ISO 17315-2014 pdf free download

ISO 17315-2014 pdf free download.Petroleum products and other liquids — Ethanol — Determination of total acidity by potentiometric titration
Produits pétroliers ec autres liquides — Ethanol — Dosage de i’acidire to tale par titration poten tiorn étriq ue.
3.6 Sodium hydroxide solution (NaOH), 1,0 mol/l, a solution prepared in accordance with the following or a commercially available standardized sodium hydroxide solution of equivalent concentration.
— In order to prepare NaOH, 1,0 mol/l, weigh in a beaker (40,0 ± 0,1) g of sodium hydroxide, dissolve
with 200 ml of water (3.1) and stir until complete dissolution, and homogenize. Transfer to a
volumetric flask of 1 000 ml and complete the volume with water (3.1). Stock the solution in a
polyethylene flask and keep at a temperature below 25 °C.
— This solution has a 2 mo shelf life.
3.7 Sodium hydroxide solution (NaOH), 0,02 rnol/l, a solution prepared in accordance with IL! or a commercially available standardized sodium hydroxide solution of equivalent concentration.
3.7.1 In order to prepare NaOH, 0,02 mol/l, transfer to a 500 ml volumetric flask (10,0 ± 0,1) ml of sodium hydroxide solution, 1,0 mol/l, and complete the volume with water (11) and homogenize. Stock the solution in a polyethylene flask and keep at a temperature below 25 °C. The reagent shall be restandardized frequently enough to detect concentration changes. The solution shall be protected against carbon dioxide absorption. The solution has a 15 d shelf life.
3.7.2 Determine the actual molar concentration of sodium hydroxide solution (3.Zd) as follows.
a) Dry the potassium hydrogen phthalate (32) in a drying oven at (120 ± 5) °C for a minimum of 2 h and store in a desiccator.
b) In a beaker, weigh approximately 100 mg of potassium hydrogen phthalate [(3.7.2 a)J and record the mass value.
c) Add 100 ml of water (11) and stir until complete dissolution.
d) Start the procedure as follows if the solution and the apparatus system are at a temperature around 20 to 25 °C.
e) Carry out a potentiometric titration with the sodium hydroxide solution 0,02 mol/I (17.1) until the equivalency point using the apparatus described in Clause 4. and after checking the apparatus calibration according CLau..
1) Using 100 ml of water (3.1), carry out a blank potentiometric titration with the sodium hydroxide solution 0,02 mol/l (32.1) until the equivalency point using the apparatus described in Clause 4.
g) Calculate molar concentration of the solution using Formula (1):ISO 17315-2014 pdf free download.