Methyl chloride for industrial use — Determination of impurities — Gas chromatographic methods
Specifies a method, the principle of which is based on the analysis of a vaporzed test portion and determination of the contents of impurities. The calibration factors used for this determination are obtained by analysis of external methyl chloride calibration mixtures containing known quantities of the impurities under consederation.
Butadiene for industrial use — Determination of tert-butyl-catechol (TBC) (4- (1,1-dimethyl- ethyl)-...
TBC is added as an oxidation inhibitor to 1,3-butadiene for industrial use. For the determination the inhibitor is separated from the butadiene by evaporation. The residue is dissolved in water and an excess of iron(III) chloride is added. The spectrometric measurement of the absorbance of the yellow-coloured complex is carried out at a wavelength of about 425 nm. The method is applicable to…
Chemical products for industrial use — General method for determination of iron content — 1,10-Phena...
All the iron(III) present in the test solution is reduced to iron(II) with ascorbic acid. At a pH between 2 and 9 1,10-phenanthroline is added. the measurement of the absorbance of the orange-red complex formed is carried out at the wavelength of maximum absorption (510 nm). The method is applicable to test solutions from which an aliquot portion can be taken containing between 10 and 500 g of Fe…
Higher alcohols for industrial use — Methods of test — Part 7: Determination of distillation yield
Relates to C6 to C13 alcohols. The principle consists in distillation of a test portion, under carefull defined conditions. For measurement of distillation intervals not greater than 5 °C, the thermometer hsall be graduated at intervals of 0,2 °C; for intervals greater than 5 °C, the thermometer shall be graduated at intervals of 0,5 °C. Adjusting the rate of heating so that the first drop of…
