1、BRITISH STANDARD BS3907-6: 1969 Method for The determination of zirconium in magnesium and magnesium alloys (Photometric method) Methods for the analysis of magnesium and magnesium alloysBS3907-6:1969 This BritishStandard, having been approved by the Non-ferrous Metals Industry Standards Committee,
2、was published under the authority ofthe Executive Board on 14March1969 BSI 12-1999 The following BSI references relate to the work on this standard: Committee referencesNFE/23 andNFE/23/4 Draft for comment66/25085 ISBN 0 580 04449 1 Co-operating organizations The Non-ferrous Metals Industry Standard
3、s Committee, under whose supervision this BritishStandard was prepared, consists of representatives from the following Government departments and scientific and industrial organizations: The Government department and scientific and industrial organizations marked with an asterisk in the above list,
4、together with the following, were directly represented on the committee entrusted with the preparation of this BritishStandard: Aluminium Federation Institution of Mining and Metallurgy Association of Bronze and Brass Founders Institution of Production Engineers Association of Consulting Engineers I
5、nstitution of Structural Engineers Board of Trade Lead Development Association British Bronze and Brass Ingot Light Metal Founders Association Manufacturers Association London Metal Exchange British Electrical and Allied Manufacturers Magnesium Industry Council* Association Ministry of Defence, Army
6、 Department* British Lead Manufacturers Association Ministry of Defence, Navy Department British Non-ferrous Metals Federation National Brassfoundry Association British Non-Ferrous Metals Federation Non-ferrous Metal Stockists* High Conductivity Copper Group Post Office British Non-ferrous Metals Re
7、search Royal Institute of British Architects Association* Society of British Aerospace Companies Ltd. Copper Development Association Society of Motor Manufacturers and Crown Agents for Oversea Governments Traders Ltd.* and Administrations Tin Research Institute Electric Cable Makers Confederation Zi
8、nc Development Association Institute of British Foundrymen Individual manufacturer Institute of Metals Institution of Mechanical Engineers (Automobile Division) Institute of Sheet Metal Engineering Ministry of Technology, Laboratory of the Ministry of Technology Government Chemist Individual analyst
9、s Amendments issued since publication Amd. No. Date CommentsBS3907-6:1969 BSI 12-1999 i Contents Page Co-operating organizations Inside front cover Foreword ii 1 Introduction 1 2 Apparatus 1 3 Solutions required 1 4 Sampling 2 5 Procedure 2 6 Assay of the stock zirconium solution 3 7 Calibration 4 8
10、 Calculation 4BS3907-6:1969 ii BSI 12-1999 Foreword This standard makes reference to the following BritishStandards: BS1499, Sampling non-ferrous metals. BS3978, Water for laboratory use. This method for the photometric determination of zirconium in magnesium and magnesium alloys is the sixth of a s
11、eries which will form a complete BritishStandard under the collective title “Methods for the analysis of magnesium and magnesium alloys” each being published as a separate part. Other methods in the series are as follows: Part1: Aluminium in magnesium alloys (gravimetric method); Part2: Iron in magn
12、esium and magnesium alloys (photometric-1 : 10-phenanthroline method); Part3: Copper in magnesium and magnesium alloys (photometric method); Part4: Manganese in magnesium and magnesium alloys (photometric-periodate method); Part5: Manganese in magnesium and magnesium alloys (photometric-periodate me
13、thod) (low contents); Part7: Nickel in magnesium alloys (photometric method); Part8: Total rare earths in magnesium alloys (gravimetric method) 1) ; Part9: Zinc in magnesium alloys (ion exchange volumetric-EDTA method); Part10: Manganese in magnesium alloys containing zirconium, rare earths or thori
14、um (photometric method). The preparation of this series of methods has been authorised by the Non-ferrous Metals Industry Standards Committee as part of a general programme for the standardization of methods for the sampling and analysis of non-ferrous metals. The methods have been found to give rel
15、iable and reproducible results and, while in some instances they may appear to be lengthy, it should be appreciated that they are primarily intended as “referee” methods to be used in cases of dispute. This method is substantially the same as the corresponding method approved by ISO/TC79 which will
16、be published as ISO R . . . 1) . 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 immunity from legal obligations. Summary
17、of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1 to4, an inside back cover 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 the inside front cove
