欢迎来到麦多课文档分享! | 帮助中心 海量文档,免费浏览,给你所需,享你所想!
麦多课文档分享
全部分类
  • 标准规范>
  • 教学课件>
  • 考试资料>
  • 办公文档>
  • 学术论文>
  • 行业资料>
  • 易语言源码>
  • ImageVerifierCode 换一换
    首页 麦多课文档分享 > 资源分类 > PDF文档下载
    分享到微信 分享到微博 分享到QQ空间

    BS 6075-8-1981 Methods of sampling and test for sodium hydroxide for industrial use - Determination of sulphate content《工业用氢氧化钠取样和试验方法 第8部分 硫酸盐含量测定》.pdf

    • 资源ID:545698       资源大小:425.26KB        全文页数:16页
    • 资源格式: PDF        下载积分:10000积分
    快捷下载 游客一键下载
    账号登录下载
    微信登录下载
    二维码
    微信扫一扫登录
    下载资源需要10000积分(如需开发票,请勿充值!)
    邮箱/手机:
    温馨提示:
    如需开发票,请勿充值!快捷下载时,用户名和密码都是您填写的邮箱或者手机号,方便查询和重复下载(系统自动生成)。
    如需开发票,请勿充值!如填写123,账号就是123,密码也是123。
    支付方式: 支付宝扫码支付    微信扫码支付   
    验证码:   换一换

    加入VIP,交流精品资源
     
    账号:
    密码:
    验证码:   换一换
      忘记密码?
        
    友情提示
    2、PDF文件下载后,可能会被浏览器默认打开,此种情况可以点击浏览器菜单,保存网页到桌面,就可以正常下载了。
    3、本站不支持迅雷下载,请使用电脑自带的IE浏览器,或者360浏览器、谷歌浏览器下载即可。
    4、本站资源下载后的文档和图纸-无水印,预览文档经过压缩,下载后原文更清晰。
    5、试题试卷类文档,如果标题没有明确说明有答案则都视为没有答案,请知晓。

    BS 6075-8-1981 Methods of sampling and test for sodium hydroxide for industrial use - Determination of sulphate content《工业用氢氧化钠取样和试验方法 第8部分 硫酸盐含量测定》.pdf

    1、BRITISH STANDARD BS 6075-8: 1981 ISO 3198:1975 Methods of Sampling and test for sodium hydroxide for industrial use Part 8: Determination of sulphate content ISO title: Sodium hydroxide for industrial use Determination of sulphur compounds Method by reduction and titrimetry NOTEIt is recommended tha

    2、t this Part be read in conjunction with the information in the “General introduction” published separately as BS 6075-0. UDC 661.322.1:546.33 36:543.24.062:546.226BS6075-8:1981 This British Standard, having been prepared under the directionof the Chemicals Standards Committee, was published under th

    3、e authority ofthe Executive Board and comesinto effect on 27 February 1981 BSI 10-1999 The following BSI reference relates to the work on this standard: Committee reference CIC/22 ISBN 0 580 12058 9 Amendments issued since publication Amd. No. Date of issue CommentsBS6075-8:1981 BSI 10-1999 i Conten

    4、ts Page National foreword ii 1 Scope and field of application 1 2 Reference 1 3 Principle 1 4 Reagents 1 5 Apparatus 1 6 Procedure 2 7 Expression of results 2 8 Test report 3 Annex ISO publications relating to sodium hydroxide for industrial use 6 National appendix Removal of mercury from waste solu

    5、tions 7 Figure 1 Typical apparatus for the determination of sulphur compounds 4 Figure 2 Typical apparatus for the preparation of the reducing solution 5 Publications referred to Inside back coverBS6075-8:1981 ii BSI 10-1999 National foreword This Part ofBS6075 is identical withISO3198 “Sodium hydro

    6、xide for industrial use Determination of sulphur compounds Method by reduction and titrimetry”, published in 1975 by the International Organization for Standardization (ISO). The National appendix to this Part of this standard describes a procedure to remove mercury from waste solutions from the ana

    7、lytical procedures described herein. This procedure is technically equivalent to that described inISO5790 “Inorganic chemical products for industrial use General method for determination of chloride content Mercurimetric method” (which has not been implemented as a British Standard). Terminology and

