BS 551:1990 pdf free.Specification for Butyl acetate forindustrial use.
BS 551 A test portion is diluted with 95 % (VIV)ethanol volumetric sodium hydroxide solution,usingauphenolphthalein as indicator. During the analysis,use only reagents of recognizedanalytical grade, only methylated spirits complyingwith BS 3591, and only water complying with grade 3 of BS 3978.
Ethanol or industrial methylatedspirits,95 %(VIV). NOTE The use of industrial methylated spirits is governed by The Methylated Spirits Regulations,1983 (S.1. 1983 No.252).itis not permissible to use duty-free ethanol, received under the provisions of The Alcoholic Liquor Duties Act 1979, Section 10,for purposes for which industrial methylated spirits is an acceptable alternative.
Sodium hydroxide, standard volumetricsolution,c(NaOH)= 0.100 mol/L.
Phenolphthalein, 5 g/L ethanolic solution.Dissolve 0.5 g of phenolphthalein in 100 mL of the ethanol or industrial methylated spirits (B.2.2) andadd the sodium hydroxide solution (B.2.3) until a pale pink coloration is obtained.Conical flask, of 250 mL capacity, of borosilicate glass, fitted with a ground glass stoppercarrying a guard tube containing sodium hydroxideon an inert support (soda lime).Attach a reflux condenser to each conical flask andheat the two flasks for 1 h in a boiling-water bath.Withdraw the flasks, still carrying their condensers,and immerse them in cold running water. Whencool, wash down the inside of each condenser withtwo 20 mL portions of water, collecting the
washings in the flask. Disconnect the flasks andwash each joint with a further 20 mL of water,again collecting the washings in the appropriateflask. Add 0.5 mL of the phenolphthalein solution (C.2.4)to each flask and immediately titrate the contents ofeach flask in turn with the hydrochloric acid solution (C.2.3) until the pink colour is justdischarged.
The esters present in a test portion are saponifiedwith excess ethanolic potassium hydroxide solutionand the excess is determined by titration with
standard volumetric hydrochloric acid solution,using phenolphthalein as indicator.
During the analysis, use only reagents of recognizedanalytical grade, only methylated spirits complyingwith BS 3591, and only water complying with grade 3 of BS 3978.BS 551 pdf download.