Halogens determination

After preparing the tube carry out the combustion of the substance exactly as is described in detail for the halogen determination. Since complete absorption of sulphur trioxide by the absorbent requires a long period of contact, employ a slower current of oxygen (3-4 c.c. per minute) and, correspondingly, move the Bunsen burner forward more slowly. The combustion of the substance should require about one hour. 

After the combustion is finished wash out the tube as described for the halogen determination, collecting the liquid in a small clean beaker and add the contents of the test tube, washing it out also. Then add a clear filtered mixture of 2-3-5 c.c. of barium chloride solution (1 10) and 10 drops of dilute hydrochloric acid, cover with a clean watch-glass, heat to boiling, and continue until separation of barium sulphate ceases. Immerse the beaker in cold water to cool and complete the determination as described in the preceding section. 

Halogens, determinations of, 75. Heating under pressure, 58. Helianthine, 229. 

Generators, used oil collection centers, and aggregation points are not required to maintain records of the total halogen determination. However, if a subsequent used oil handler needs to rebut the presumption, it may be difficrdt to do without obtaining certain information from the generator. 

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