ASTM D129 for sulfur in petroleum products (General Bomb method)
4. Apparatus and Materials
4.1 Bomb, having a capacity of not less than 300 mL, so constructed that it will not leak during the test and that quantitative recovery of the liquids from the bomb may be achieved readily. The inner surface of the bomb may be made of stainless steel or any other material that will not be affected by the combustion process or products. Materials used in the bomb assembly, such as the head gasket and lead-wire insulation, shall be resistant to heat and chemical action, and shall not undergo any reaction that will affect the sulfur content of the liquid in the bomb.
4.2 Sample Cup, platinum, 24 mm in outside diameter at the bottom, 27 mm in outside diameter at the top, 12 mm in height outside, and weighing 10 to 11 g.
4.3 Firing Wire, platinum, No. 26 B & S gage, 0.41 mm (16 thou), 27 SWG, or equivalent. (Warning - The switch in the ignition circuit shall be of a type which remains open, except when held in closed position by the operator.)
4.4 Ignition Circuit, capable of supplying sufficient current to ignite the cotton wicking or nylon thread without melting the wire. The current shall be drawn from a step-down transformer or from a suitable battery.
4.5 Cotton Wicking or Nylon Sewing Thread, white.
5. Reagents and Materials
5.1 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.
5.2 Purity of Water - Unless otherwise indicated, references to water shall mean water as defined by Type II or III of Specification D1193.
5.3 Barium Chloride Solution (85 g/litre) - Dissolve 100 g of barium chloride dihydrate (BaCl2•2H2O) in distilled water and dilute to 1 liter.
5.4 Bromine Water (saturated).
5.5 Hydrochloric Acid (sp gr 1.19) - Concentrated hydrochloric acid (HCl).
5.6 Oxygen, free of combustible material and sulfur compounds, available at a pressure of 41 kgf/cm 2 (40 atm).
5.7 Sodium Carbonate Solution (50 g/litre) - Dissolve 135 g of sodium carbonate decahydrate (Na2CO3•10H2O) or its equivalent weight in distilled water and dilute to 1 litre.
5.8 White Oil, USP, or Liquid Parafffin, BP, or equivalent.
5.9 Quality Control (QC) Samples, preferably are portions of one or more liquid petroleum materials that are stable and representative of the samples of interest. These QC samples can be used to check the validity of the testing process as described in Section 10.