18、r. 1) In course of preparation.BS3907-6:1969 BSI 12-1999 1 1 Introduction 1.1 Principle. The sample is attacked with hydrochloric acid (4N) and the insoluble matter removed by filtration and reserved for the determination of “insoluble” zirconium. The filtrate is used for the determination of “solub
19、le” zirconium. The “soluble” zirconium is determined on an aliquot of the filtrate by adjusting the acidity to about1.5N and developing the zirconium-alizarin sulphonate complex, the intensity of which is measured. The “insoluble” zirconium is brought into solution using hydrofluoric acid, fluoride
20、is removed by fuming with perchloric acid, and the zirconium determined using sodium alizarin sulphonate. 1.2 Range. The method is suitable for “soluble” zirconium contents between0.1% and1.0% and “insoluble” zirconium contents between0.02% and0.3%. 1.3 Reproducibility. Experiments have been carried
21、 out independently by a number of analysts using this method. The degree of reproducibility that can be expected is shown by the following analysis of the results obtained. 1.4 Application. The method is suitable for alloys containing zinc, rare earth elements, thorium, silver, lead or bismuth. 2 Ap
22、paratus 2.1 Class A volumetric glassware complying with the appropriate BritishStandards shall be used throughout. 2.2 Any instrument suitable for measuring the optical density of the solution at a wavelength of525nm may be used with2cm cells. Alternatively when a filter photometer of the balanced t
23、wo-cell type is used, the following conditions have been found suitable: Tungsten or mercury vapour lamp Ilford604 or605 filter withH503 heat filter or equivalent filters 2cm cells. 3 Solutions required All reagents shall be of the highest purity obtainable and either distilled or demineralized wate
24、r complying with BS3978 2)shall be used throughout. Solutions shall be freshly prepared and where necessary filtered. Stock zirconium (1mlN 5mg of zirconium). Dissolve1.77g of dry zirconium oxychloride 3)(ZrOCl 2 .8H 2 O) in water, add10ml of hydrochloric acid (sp. gr.1.161.18), filter, transfer to
25、a100ml volumetric flask, dilute to the mark and mix. Assay this solution. Standard zirconium (1mlN 0.1mg of zirconium). Having assayed the stock solution, dilute a quantity of this accurately to give a solution containing exactly0.100g of zirconium per litre. Alloying constituents Soluble Insoluble
26、Zinc Thorium Rare earths Silver Zirconium content Standard deviation Zirconium content Standard deviation % 2 1 4 6 % 1“ % 3“ 1“ % 2“ % 0.15 0.33 0.51 0.67 0.76 % 0.006 0.006 0.020 0.016 0.016 % 0.03 0.02 0.09 0.10 0.10 % 0.004 0.002 0.013 0.015 0.015 2) BS3978 “Water for laboratory use”. 3) Zirconi
27、um oxychloride may contain up to3% of hafnium oxychloride. Hafnium has only one-quarter the molar extinction of zirconium. It is sufficient that the crystals appear dry. Any attempt to dry the crystals in an oven might convert some of the zirconium to a form which although soluble and capable of pre
28、cipitation by mandelic acid, does not readily form the colour with alizarin.BS3907-6:1969 2 BSI 12-1999 Alternatively: Standard zirconium (1ml=0.1mg of zirconium). Weigh0.500g of zirconium(99.9%minimum) into a dry beaker, add30ml of methanol and5ml of bromine keeping the beaker cool during the initi
29、al attack. When the vigorous action has ceased warm slightly until solution is complete. Add20ml of hydrochloric acid (sp.gr.1.161.18), heat to boiling and continue boiling until the solution is colourless, maintaining the volume of about50ml by the addition of water. Cool, transfer to a100ml volume
30、tric flask, dilute to the mark and mix. Transfer20ml of this solution to a1-litre volumetric flask, dilute to the mark and mix. Hydrochloric acid (2%v/v). Dilute20ml of hydrochloric acid (sp. gr.1.161.18) to1 litre and mix. Mandelic acid (15%w/v). Dissolve150g of mandelic acid in water, dilute to1 l
31、itre and mix. Magnesium chloride (42%w/v). Dissolve42g magnesium chloride (MgCl 2 .6H 2 O) in water, dilute to100ml and mix. Sodium alizarin sulphonate (0.15%w/v). Dissolve1.5g of sodium alizarin sulphonate in about300ml of warm water, filter, cool, dilute to1 litre and mix. Mandelic acid-hydrochlor
32、ic acid wash. Dissolve50g of mandelic acid in hydrochloric acid(2%), dilute to1litre with hydrochloric acid(2%) and mix. 4 Sampling Recommended methods of obtaining a suitable sample for the analytical procedure given below are described in BS1499 “Sampling non-ferrous metals”. 5 Procedure 5.1 Zirco
33、nium “soluble” in4N acid 5.1.1 Adjust the weight of sample to be used as follows: 5.1.2 Carry out simultaneously a blank determination following the same procedure and using the same amounts of reagents as with the sample. 5.1.3 Transfer the appropriate weight of sample to a beaker of suitable capac
