ASTM D5799 Standard Test Method for Determination of Peroxides in Butadiene
5. Apparatus
5.1 Condensers, Liebig, with 24/40 standard-tapered ground-glass joint connections.
5.2 Cylinders, graduated, 100-mL capacity.
5.3 Flask, Erlenmeyer, 250-mL capacity, with 24/40 standard-tapered ground-glass connections with marking at 100 mL.
5.4 Heating Mantle, electric for 250-mL Erlenmeyer flasks.
5.5 Microburette, 10-mL capacity, graduated in 0.02-mL divisions.
5.6 Water Bath, a thermostatically controlled liquid bath capable of maintaining a water temperature of 60 +/- 1°C (140 +/- 2°F).
6. Reagents
6.1 Purity of Reagents - Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all reagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society, where such specifications are available. Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purity to permit its use without lessening the accuracy of the determination.
6.2 Purity of Water - Unless otherwise indicated, references to water shall be understood to mean deionized or distilled water.
6.3 Acetic Acid, 94 % by volume. Mix 60 mL of water with 940 mL of glacial acetic acid (CH3COOH). (Warning - Poisonous and corrosive. Combustible. May be fatal if swallowed. Causes severe burns. Harmful if inhaled.)
6.4 Carbon Dioxide, solid (dry ice). (Warning - Use gloves to avoid frostbite when handling.)
6.5 Potassium Dichromate Solution, Standard (0.1 N) - Dissolve 2.452 g of potassium dichromate (K2Cr2O7) in water and dilute to 500 mL in a volumetric flask.(Warning - Avoid contact with eyes and skin and avoid breathing of dust.)
6.6 Sodium Fluoride.
6.7 Sodium Iodide.
6.8 Sodium Thiosulfate Solution, Standard (0.1 N) - Dissolve 12.5 g of sodium thiosulfate (Na2S2O3 x 5H2O) plus 0.1 g of sodium carbonate (Na2CO3) in 500 mL of water (the Na2CO3 is added to stabilize the Na2S2O3 solution). Let this solution stand a week or more before using. Standardize against 0.1 N K2Cr2O7 solution. Restandardize at frequencies to detect changes of 0.0005 in normality.
7. Sampling
7.1 Butadiene should be sampled in a metal container of a type which ensures maximum safety and which is resistant to butadiene corrosion. The size of the container is dependent upon the number of times the test is to be performed according to this test method. Refer to Practice D1265 or Practice D3700 for instructions on sampling.
