Titanous chloride standard solution

Standardization of0.2N Titanous Chloride Solution. Sweep the air from a 300-ml reduction flask with a current of nitrogen or carbon dioxide gas for 5 mins. Continue to pass the current of gas thru the flask until the titration is completed... 

STD-286B (1 Dec 1967), Method 601.1.1, "Titanous Chloride (0.2N Standard Solution) 20) Frank pristera , 1 Expiosives in Vol 12 of Encyclopedia of Industrial Chemical Analysis, Wiley, NY (1971), pp443—45 (Nitroglycerin and Dynamites, Analysis) 445 (PETN) 445 fit 451 (Ethyleneglycol Nitrates) - 451 (Other organic nitrate esters) 451 (Ammonium Nitrate) 452—60 (Identification of explosives by infrared spectroscopy) 460—62 (Analysis of unknown HE s) 461—67 (Nitrogen content determinations) 467—70 (Other methods for quality control) 470—71 (67 references on analytical procedures)... 

A further method consists in treating a solution of chromate udth an excess of methylene white (the leuco base of methylene blue) in presence of hydrochloric acid. The methylene blue produced is then titrated with standard titanous chloride, the temperature being kept above 40° C. in order to sharpen the end-point. The whole process should be performed in an atmosphere of carbon dioxide. In applying this method to ferrochrome or chromium steel, the iron and chromium may be estimated together, the iron then being determined separately by ordinary methods and the chromium obtained by difference. The reaction may also be used colorimetrieally. ... 

Titration. After cooling, 10 ml water and 1 ml potassium thiocyanate (20%) are added. The titration with titanous chloride is carried out in the digestion tube in a COa atmosphere. The titanous chloride solution (about 0.15%) is frequently standardized against the ferric ammonium sulfate stock solution (mentioned in Section 2.1.2). 

To the sample solution, in a 25-ml standard flask, containing not more than 12 pg of Mg, add 1 ml of the calcium chloride solution, 2.5 ml of the Titan Yellow solution, 3 ml of 1% polyfvinyl alcohol) solution, and water to 17 ml. While swirling the solution vigorously, add 1 M NaOH dropwise from a burette until the solution changes colour. Then add 2.5 ml more NaOH solution with continued mixing, and dilute the solution with water to the mark. After 15 min, measure the absorbance of the solution at 545 nm against a blank solution containing the same amount of calcium. 

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