Nonvolatile matter

Impurities in bromine may be deterrnined quantitatively (54). Weighing the residue after evaporation of a bromine sample yields the total nonvolatile matter. After removing the bromine, chloride ion may be deterrnined by titration with mercuric nitrate, and iodide ion by titration with thiosulfate water and organic compounds may be detected by infrared spectroscopy sulfur may be deterrnined turbidimetricaHy as barium sulfate and heavy metals may be deterrnined colorimetricaHy after conversion to sulfides. 

In the manufacture of ethylene dibromide, gaseous ethylene is brought into contact with bromine by various methods, allowing for dissipation of the heat of reaction (100—102). Eree acids are neutralized and the product maybe fractionally distilled for purification. Typical specifications call for a clear Hquid with 99.5% purity min sp gr (25/25°C), 2.170—2.180 boiling range, 130.4—132.4°C APHA color, 200 max water, 200 ppm max acidity as HCl, 0.0004 wt % max and nonvolatile matter, 0.0050 wt % max. 

A cosmetics industry specification for /-butyl alcohol (31) is 99.5% alcohol, a maximum 0.002% acidity (as acetic acid), a maximum of 0.1% water, and a maximum of 0.001% nonvolatile matter. 

Apart from added stabilizers, commercial grades of trichloroethylene should not contain mote than the following amounts of impurities water 100 ppm acidity, ie, HCl, 5 ppm insoluble residue, 10 ppm. Free chlorine should not be detectable. Test methods have been estabUshed by ASTM to determine the following characteristics of trichloroethylene acid acceptance, acidity or alkalinity, color, corrosivity on metals, nonvolatile-matter content. 

ASTM has estabhshed standard test methods to determine acid acceptance, acidity, alkalinity, color, corrosivity to metals, nonvolatile matter content. 

The residue (ASTM D1025, D2158 IP 317) (i.e. nonvolatile matter) is a measure of the concentration of contaminants boiling above 37.8°C (100°F) that may be present in the gas. 

Nonvolatile Matter. Evaporate 100ml of the sample on a steam bath in a tared dish (preferably platinum) and dry the residue to constant weight in an oven, maintained at 105 to 110°C. The increase in weight of dish shall be calcd as percentage non-volatile residue. Calculate as follows ... 

Nonvolatile matter in g/lOOml = B—A where A tare wt of dish... 

Acrylonitrile of 99.5-99.7% purity is available commercially, with the following specifications (ppm by weight, maximum) acidity (as acetic acid), 10 acetone, 75 acetonitrile, 300 acrolein, 1 hydrogen cyanide, 5 total iron, 0.1 oxazole, 10 peroxides (as hydrogen peroxide), 0.2 water, 0.5% and nonvolatile matter, 100. Hydroquinone monomethyl ether (MEHQ) is added as an inhibitor at concentrations of 35-45 mg/kg (ppm) (Cytec Industries, 1994, 1997). Trade names for acrylonitrile include Acritet, Acrylon, Carbacryl, Fumigrain and Ventox. 

It is stated that protoxide of mercury ia occasionally adulterated -with minium or red lead, sesquioxide of iron, and powdered brick. Such substances are readily detected by heating the substance to a dull heat the protoxide of meroury sublimes, and leaves the nonvolatile matters in the crucible, or the mercurial compound maybe treated with dilute nitric add, to dissolve the mercurial oxide and should minium be present, a pace-colored binoxide of lead remains together with the other adulterants, if any be present. On adding dilute sulphuric acid to the door liquor obtained in the foregoing, a white precipitate of sulphate of lead falls, corroborative of the existence of a lead compound. 

The production of cocamidopropyl betaine has traditionally been based on two feedstocks coconut oil and topped or stripped (C-8 and 10 removed) coconut fatty acid or methyl ester. These products are still widely used but, to achieve better colors and odors, hydrogenated feedstocks are now very frequently used, either fully hydrogenated coconut oil triglyceride or stripped, hydrogenated, distilled coconut fatty acid. These products are most frequently sold as aqueous solutions with 35% nonvolatile matter. If made from triglyceride, the betaine surfactant will contain about 2.5% glycerin by-product and 5% sodium chloride by-product in addition to the active surfactant. Products made from fatty acid or methyl ester are approximately 30% active product and slightly more than 5% sodium chloride. 

Residue Not more than 0.015%, by weight, of nonvolatile matter. 

Hydrous lanolin Hydrous wool fat, Lipolan BP, JP, PhEur Melting range 38-44 °C acid value <0.8 saponification value 67-79 nonvolatile matter 72.5-77.5% iodine value 18-36 ... 

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