1、BRITISH STANDARD BS7317-6:1990Methods forAnalysis of high purity copper cathodeCu-CATH-1Part 6: Method for determination of phosphorus and silicon by spectrophotometryUDC669.3.015.4:543.422.062:546.18+546.28BS7317-6:1990This BritishStandard, having been prepared under the directionof the Non-ferrous
2、 Metals Standards Policy Committee, was published underthe authority of the BoardofBSI and comesintoeffecton31July1990 BSI01-2000The following BSI references relate to the work on this standard:Committee referenceNFM/34Draft for DevelopmentDD95-6ISBN 0 580 18465 XCommittees responsible for this Brit
3、ish StandardThe preparation of this BritishStandard was entrusted by the Non-ferrous Metals Standards Policy Committee(NFM/-) to Technical CommitteeNFM/34, upon which the following bodies were represented:British Bathroom CouncilBritish Cable Makers ConfederationBritish Gas plcBritish Malleable Tube
4、 Fittings AssociationBritish Non-ferrous Metals FederationBritish Valve and Actuator Manufacturers AssociationCopper Development AssociationLondon Metal ExchangeNon-ferrous Metal StockistsSociety of British Aerospace Companies Ltd.Transmission and Distribution Association (BEAMA Ltd.)Coopted members
5、The following bodies were also represented in the drafting of the standard, through subcommittees and panels:BNF Metals Technology CentreBritish Bronze and Brass Ingot Manufacturers AssociationBureau of Analysed Samples Ltd.Copper Smelters and Refiners AssociationMinistry of DefenceAmendments issued
6、 since publicationAmd. No. Date of issue CommentsBS7317-6:1990 BSI 01-2000 iContentsPageCommittees responsible Inside front coverForeword ii1 Scope 12 Principle 13 Reagents 14 Apparatus 25 Procedure for phosphorus 26 Procedure for silicon 37 Repeatability and reproducibility 48 Test report 4Table 1
7、Phosphorus calibration solutions 2Table 2 Silicon calibration solutions 3Publications referred to Inside back coverBS7317-6:1990ii BSI 01-2000ForewordBS7317 has been prepared under the direction of the Non-ferrous Metals Standards Policy Committee. It describes methods for the determination of impur
8、ity elements in high purity copper cathode designatedCu-CATH-1, each method being published as a separate Part.The methods are based on those previously issued in the Draft for Development series DD95-1 to DD95-7. The information and experience gained from the practical application of DD95 have been
9、 taken into account in the methods in BS7317.This Part of BS7317 supersedes DD95-6:1987, which is withdrawn. It is one of a series of methods in BS7317, the others being as follows: Part 1: Method for determination of cadmium, manganese and silver (screening procedure for chromium, cobalt, iron, nic
10、kel and zinc) by atomic absorption spectrophotometry; Part 2: Method for determination of chromium, cobalt, iron, nickel and zinc by discrete volume nebulization atomic absorption spectrophotometry; Part 3: Method for determination of antimony, arsenic, bismuth, selenium, tellurium and tin by hydrid
11、e generation and atomic absorption spectrophotometry; Part 4: Method for determination of antimony, arsenic, bismuth, lead, selenium, tellurium and tin by electrothermal atomization atomic absorption spectrophotometry; Part 5: Method for determination of sulphur by hydrogen sulphide evolution and sp
12、ectrophotometry; Part 7: Method for determination of lead by lanthanum hydroxide separation and atomic absorption spectrophotometry.The atomic absorption spectrophotometric procedures in Parts1 and2 are complementary. A sample solution concentration found to be satisfactory for nebulizers in standar
13、d atomic absorptiometers was20g/L. At this concentration the precision obtainable, using the method described in Part1, is only sufficient to allow the determination of cadmium, manganese and silver. Results would be obtained for chromium, cobalt, iron, nickel and zinc that would prove useful in det
14、ecting impurities grossly in excess of the requirements for chemical composition specified in BS6017 for Cu-CATH-1 and would give a guide to the levels to be determined by Part2.The discrete volume nebulization procedure in Part2 was developed to enable a higher equivalent sample solution concentrat
15、ion of100g/L to be used without nebulizer blockage. The method involves no chemical separation, which can give rise to contamination problems, and the extra sensitivity obtained enables the impurities to be determined to an adequate accuracy for the requirements for chemical composition specified in
16、 BS6017 for Cu-CATH-1.Parts1 and2 essentially cover the same impurities. Part4 covers the electrothermal atomization atomic absorption spectrophotometric method and is recommended where the facility is available. Parts1,2,3 and7 are included for use where the electrothermal atomization equipment is
17、not available.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 of pagesThis document
18、 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 cover.BS7317-6:1990 BSI 01-
19、2000 11 ScopeThis Part of BS7317 describes a method for the determination of the actual amounts of the impurity elements phosphorus and silicon present in high purity copper cathode (designated Cu-CATH-1), by spectrophotometry. It is applicable to concentrations of the elements not exceeding the fol
20、lowing limits: NOTEThe titles of the publications referred to in this Part of BS7317 are listed on the inside back cover.2 PrincipleSeparate samples are taken for phosphorus and silicon and are dissolved respectively in nitric acid and in a nitric/hydrofluoric acid mixture. The phosphorus and silico
21、n present in the samples are converted to the heteropolymolybdate complexes, separated by extraction into organic solvents and determined spectrophotometrically as the reduced complexes.3 Reagents3.1 GeneralDuring the analysis, use only reagents of the highest recognized analytical quality, as free
22、as possible from phosphorus and silicon, and only water that has been double distilled from a quartz apparatus, or water of equivalent purity. Do not use demineralized water.Store all reagents used for the silicon determination in containers made from materials free from silicon, such as polyethylen
23、e. Do not use glass pipettes for solutions that are to be used in the silicon determinations (seenote to4.3).3.2 Hydrogen peroxide,30%m/m3.3 Methanol3.4 Hydrofluoric acid, 1.13g/mL.3.5 4-methylpentan-2-one3.6 Acetone3.7 Nitric acid, 1.42g/mL,50%V/V solution.3.8 Hydrochloric acid, 1.18g/mL,50%V/V sol
24、ution.3.9 Hydrochloric acid, 1.18g/mL,10%V/V solution.3.10 Oxalic acid solution. Dissolve50g of oxalic acid (COOH)2.2H2O in500mL of water.3.11 Orthoboric acid solution, saturated.3.12 Copper(II) nitrate solution. Dissolve152g of copper(II) nitrate Cu(NO3)2.3H2O in600mL of water. Filter if necessary.
