(ISo International Standard 7692 INTERNATIONALORGANIZATIONFORSTANDARDIZATION+MEKAYHAPOAHAAOPTAHW3ALMAHOCTAHAAPTW3AIMWORGANISATIONINTERNATIONALEDENORMALISATION Ferrotitanium -- Determination of titanium content Titrimetric method Ferro-titane--Dosagedu titane--Methodetitrimetrique First edition --- 1983-12-15 ISO 7692-1983 (E) UDC 669.15'295-198 : 543.24 : 546.82 Ref.No.ISO7692-1983 (E) Descriptors : ferroalloys, ferrotitanium, chemical analysis, determination of content, titanium, volumetric analysis. Price based on 5 pages Copyright ln No reproduction or networking permitted without license from IHS Not for Resale Foreword ISo (the International Organization for Standardization) is a worldwide federation of national standards bodies (Iso member bodies). The work of developing International Standards is carried out through Iso technical committees. Every member body interested in a subject forwhich a technical committee has been authorized hasthe right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with Iso, also take part in the work. DraftInternational Standards adopted bythe technical committeesare circulated to the member bodies for approval before their acceptance as International Standards by theIso Council. International Standard ISO 7692 was developed by Technical Committee ISO/TC 132, Ferroalloys, and was circuiated to the member bodies in May 1982. It has been approved by the member bodies of the following countries : Austria India Poland Brazil Iran Romania Canada Italy South Africa, Rep. of China Japan Spain Czechoslovakia Korea,Rep.of Sweden Egypt, Arab Rep. of Mexico United Kingdom France Norway USSR Thememberbodyofthefollowing country expressed disapprovalof thedocument on technical grounds : Australia International Organization for Standardization, 1983 Printed in Switzerland Copyright Internaltional Organization for Standardizatior No reproduction or networking permitted without license from IHS Not for Resa ISO7692-1983 (E) INTERNATIONALSTANDARD Ferrotitanium - Determination of titanium content Titrimetric method Scope and field of application 4.1 Aiuminium, of minimum purity 99,5 %, in the form of foil 0,05 mm thick, and free from titanium. This International Standard specifies a titrimetric method for the determination of the titanium content of ferrotitanium. 4.2 Sodium hydrogen carbonate (NaHCO3). The method is applicable to ferrotitanium having titanium con- 4.3 Nitric acid, @ 1,42 g/ml. tentsbetween20and80%(m/m). 4.4 Sulphuric acid, Q 1,84 g/ml. 2Reference 4.5 Hydrochloric acid, 1,19 g/ml. ISO3713, Ferroalloys Sampling and preparation of samples - General rules.1) 4.6 Hydrofluoric acid, @ 1,14 g/ml. 3Principle 4.7 Sulphuric acid, diluted (1 + 1). Dissolution of a test portion using sulphuric, hydrofluoric, nitric Add carefully1volume of the sulphuric acid (4.4)to 1volume and hydrochloric acids. of water. Cool while mixing. Separation of the interfering elements (chromium, vanadium, 4.8 Sulphuric acid, diluted (1 + 4). molybdenum and tin), if present, by precipitation of titanium hydroxide in the presence of hydrogen peroxide. Add carefully 1 volume of the sulphuric acid (4.4) to 4 volumes of water. Cool while mixing. Reduction of the titanium to Ti3+ by aluminium metal in an at- mosphere of carbon dioxide or nitrogen. 4.9 Sodium hydroxide, 100 g/1 solution. Titration of the Ti3+ with standard volumetric iron(ll) ammonium sulphate solution in the presence of thiocyanate as 4.10 Sodium hydroxide, 20 g/l solution. indicator. 4.11 Ammonium thiocyanate, 100 g/l solution. 4 Reagents 4.12 Nitrogen, practically oxygen-free (less than 10 ppm by During the analysis,unless otherwise specified,use only volume),99,998 % pure,or carbon dioxide of similar purity. reagents of recognized analytical grade and only distiled water or water of equivalent purity. 4.13 Hydrogen peroxide, 30 % or 100 volume solution. 1)At present at the stage of draft. 1 Not f