    8、 conventions. The text of the International Standard has been approved as suitable for publication as a British Standard without deviation. Some terminology and certain conventions are not identical with those used in British Standards; attention is especially drawn to the following. The comma has b

    9、een 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. Wherever the words “International Standard” appear, referring to this standard, they should be read as “British Standard”. The standards listed in the Annex

    10、 are intended for information only. Corresponding British Standards are listed inBS6075-0. Additional information Water. Water complying with the requirements of clause4 is specified inBS3978 “Water for laboratory use”. Hydrochloric acid, approximately 1.18 g/ml, about36% (m/m) solution, which is th

    11、e corresponding reagent available in the UK, is suitable for use in place of the solution specified in4.6. Test portion. For some grades of sodium hydroxide it may be necessary to adjust the mass of the test portion (see6.1) to ensure that the amount of sulphur compounds present in the test solution

    12、 complies with the requirements for the test method. InBS4130 “Sodium hydroxide (technical grades)”, details of a suitable mass for the grades specified are given. WARNINGS Mercury (II) chloride and mercury (II) nitrate, specified in4.4 and4.8 respectively are toxic (with danger of cumulative effect

    13、s) and are irritant particularly in the form of dust. Avoid contact with skin and eyes. Avoid pollution of waste water with mercury from waste solutions using, for example, the procedure for removal of mercury described in the National appendix to this Part of this standard. Cross-reference Internat

    14、ional Standard Corresponding British Standard BS 6075 Methods of sampling and test for sodium hydroxide for industrial use BS 3195:1975 Part 5:1981 Sampling and preparation of main test solution (Identical)BS6075-8:1981 BSI 10-1999 iii Hydriodic acid solution, specified in4.6, gives off harmful vapo

    15、ur and is toxic, corrosive and irritant. Avoid breathing vapour. Prevent contact with eyes and skin. 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

    16、 does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i to iv, pages1to 8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. T

    17、his will be indicated in the amendment table on the inside front cover.iv blankBS6075-8:1981 BSI 10-1999 1 1 Scope and field of application This International Standard specifies a reduction and titrimetric method for the determination of sulphur compounds in sodium hydroxide for industrial use. The

    18、method is applicable to products of which the content of sulphur compounds, expressed as sulphate (SO 4 ), is equal to or greater than5mg/kg. 2 Reference ISO 3195, Sodium hydroxide for industrial use Sampling Test sample Preparation of the main solution for carrying out certain determinations. 3 Pri

    19、nciple Reduction of the sulphur compounds to hydrogen sulphide by heating with a mixture of hydriodic acid and hypophosphorous acid. Absorption of the hydrogen sulphide, entrained in a current of oxygen-free nitrogen, in a mixture of sodium hydroxide and acetone. Titration of the sulphide with stand

    20、ard volumetric mercury (II) nitrate solution in the presence of dithizone as indicator. 4 Reagents During the analysis, use only reagents of recognized analytical reagent grade and only distilled water or water of equivalent purity. 4.1 Acetone 4.2 Nitrogen, oxygen-free. 4.3 Sodium hydroxide, approx

    21、imately1N solution. 4.4 Potassium permanganate and mercury (II) chloride solution, to purify the nitrogen (4.2). Dissolve first2g of potassium permanganate(KMnO 4 ) and then7g of mercury(II) chloride (HgCl 2 ), in100ml of water and filter the solution. 4.5 Pyrogallol solution, to purify the nitrogen

    22、 (4.2). Dissolve15g of pyrogallol in25ml of water and add, while cooling, 150ml of a30% (m/m) potassium hydroxide solution. 4.6 Reduction solution Place in the flask (J) of the apparatus (5.3), shaking after each addition: 50 ml of hypophosphorous acid (H 3 PO 2 ), approximately1,21g/ml, about50% (m

    23、/m) solution; 100 ml of hydrochloric acid, approximately1,19g/ml, about38% (m/m) solution; 120 ml of hydriodic acid, approximately1,97g/ml, about67% (m/m) solution. Assemble the flask and the reflux condenser (K) then, while passing a slow flow of the nitrogen (4.2), boil for4h. Cool to room tempera

    24、ture under a flow of the nitrogen (4.2) and store the reagent away from direct sunlight in an amber glass bottle previously flushed with the nitrogen (4.2) and fitted with a ground glass stopper. 4.7 Sodium sulphate, 0,001 M standard reference solution. Weigh, to the nearest0,0001 g,0,1420 g of anhy

