EN 15769:2009 – Ethanol as a blending component of petrol – Determination of appearance – Visual method
1 Scope
This European Standard specifies a procedure for the determination of appearance of ethanol by visual method. The method enables to determine colour and limpidity of ethanol.
NOTE Automotive fuel standards require a fuel to be clear and bright, meaning absent of particles, respectively absent of haziness. For this document that requirement is combined into a limpidity requirement.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
EN ISO 3696, Water for analytical laboratory use — Specification and test methods (ISO 3696:1987)
3 Terms and definitions
For the purposes of this European Standard, the following terms and definitions apply.
3.1
turbidity
degree of opacity of a fluid
3.2
limpidity
clarity
absence of turbidity
4 Principle
The absence of colour and the limpidity (effectively the absence of turbidity) are assessed visually by comparison with water against a white background and a black background.
5 Apparatus
5.1 Glass cylinders, colourless, 40 cm to 60 cm in height and 20 mm to 40 mm in diameter.
NOTE 1 Tubes used for alcohol measurement with an alcoholmeter may be used.
NOTE 2 To check that the base of the glass cylinder is clean and colourless, one can place them empty on the white background (5.3).
5.2 Water, for analytical laboratory use, conforming to grade 3 of EN ISO 3696
5.3 Background, white, respectively black paper sheet.
NOTE Paper of A4-size for laser printer application is sufficient.
6 Sampling
Collect the sample (500 ml) in glass bottles, Teflon or silicon capped.
Samples are stored at room temperature without any direct sun light prior to analysis.
7 Procedure
Fill one cylinder (5.1) with sample to a depth of approximately 40 cm and a second, comparison cylinder, with water (5.2) to the same height.
Place the two glass cylinders on the white background (5.3) for determination of the colour and the limpidity.
Observe the sample in a clear, well lighted room from above, i.e. through the length of the cylinder, and compare it with the comparison cylinder.
Repeat the observation on the black background.
8 Interpretation
Assess the colour and limpidity of the sample when observed as set out in Clause 7.
Determine visually, by comparison with the cylinder filled with water using both backgrounds, if the sample is coloured or colourless like the water is.
Determine visually, by comparison with the cylinder filled with water using both backgrounds, if the sample is turbid or clear like the water is.
EN 15769:2009 – Ethanol as a blending component of petrol – Determination of appearance – Visual method