34、ity (e.g.600ml) add20ml of water for each1g of sample, then add slowly10ml of hydrochloric acid (sp. gr.1.161.18) for each1g of sample. When the vigorous reaction appears to subside add5ml of hydrogen peroxide(20vol), allow to stand for10 minutes then boil the solution for exactly5minutes. Add50ml o
35、f water and cool to room temperature. 5.1.4 Filter the solution through a medium texture filter paper, or paper pulp pad and wash thoroughly with water. Reserve the residue for the determination of “insoluble” zirconium. 5.1.5 Transfer the filtrate to a500ml volumetric flask, dilute to the mark and
36、mix. Immediately transfer by means of a pipette a10ml aliquot to a100ml conical flask. Add2.5ml of hydrochloric acid (sp. gr.1.161.18) and10.0ml of sodium alizarin sulphonate solution(0.15%). 5.1.6 Place the flask in a boiling water bath and maintain at this temperature for2“3“ minutes without over
37、heating. Quickly cool the flask and its contents to room temperature in a cold water bath and add2.0ml of hydrochloric acid (sp. gr.1.161.18). Transfer the solution to a100ml volumetric flask, dilute to the mark and mix. 5.1.7 Measure the optical density within one hour using the conditions specifie
38、d under “Apparatus”. Zirconium content Weight of sample Over Up to and including % 0.1 0.3 % 0.3 1.0 g 6 0.001 4 0.001BS3907-6:1969 BSI 12-1999 3 5.2 “Insoluble” zirconium 5.2.1 Transfer the residue reserved in5.1.4 to a platinum crucible of suitable capacity (e.g.40ml), dry carefully, and ignite at
39、600800 C to remove all carbon. Allow to cool, add5ml of water, 1ml of hydrofluoric acid 4)and2ml of perchloric acid (sp. gr.1.54). 5.2.2 Carry out simultaneously a blank determination following the same procedure and using the same amounts of reagent as with the sample. 5.2.3 Carefully evaporate alm
40、ost to dryness and allow to cool. Wash the walls of the crucible with a little water and add a further2ml of perchloric acid (sp. gr.1.54). 5.2.3.1 For alloys not containing silver. Repeat the fuming procedure then transfer the contents of the crucible to a100ml volumetric flask, thoroughly washing
41、the crucible with water and adding the washings to the flask. Dilute to the mark and mix thoroughly. 5.2.3.2 For alloys containing silver. Repeat the fuming procedure then transfer the contents of the crucible to a250ml beaker thoroughly washing the crucible with water and adding the washings to the
42、 beaker. Add15ml of hydrochloric acid (sp. gr.1.161.18), boil for1 minute, dilute to about50ml and boil for several minutes to coagulate the silver chloride and cool to room temperature. Filter into a100ml volumetric flask, wash the precipitate thoroughly with water, dilute to the mark and mix. 5.2.
43、4 Transfer by means of a pipette, the appropriate aliquot indicated in the table below to a100ml conical flask. 5.2.4.1 For alloys not containing silver. Add2.5ml of hydrochloric acid (sp. gr.1.161.18) and10.0ml of sodium alizarin sulphonate solution(0.15%) and continue from5.1.6. 5.2.4.2 For alloys
44、 containing silver Add: 1ml of hydrochloric acid (sp. gr.1.161.18) for a10ml aliquot. 1.75ml of hydrochloric acid (sp. gr.1.161.18) for a5ml aliquot. then add10.0ml of sodium alizarin sulphonate solution(0.15%) and continue from5.1.6. 6 Assay of the stock zirconium solution 6.1 Transfer by means of
45、a pipette, 10ml of stock zirconium solution(1mlN 5mg of zirconium) to a beaker of suitable capacity(e.g.250ml). Dilute to about40ml and add30ml of hydrochloric acid (sp. gr.1.161.18). Boil and add50ml of mandelic acid solution(15%). 6.2 Allow to stand at80 C for20 minutes then allow to cool and filt
46、er through a medium texture filter paper. Wash the filter thoroughly with mandelic acid-hydrochloric acid wash solution and allow to drain. 6.3 Transfer the filter to a weighed platinum crucible, dry and char the paper and ignite carefully to constant weight at9501000 C. 6.4 Weigh the ignited residu
47、e as zirconium oxide (ZrO 2 ). Zirconium content of stock solution=mg of Zr perml where C =weight(mg) of ignited zirconium oxide. 4) This refers to the usual analytical reagent grade of40%w/w. Zirconium content Size of aliquot Over Up to and including % 0.02 0.1 % 0.15 0.3 ml 10 5+5ml of water C 0.7
48、4 10 -BS3907-6:1969 4 BSI 12-1999 7 Calibration 7.1 Into each of a series of nine100ml conical flasks, each containing an equivalent of0.10g of magnesium as2ml of magnesium chloride solution(42%), transfer0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0ml of standard zirconium solution(1ml=0.1mg of zirconi
49、um). 7.2 Add sufficient water(i.e.8.0, 7.0, 6.0, 5.0, 4.0, 3.0, 2.0, 1.0, 0ml) to bring the volume to exactly10.0ml. Add2.5ml of hydrochloric acid (sp. gr.1.161.18) and10.0ml of sodium alizarin sulphonate(0.15per cent) and continue from5.1.6. 7.3 Measure the optical density using the conditions specified under “Apparatus”, and prepare a calibration graph by plotting the optical density against the weight(mg) of zirconium. 8 Calculation Convert the optical density reading corrected for
