BS EN 241 pdf free download
BS EN 241 pdf free download.Methods of test for petroleum and its products一 BS 2000-464: Liquid petroleum products.
4 Reagents and materials Use only reagents of recognized analytical grade and water conforming to grade 3 of EN ISO 3696. 4.1 Hydrochloric acid, c(HCI) = approximately 1 mol/I. 4.2 Hydrofluoric acid, 38 % (rn/rn) to 40 % (rn/rn), sodium free. WARNING Great care shall be taken in the handling of hydrofluoric acid as it causes severe burns and permanent injury. Consult the manufacturer’s handling instructions. Gloves and eye- protection shall be worn when handling the acid solutions. If the acid does come in contact with the skin, wash the affected area with a continuous stream of water and seek immediate medical assistance. 4.3 Sulfuric acid, 10 % (rn/rn), sodium free. 4.4 Air, oil free, under pressure in a steel cylinder or pipe. 4.5 Acetylene, under pressure in a steel cylinder or pipe. 4.6 Aqueous standard sodium solution, c(Na) = 0,1 g/l (w(Na)=100 mg/kg). Either: a) dry sodium chloride for at least 10 h at (105 ± 5) °C and store it in a desiccator. Dissolve (2,543 ± 0,00 1) g of the dried sodium chloride in water in a 1 000 ml volumetric flask (5.5) and make up to the mark. Transfer 10 ml of this solution into a 100 ml volumetric flask (5.5), add 1 ml of hydrochloric acid (4.1) and make up to the mark with water; or; b) transfer 434,8 ml of a sodium chloride solution, c(NaCI) = 0,01 mol/l, into a 1 000 ml volumetric flask (5.5), add 10 ml of the hydrochloric acid (4.1) and make up to the mark with water; or; c) as an alternative, commercially available and certified standards may also be used. 4.7 Blank solution, water (see clause 4), to which 1 ml of the hydrochloric acid (4.1) per 100 ml water has been added. 5 Apparatus Usual laboratory apparatus and glassware, together with the following: 5.1 Flame atomic absorption spectrometer, suitable for measurements at a wavelength of 589,0 nm, and fitted with a burner feed for acetylene and air. 5.3 Incineration vessel, either a platinum crucible， capacity approximately 50 mI, diameter approximately 35 mm, or a platinum dish, capacity approximately 130 ml, diameter approximately 75 mm, freed from sodium by rinsing with the hydrochloric acid (4.1). 5.4 Muffle furnace， electrically heated and capable of maintaining a temperature of (550土25) °C. 5.5 One-mark volumetric flasks, capacity 50 ml, 100 ml, 250 ml and 1 000 ml, conforming to class A of ISO 1042. 5.6 Polyethene bottles, for storage of the calibration solutions. 5.7 Burette, capacity 50 mI, graduated in 0,1 ml, conforming to class A of ISO 385-1. Automatic burettes of pipettes may be used, provided that they meet the same requirements. 6 Sampling Unless otherwise specified in the commodity specification, samples shall be taken as described in EN . ISO 3170 or EN ISO 3171, and/or in accordance with the requirements of national standards or regulations for the sampling of the product under test. Prepare test samples by pouring a suitable quantity of sample into clean containers of glass, polypropene (PP) or polytetrafluoroethene (PTFE) that have been freed from sodium by rinsing twice with the hydrochloric acid (4. 1), rinsed with water and dried.7 Procedure 7.1 Preparation of the calibration graph 7.1.1 Preparation of a set of calibration solutions Prepare a set of calibration solutions with a sodium content as given in table 1 as follows. Using a burette (5.7), transfer volumes of the standard sodium solution (4.6) as given in table 1 into a series of eight one-mark 250 ml volumetric flasks (5.5). Make each up to the mark with water and mix well. Transfer to polyethene bottles (5.6) for storage. The prepared calibration solutions are stable for a maximum of 8 weeks and shall not be used for longer periods. BS EN 241 pdf download.
