The analysis and grading of creosotes . 200 ZIO ZZXf Z50 ZW 250 260 270 280° 230 500° JIG 320°3J0° JiOJSO° J60 TLMPEIRATURE Fig. 24.—Distillation limits for Grade B. pure coal-tar creosote; this oil does not consist of hydrocarbons andis soluble in caustic alkalies. The sulphuric acid should, therefore, bedrawn off, the oil washed with water, and a 10 per cent solutionof sodium hydroxide added. If the oil is soluble in this reagent, thesulphonation test is regarded as negative. [Cir. 112] 40 TAR ACIDS. Fifty cubic centimeters of the creosote under analysis are measuredat 60° into a small disti
The analysis and grading of creosotes . 200 ZIO ZZXf Z50 ZW 250 260 270 280° 230 500° JIG 320°3J0° JiOJSO° J60 TLMPEIRATURE Fig. 24.—Distillation limits for Grade B. pure coal-tar creosote; this oil does not consist of hydrocarbons andis soluble in caustic alkalies. The sulphuric acid should, therefore, bedrawn off, the oil washed with water, and a 10 per cent solutionof sodium hydroxide added. If the oil is soluble in this reagent, thesulphonation test is regarded as negative. [Cir. 112] 40 TAR ACIDS. Fifty cubic centimeters of the creosote under analysis are measuredat 60° into a small distilling flask by a pipette. The oil is distilledas completely as possible without breaking the distilling bulb, and the. f ^00° ZIO IZO 2J0 240 250 260 270 280 230 J00° J/O J20 JJO J^0° JSO J60° TEMPERATUREFig. 25.—Distillation limits for Grade C. distillate is caught in a short-stermned, 100 c. c. separating fun-nel. At the end of the distillation 25 c. c. of boiling hot 15 per centsodium hydroxide is added to the distillate and the mixture thor-oughly shaken. The alkaline extract is then drawn off into a100 c. c. shaking cylinder and 25 c. c. more of hot sodium hydrox- [Cir. 112] 41 ide added. After extracting with this second portion for fiveminutes, with frequent shaking, the sohitions are allowed to scpiuatcand the alkaline extract added to the first portion in the third extraction is made Avith 15 c. c. of alkali. The total alkalineextract is cooled, acidified with sulphuric acid, thoroniihly shaken,brought to 60°, and the volume of supernatant oil read off. WATER. After weighing the first two fractions of a fractional distillationthey are united in a small separatory funnel and
Size: 1461px × 1710px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bo, bookcentury1900, bookdecade1900, bookpublisherwashingtondcgpo
