to remove chromium and sulfuric-acid salts. The yield is a nanodiamond suspension that contains 2.3-2.5-kg solid phase. 

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