BS ISO 6495-1 pdf free download

BS ISO 6495-1:2015 pdf free download.Animal feeding stuffs一 Determination of water-soluble chlorides content Part 1: Titrimetric method.
6 Sampling
Sampling is not part of the method specified in this part of ISO 6495. A recommended sampling method is given in ISO 6497.
It is important that the laboratory received a sample which is truly representative and has not been damaged or changed during transport or storage.
7 Preparation of test sample
Prepare the test sample in accordance with ISO 6498.
If solid, grind a representative part, 100 g to 150 g of the laboratory sample (usually 500 g) so that it
passes completely through a sieve with 1 mm apertures. Mix thoroughly.
8 Procedure
8.1 Preparation of test solution
8.1.1 General
If the test sample is free from organic matter, proceed in accordance with &L2.
If the test sample contains organic matter, proceed in accordance with 8.1.3.. unless the test sample concerns cooked feeding stuffs, flax cakes and flour, products rich in flax flour, and other products rich in mucilage or in colloidal substances (e.g. dextrinated starch). In this case proceed in accordance with 8.1.4.
8.1.2 Preparation of test solution of sample free from organic matter
Accurately weigh, to 0,000 1 g, not more than 10 g of the test sample (Clausel) containing not more than 3 g of chloride. Transfer to a 500 ml volumetric flask (5.2) and add about 400 ml of water (4.1) at a temperature of approximately 20 °C.
Mix for 30 mm in the rotary shaker (5.1), dilute to the mark with water (4.1), then mix, and filter through the filter paper (5.f).
Proceed in accordance with 82.
8.1.3 Preparation of test solution of sample containing organic matter, excluding the products listed in 8.1.4
Accurately weigh, to 0,000 1 g, approximately 5 g of the test sample (Clause 7) containing not more than 3 g of chloride. Transfer to a 500 ml volumetric flask (52). Add 1 g of activated carbon (4), about 400 ml of water (4.1) at a temperature of approximately 20 °C, and 5 ml of Carrez 1 solution (49). Then mix and add 5 ml of Carrez II solution 4JQ).
Mix for 30 mm on the rotary shaker (5.1). Dilute to the mark with water (4.1), then mix and filter through the filter paper (5.fi).
Proceed in accordance with 82.
8.1.4 Cooked feeding stuffs, flax cakes and flour, products rich in flax flour, and other products rich in mucilage or in colloidal substances
Accurately weigh, to 0,000 1 g, approximately 5 g of the test sample (Clause 7) containing not more than 3 g of chloride. Transfer to a 500 ml volumetric flask (52). Add 1 g of activated carbon (4.8). about 400 ml of water (4.1) at a temperature of approximately 20 °C, and 5 ml of Carrez I solution (4.9). Then mix and add 5 ml of Carrez II solution (4,j.Q).
Mix for 30 mm on the rotary shaker (5.1). Dilute to the mark with water (4.1), then mix.
Decant (if necessary, centrifuge). By means of a pipette (5.3), transfer 100 ml of the supernatant to a 200 ml volumetric flask (52).
Dilute to the mark with acetone (42), then mix, bring the volume to the mark with acetone or water, remix and filter through the filter paper(5.6).
Proceed in accordance with 82.
8.2 Titration
By means of a pipette (5.3), transfer to a conical flask an aliquot portion of between 25 ml and 100 ml (Va) of the filtrate. The aliquot portion shall not contain more than 150 mg of chloride.
Dilute, if necessary, to a volume of not more than 100 ml with water. Add 5 ml of dilute nitric acid (4.5), 2 ml of saturated ammonium iron(lll) sulfate solution (4.7) and 2 drops of standard ammonium or potassium thiocyanate solution (4.13) from a burette (5.4) filled to the zero mark.
Add standard silver nitrate solution (412) from another burette (5.4), while shaking until the reddish brown tint disappears, then add an excess of 5 ml standard silver nitrate solution (total volume of AgNO3 = V51). Shake vigorously to coagulate the precipitate. If necessary, 5 ml of n-hexane (4.3) may be added to assist coagulation.
Titrate the excess standard silver nitrate solution (4.12) with standard ammonium or potassium thiocyanate solution (4.13) from the burette until a reddish brown tint persists for at least 30 s (total volume of including 2 drops = V1).
8.3 Blank test
Carry out a blank test in parallel with the determination, using the same procedure and the same reagents, but omitting the test portion.BS ISO 6495-1 pdf download.