    25、drous sodium sulphate, previously dried at110 C and cooled in a desiccator. Introduce into a 1000 ml one-mark volumetric flask, dissolve in water, dilute to the mark and mix. 1ml of this solution corresponds to96g of SO 4 . 4.8 Mercury (II) nitrate,0,05M standard volumetric solution (=0,1N). Dissolv

    26、e10,85 0,01g of mercury (II) oxide (HgO) in10ml of nitric acid solution, approximately1,40g/ml, about68% (m/m) solution, dilute to 1000 ml with water and mix. NOTEThe strength of the solution thus prepared is sufficiently exact for the small quantities of sulphur compounds to be determined and stand

    27、ardization is therefore unnecessary. In most laboratories, however, a precisely0,1N standard volumetric solution, commonly used for the mercurimetric determination of chlorides, will be available. 4.9 Mercury (II) nitrate,0,001M standard volumetric solution (=0,002N). Dilute20,00ml of the standard v

    28、olumetric mercury(II) nitrate solution (4.8) to the mark in a1000 ml one-mark volumetric flask. Prepare this solution at the time of use. 4.10 Dithizone,0,5g/l solution in the acetone (4.1). 5 Apparatus Ordinary laboratory apparatus and 5.1 Microburette, capacity5ml, graduated in0,01ml (G). 5.2 Appa

    29、ratus for reduction and distillation of which all the components are fitted together with ground glass joints. A typical apparatus is shown inFigure 1 and comprises: 5.2.1 Wash bottles (A and B), Drechsel type, capacity50ml. 5.2.2 Conical flasks (C), capacity100ml. 5.2.3 Reflux condenser (D).BS6075-

    30、8:1981 2 BSI 10-1999 5.2.4 Absorption vessel (E), internal diameter25mm and height100mm. 5.2.5 Dropping funnel (F), capacity50ml. 5.2.6 Stopcocks (1, 2, 3 and 4). 5.3 Apparatus for preparation of the reduction solution (4.6). A typical apparatus is shown inFigure 2, and comprises: 5.3.1 Flask, three

    31、-necked (J), capacity500ml. 5.3.2 Reflux condenser (K). 5.3.3 Nitrogen supply tube (L). 6 Procedure 6.1 Test portion Weigh, to the nearest0,01g, a mass of the test sample (seeISO3195), solid or liquid, not exceeding5or10g respectively, into a dried conical flask (C). Fit with a stopper. 6.2 Check te

    32、st The purpose of this test is to check the gas-tightness and functioning of the apparatus (reduction of sulphur compounds and quantitative recovery of the hydrogen sulphide liberated). Transfer in turn: to the wash bottle (A),25ml of the potassium permanganate and mercury (II) chloride solution(4.4

    33、); to the wash bottle (B),25ml of the pyrogallol solution (4.5); to the absorption vessel (E),5ml of the sodium hydroxide solution (4.3),5ml of the acetone (4.1) and0,1ml of the dithizone solution (4.10); to a dried conical flask (C),2,00ml of the standard reference sodium sulphate solution(4.7) and

    34、 a few glass beads; to the dropping funnel (F),50ml of the reducing solution (4.6); to the microburette (G) the standard volumetric mercury (II) nitrate solution (4.9). Assemble the apparatus taking care to smear the ground joints with a silicone grease and to tighten them with suitable spring-clips

    35、 in order to ensure perfect gas-tightness. Pass the nitrogen (4.2) through stopcocks (2) and (4), at a speed of about2bubbles per second. After5min, run the mercury (II) nitrate solution (4.9), drop by drop, into the absorption vessel (E) until the indicator changes from yellow to red. Open stopcock

    36、s (1) and (3) to allow the reducing solution (4.6) to run into the conical flask (C), leaving a few millimetres of liquid in the dropping funnel (F), then close the two stopcocks. Start the condenser (D) and, while continuing the flow of nitrogen, boil the solution gently in the conical flask (C) fo

    37、r at least30min. The presence of hydrogen sulphide is shown by a colour change of the indicator from red to yellow. Stop the boiling and, while maintaining the flow of nitrogen, titrate the sulphide in the absorption vessel (E) with the standard volumetric mercury (II) nitrate solution (4.9) contain

