BS EN ISO 27587:2021 pdf free
BS EN ISO 27587:2021 pdf free.Leather—Chemical tests—Determination of free formaldehyde in process auxiliaries.
This document specifies a method for the determination of free formaldehyde, which is released under dynamic conditions when the sample is heated in an inert dry atmosphere, in process auxiliaries for leather. The analytical result obtained according to this procedure is expressed in milligrams per kilogram (mg/kg) sample.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements 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.
ISO 3696, Water for analytical laboratory use — Specification and test methods
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/
4 Principle
The sample is heated in an inert atmosphere for a defined period of time. The released formaldehyde is captured and derivatized using a dinitrophenylhydrazine (DNPH) cartridge. The analyte is eluted with acetonitrile and analysed by high-performance liquid chromatography (HPLC) using an ultraviolet (UV) or diode array detector (DAD).
S Reagents
Use only reagents of recognized analytical grade, unless otherwise stated.
5.7 Calibration standards. Prepare solutions by adequate dilution of the formaldehyde-2,4-DNPH
analytical standard (Sb).
5.8 Formaldehyde solution, a mass fraction of approximately 37 %.
5.9 Distilled water, quality 2 in accordance with ISO 3696.
5.10 Formaldehyde solution Si. prepare by pipetting 5 ml of formaldehyde solution (5k) in a 1 000 ml volumetric flask and filling to the mark with distilled water.
5.11 Formaldehyde solution S2 in an adequate dilution for procedure control Ie.g. 2,5 ml of the formaldehyde solution Si (S1U) in a 100 ml volumetric flask, fill up with distilled water. The concentration of this solution should be adapted to ensure that the formaldehyde content is in the middle of the calibrated range.j
5.12 2,4-Dinitrophenylhydrazine cartridges (DNPH cartridges), suitable for fixing a total of 6 400 .*g
of carbonyls per cartridge.
For lower quantities of free formaldehyde, a smaller capacity cartridge can be used.
For higher quantities of free formaldehyde, increase the number of cartridges to be loaded in series.
It is recommended that the cartridge has an excess capacity of at least 20 % more than the predicted formaldehyde amount.
5.13 Acetonitrile, [IPLC grade.
5.14 Water, I-IPLC grade.
6 Apparatus and materials
The usual laboratory apparatus is required and, in particular, the following.
6.1 Thermostatic oil bath with stirring facilities, capable of maintaining a constant temperature of (90 ± 3) °C. The oil bath shall be deep enough to allow the U-tube to be dipped in up to the side tubing.
6.2 Silicone oil, suitable for oil bath (bJ).
6.3 Nitrogen, purity 4,6.BS EN ISO 27587 pdf free download.
