EN ISO 8892:1995

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Ölsaatrückstände (Extraktionsschrot) - Bestimmung des gesamten Resthexans (ISO 8892:1987)Tourteaux de graines oléagineuses - Dosage de l'hexane résiduaire total (ISO 8892:1987)Oilseed residues - Determination of total residual hexane (ISO 8892:1987)67.200.20OljniceOilseedsICS:Ta slovenski standard je istoveten z:EN ISO 8892:1995SIST EN ISO 8892:1998en01-november-1998SIST EN ISO 8892:1998SLOVENSKI
STANDARD



SIST EN ISO 8892:1998



SIST EN ISO 8892:1998



SIST EN ISO 8892:1998



INTERNATIONAL STANDARD 8892 INTERNATIONAL ORGANIZATIQN FOR STANDARDIZATION ORGANISATION INTERNATIONALE DE NORMALISATION MEXAYHAPO~HAIJ OPrAHM3A~MR RO CTAHflAPTM3A~MM I Oilseed residues - Determination of total residual hexane Tourteaux de graines o&agineuses - Dosage de l’hexane rtkiduaire total IS0 First edition 1987-06-01 Reference number IS0 8892 : 1987 (E) SIST EN ISO 8892:1998



Foreword IS0 (the International Organization for Standardization) is a worldwide federation of national standards bodies (IS0 member bodies). The work of preparing International Standards is normally carried out through IS0 technical committees. Each member body interested in a subject-for which a technical committee has been established has the right to be represented on that committee. International organizations, govern- mental and non-governmental, in liaison with ISO, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the IS0 Council. They are approved in accordance with IS0 procedures requiring at least 75 % approval by the member bodies voting. International Standard IS0 8892 was prepared by Technical Committee ISO/TC 34, Agricultural food products. Users should note that all International Standards undergo revision from time to time and that any reference made herein to any other International Standard implies its latest edition, unless otherwise stated. International Organization for Standardization, 1987 Printed in Switzerland SIST EN ISO 8892:1998



INTERNATIONAL STANDARD IS0 8892 : 1987 (E) Oilseed residues - Determination of total residual hexane 1 Scope and field of application This International Standard specifies a method for the deter- mination of the total amount of volatile hydrocarbons, referred to generally as hexane, remaining in oilseed residues after extraction with hydrocarbon-based solvents. 2 Reference IS0 5500, Oilseed residues - Sampling. 3 Principle Desorption of hexane by heating at 110 OC with water in a closed vessel, and determination of the hexane in the headspace by gas chromatography using capillary or packed columns. Expression of the results as n-hexane. 4 Reagents and materials 4.1 Technical n-hexane or light petroleum, with a com- position similar to that used in the industrial extraction of oilseeds, or failing that, n-hexane. 4.2 Carrier gas : hydrogen or nitrogen, helium, etc., dry and containing less than 10 mg/kg of oxygen. 4.3 Auxiliary gases : - Hydrogen, 99,9 % pure, containing no organic im- purities. - Air, containing no organic impurities. 5 Apparatus Usual laboratory apparatus and in particular 5.1 Gas chromatograph, with flame ionization detector and integrator and/or recorder, equipped with a glass capillary col- umn approrimately 30 m long and 0,3 mm in diameter, coated with methylpolysiloxanes l) (film thickness 0,2 pm) or, failing this, a packed column at least I,7 m long and 2 to 4 mm inter- nal diameter, packed with acid-washed diatomaceous earth of particle size 150 to 180 pm *j, and coated with methylpolysilox- anes I). If a capillary column is used, the apparatus shall have a 1 /IO0 input divider. 5.2 Electric oven, capable of being maintained at 110 OC. 5.3 Gas syringe, graduated, of capacity 1 ml, preferably with a valve. 5.4 Penicillin-type flasks, of capacity 50 to 60 ml, all with the same volume to within 2 %. 5.5 Septa, inert to solvents, of approximately 3 mm thickness, of a material such as nitrile rubber (for example Perbunan), or butyl rubber with a PTFE or polychloroprene seam (for example Neoprene). NOTE - Ensure that the septa used will produce a hermetic seal after crimping. 5.6 Metallic foil caps, for example of aluminium. 5.7 Crimping pliers. 5.8 liquid syringe, of capacity 10 ~1. 6 Sampling and sample storage See IS0 5500. It is essential that loss of hexane from the sam- ple be prevented. ’ The laboratory sample shall fill a compl.etely sealed container (preferably a crimped metal box) and shall be stored at - 20 OC or below (for example in a deep-freezer). Plastics containers shall not be used. The determination of residual hexane shall be carried out as soon as the container has been brought to room temperature and opened. 1) SE 30 is suitable. 2) Chromosorb WAW is suitable. SIST EN ISO 8892:1998



IS0 8892 : 1987 (E)
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