    38、ed in the microburette(G) until the indicator changes from yellow to red. The result of the check test is considered satisfactory if the volume of the standard volumetric mercury (II) nitrate solution (4.9) used for the titration is between1,90and2,10ml, after subtraction of the blank test result (6

    39、.3). Otherwise check the apparatus for leaks. 6.3 Blank test Carry out a blank test under the same conditions as the check test (6.2), but using2,00ml of water instead of2,00ml of the standard reference sodium sulphate solution (4.7). 6.4 Determination Carry out the determination under the same cond

    40、itions as the check test (6.2), using the test portion (6.1) instead of the2,00ml of the standard reference sodium sulphate solution (4.7). 7 Expression of results The content of sulphur compounds, expressed as milligrams of sulphate (SO 4 ) per kilogram, is given, by the formula where V 0is the vol

    41、ume, in millilitres, of the standard volumetric mercury (II) nitrate solution (4.9) used for the blank test; V 1is the volume, in millilitres, of the standard volumetric mercury (II) nitrate solution (4.9) used for the determination; m is the mass, in grams, of the test portion (6.1); 96 is the mass

    42、, in micrograms, of SO 4corresponding to1ml of the standard volumetric mercury (II) nitrate solution (4.9).BS6075-8:1981 BSI 10-1999 3 8 Test report The test report shall include the following particulars: a) the reference of the method used; b) the results and the method of expression used; c) any

    43、unusual features noted during the determination; d) any operation not included in this International Standard or in the International Standard to which reference is made, or regarded as optional.BS6075-8:1981 4 BSI 10-1999 Figure 1 Typical apparatus for the determination of sulphur compoundsBS6075-8

    44、:1981 BSI 10-1999 5 Figure 2 Typical apparatus for the preparation of the reducing solutionBS6075-8:1981 6 BSI 10-1999 Annex ISO publications relating to sodium hydroxide for industrial use ISO 979, Method of assay. ISO/R 980, Determination of the carbon dioxide content, expressed as sodium carbonat

    45、e Gas-volumetric method. ISO 981, Determination of chloride content Mercurimetric method. ISO/R 982, Determination of sulphate content Barium sulphate gravimetric method. ISO 983, Determination of iron content 1,10-Phenanthroline photometric method. ISO 984, Determination of silica content Reduced s

    46、ilicomolybdic complex photometric method. ISO/R 985, Determination of silica content Gravimetric method by precipitation of the quinoline-silicomolybdic complex. ISO/R 986, Determination of calcium EDTA complexometric method. ISO/R 987, Determination of water-insoluble matter. ISO 3195, Sampling Tes

    47、t sample Preparation of the main solution for carrying out certain determinations. ISO 3196, Determination of carbon dioxide content Titrimetric method. ISO 3197, Determination of chlorides content Photometric method. ISO 3198, Determination of sulphur compounds Method by reduction and titrimetry. I

    48、SO 3697, Determination of calcium and magnesium contents Flame atomic absorption spectrophotometric method.BS6075-8:1981 BSI 10-1999 7 National appendix Removal of mercury from waste solutions A.1 Scope This National appendix describes a method for removing mercury from waste solutions in order to p

    49、revent pollution of waste water. It is recommended principally for waste solutions from titrations using mercury (II) nitrate solution but may be used for other solutions containing mercury. A.2 Principle The mercury in the collected waste solution is precipitated by reaction with alkaline sodium sulphide. Hydrogen peroxide is added to oxidize excess sodium sulphide (to prevent formation of soluble mercury polysulphides), the insoluble mercury salts are removed by decantation and filtr


    注意事项

    本文(BS 6075-8-1981 Methods of sampling and test for sodium hydroxide for industrial use - Determination of sulphate content《工业用氢氧化钠取样和试验方法 第8部分 硫酸盐含量测定》.pdf)为本站会员(李朗)主动上传,麦多课文档分享仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对上载内容本身不做任何修改或编辑。 若此文所含内容侵犯了您的版权或隐私,请立即通知麦多课文档分享(点击联系客服),我们立即给予删除!




    关于我们 - 网站声明 - 网站地图 - 资源地图 - 友情链接 - 网站客服 - 联系我们

    copyright@ 2008-2019 麦多课文库(www.mydoc123.com)网站版权所有
    备案/许可证编号:苏ICP备17064731号-1 

    收起
    展开