Butane-1,4-diol for industrial use — Determination of degree of unsaturation
A test portion is treated with a solution of bromine in absolute methanol saturated with sodium bromide (Kaufman solution). After addition of potassium iodide solution the liberated iodine is titrated with standard volumetric sodium thiosulfate solution. The degree of unsaturation is expressed as iodine value, the number of grams of iodine absorbed by 100 g of a substance under specified…
Industrial wire screens and woven wire cloth — Guide to the choice of aperture size and wire diamete...
Tabulates values which are taken from the general list of combinations given in ISO 4783/1. Applies to aperture sizes from 125 to 1 mm. The screens shall de designated in the following sequence by a) width of aperture, b) diameter of wire, c) material of wire, d) type.
Acetic acid for industrial use — Methods of test — Part 4: Determination of acetaldehyde monomer con...
The principle of the determination consists in reaction of the acetaldehyde present in a test portion with an excess of sodium hydrogen sulphite solution, and iodometric titration of the residual sodium hydrogen sulphite. The method is applicable to products having acetaldehyde monomer contents equal to or greater than 0,01 % (m/m). This International Standard as also been approved by the…
Acetic acid for industrial use — Methods of test — Part 5: Determination of total acetaldehyde conte...
The method specified consists in heating a test portion in an acid medium to depolymerize any to paraldehyde present and to entrain, by distillation, both regenerated acetaldehyde and the monomeric acetaldehyde originally present. Reaction of the acetaldehyde in the distillate with an excess of sodium hydrogen sulphite solution. Iodometric titration of the residual sodium hydrogen sulphite…
Acetic acid for industrial use — Methods of test — Part 6: Determination of permanganate index
The principle consists in reaction of a test portion, under specified conditions, with an excess of potassium permanganate solution in the presence of dilute sulphuric acid. Iodometric titration of the residual potassium permanganate. The method is applicable to products having permanganate indexes equal to or greater than 10 mg/100 ml. It has also been approved by the International Union of Pure…
Acetic acid for industrial use — Methods of test — Part 7: Determination of dichromate index
The principle consists in heating a test portion with an excess of potassium dichromate solution in the presence of sulphuric acid. Iodometric titration of the residual potassium dichromate. The method is applicable to products having dichromate inexes equal to or greater than 0,04 ml. It has also been approved by the International Union of Pure and Applied Chemistry (IUPAC). ISO 753/1 to ISO 753…
Acetic acid for industrial use — Methods of test — Part 8: Visual limit test for inorganic chlorides
Specifies a method for a visual comparison of the tubitity obtained by adding a silver nitrate solution to a solution of a test portion acidified with nitric acid, with that similary obtained from a chloride solution of known concentration. Using a test portion of 50 g, the method is applicable directly to products having inorganic chloride contents in the range 0,0005 % (m/m) to 0,05 % (m/m).…
Acetic acid for industrial use — Methods of test — Part 9: Visual limit test for inorganic sulphates
Specifies a method for a visual comparison of the turbitity obtained by adding a barium chloride solution to a solution of a test portion acidified with hydrochloric acid, with that similarly obtained from a sulphate solution of known concentration. Using a test portion of 100 g, the method is applicable directly to products having inorganic sulphate contents in the range 0,001 % (m/m) to 0,1 % (…
Acetic acid for industrial use — Methods of test — Part 10: Visual limit test for heavy metals (incl...
The principle consists in conversion of heavy metals, such as lead, copper and iron, to their sulphides by treatment with sodium sulphide in ammoniacal solution, and visual comparison of the colour produced with that of a standard lead solution similarly treated. The method detects only the heavy metals present in non-complex form. Using a test portion of 25 g, the method is applicable directly…
