BS-5688-11-1979 ISO-2760-1975.pdf
《BS-5688-11-1979 ISO-2760-1975.pdf》由会员分享,可在线阅读,更多相关《BS-5688-11-1979 ISO-2760-1975.pdf(8页珍藏版)》请在三一文库上搜索。
1、BRITISH STANDARD BS 5688-11: 1979 ISO 2760:1975 Methods of test for Boric acid, boric oxide, disodium tetraborates, sodium perborates and crude sodium borates for industrial use Part 11: Determination of total aluminium content of crude sodium borates ISO title: Crude sodium borates for industrial u
2、se Determination of total aluminium content Titrimetric method NOTEIt is recommended that this Part be read in conjunction with the information in the “General introduction”, published separately as BS 5688-0. UDC 661.65:546.33273:543.062:546.62 Licensed Copy: sheffieldun sheffieldun, na, Mon Dec 04
3、 15:51:33 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5688-11:1979 This British Standard, having been prepared under the direction of the Chemicals Standards Committee, was published under the authority of the Executive Board on 28 February 1979 BSI 12-1999 The following BSI references relate to t
4、he work on this standard: Committee reference CIC/16 Draft for comment 74/53496 DC ISBN 0 580 10544 X National foreword This Part of BS 5688 is identical with ISO 2760 “Crude sodium borates for industrial use Determination of total aluminium content Titrimetric method” published by the International
5、 Organization for Standardization (ISO). Terminology and conventions. The text of the International Standard has been approved as suitable for publication, without deviation, as a British Standard. Some terminology and certain conventions are not identical with those used in British Standards; atten
6、tion is drawn to the following. The comma has been used throughout as a decimal marker. In British Standards it is current practice to use a full point on the baseline as the decimal marker. Where the words “International Standard” appear, referring to this standard, they should be interpreted as “B
7、ritish Standard”. Additional information Water. Water complying with the requirements of clause 3 is specified in BS 3978 “Water for laboratory use”. EDTA. The reagent specified in 3.6 is the disodium salt, dihydrate. WARNING NOTE. Sodium fluoride, the use of which is specified in 5.2, is toxic. Inh
8、alation of dust and contact with the eyes and skin should be avoided. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immu
9、nity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages 1 and 2 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on t
10、he inside front cover. Amendments issued since publication Amd. No.Date of issueComments Licensed Copy: sheffieldun sheffieldun, na, Mon Dec 04 15:51:33 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5688-11:1979 BSI 12-1999i Contents Page National forewordInside front cover 1Scope and field of appli
11、cation1 2Principle1 3Reagents1 4Apparatus1 5Procedure1 6Expression of results2 7Test report2 Licensed Copy: sheffieldun sheffieldun, na, Mon Dec 04 15:51:33 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ii blank Licensed Copy: sheffieldun sheffieldun, na, Mon Dec 04 15:51:33 GMT+00:00 2006, Uncontrolle
12、d Copy, (c) BSI BS 5688-11:1979 BSI 12-19991 1 Scope and field of application This International Standard specifies a titrimetric method for the determination of the total aluminium content of crude sodium borates for industrial use, for material containing up to 1 % aluminium. The method, as descri
13、bed, is not applicable in the presence of zirconium or titanium. More than 0,006 % of iron will interfere in the determination. 2 Principle Fusion of a test portion with sodium carbonate and extraction of the molten mass with hydrochloric acid. Formation of a complex by the addition of the disodium
14、salt of ethylenediaminetetra-acetic acid (EDTA). Decomposition of the complex by sodium fluoride, followed by titration of the liberated EDTA with a standard volumetric solution of zinc chloride in the presence of xylenol orange as indicator. 3 Reagents During the analysis, use only reagents of reco
15、gnized analytical reagent grade, and only distilled water or water of equivalent purity. 3.1 Sodium carbonate, anhydrous. 3.2 Sodium fluoride, crystalline. 3.3 Hydrochloric acid, approximately 6 N solution. 3.4 Ammonia, 1 to 2 N solution. 3.5 Ammonium acetate buffer solution, pH 5,5. Dissolve 50 g o
16、f sodium acetate trihydrate (CH3COONa.3H2O) in water, add 2,5 ml of glacial acetic acid (approximately 17 N) and dilute to 1 000 ml. 3.6 Sodium ethylenediamine-N,N,N,N-tetra-acetate (EDTA), 0,01 M solution. Weigh, to the nearest 0,001 g, 3,725 g of EDTA, dissolve it in water, transfer the solution q
17、uantitatively to a 1 000 ml one-mark volumetric flask, dilute to the mark and mix. 3.7 Zinc, 1 M standard volumetric solution. Remove the oxide film from a sample of pure zinc weighing not less than about 70 g, by washing it with an approximately 2 M solution of hydrochloric acid. Rinse the cleaned
18、zinc with methanol and dry it by washing with diethyl ether. After the ether has evaporated, immediately weigh, to the nearest 0,01 g, 65,37 g of this zinc and dissolve it in 600 ml of the hydrochloric acid solution (3.3). Cool the solution and transfer it quantitatively to a 1 000 ml one-mark volum
19、etric flask, dilute to the mark and mix. NOTESolution of the zinc is facilitated by the introduction of a small piece of platinum wire. 1 ml of this standard volumetric solution corresponds to 51 mg of Al2O3. 3.8 Zinc, 0,01 M standard volumetric solution. Transfer 10,0 ml of the standard volumetric
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- BS-5688-11-1979 ISO-2760-1975 BS 5688 11 1979 ISO 2760 1975
链接地址:https://www.31doc.com/p-3771756.html