25、 Add8mL of50%V/V nitric acid solution(3.7) and dilute to800mL.3.13 Ammonium molybdate solution. Dissolve100g of ammonium molybdate (NH4)6Mo7O24.4H2O in1000mL of water.3.14 Hydrazinium chloride solution. Dissolve5g of hydrazinium chloride (NH2)22HCl in500mL of10%V/V hydrochloric acid solution(3.9).3.
26、15 Mixed solvent, prepared by mixing25 parts by volume of amyl alcohol with75 parts by volume of diethyl ether.3.16 Tin(II) chloride stock solution. Dissolve25g of tin(II) chloride (SnCl2) in250mL of concentrated hydrochloric acid( 1.18g/mL).3.17 Tin(II) chloride dilute solution. Dilute one part by
27、volume of tin(II) chloride stock solution(3.16) with nine parts by volume of water.3.18 Copper(II) nitrate-tetrafluoroboric acid solution. Dissolve76g of copper(II) nitrate Cu(NO3)2.3H2O in300mL of water. Add6mL of50%V/V nitric acid solution(3.7) and dilute to600mL. Add10g of orthoboric acid (H3BO3)
28、, warm to about50C and stir for30min. Cool and filter through a fast filter paper. Add1.0mL of hydrofluoric acid(3.4).3.19 Phosphorus reference solution. Dissolve3.72g of ammonium dihydrogen orthophosphate (NH4H2PO4) in water. Transfer to a1L volumetric flask and dilute to the mark. Mix well.NOTEIn1
29、mL of this solution there is1mg of phosphorus.3.20 Silicon reference solution. Use a commercially available standard solution, having a concentration of1mL corresponding to1mg of silicon. Alternatively, prepare the silicon reference solution by the following method. Heat approximately10g of finely g
30、round silica for1h at1000C. Remove the silica from the furnace and allow it to cool in a desiccator containing diphosphorus pentaoxide. Weigh2.140 0.001g of this silica in a platinum dish. Add10g of anhydrous sodium carbonate to the dish, mix well, preferably with a platinum spatula, and fuse carefu
31、lly until a clear and transparent melt is obtained.Allow to cool, add warm water, heat gently until completely dissolved and transfer the solution to a beaker made of material free from silica. Allow to cool again, dilute to about500mL, transfer to a1000mL volumetric flask, dilute to the mark and mi
32、x well.Transfer the solution immediately to a container free from silica.NOTEIn1mL of this solution there is1mg of silicon.Do not keep the solution for more than one month.phosphorus 204g/g(0.0020%m/m) maximum;silicon 254g/g(0.0025%m/m) maximum.BS7317-6:19902 BSI 01-20004 Apparatus4.1 Spectrophotome
33、ter, equipped with10mm path length glass cells, suitable for measuring the optical density (absorbance) of a solution at wavelengths of625nm and742nm.4.2 Self-adhesive plastics filmNOTE“Cling film”, as used for culinary purposes, has been found to be suitable.4.3 Ordinary laboratory apparatus. Plast
34、ics ware is to be used where appropriate in the method for the determination of silicon.NOTEFor the measurement and addition of reagents, plastics hypodermic syringes, with plastics tubing in place of the needle, have been found to be useful.5 Procedure for phosphorus5.1 GeneralScrupulously clean al
35、l glassware in nitric acid solution(3.7) for16h. Rinse with distilled water and dry, immediately before use.Do not use surfactant solutions for cleaning, many of which contain phosphorus.5.2 Preparation of the calibration graph5.2.1 Calibration solutions. Into each of five500mL beakers pipette40mL o
36、f the copper(II) nitrate solution(3.12). Add, using micropipettes, the amounts of phosphorus reference solution(3.19) given in Table 1.Transfer the contents of each beaker to a125mL separating funnel and dilute to50mL.5.2.2 Extraction and colour development. Add successively, with mixing,2.0mL of50%
37、V/V hydrochloric acid solution(3.8),10 0.2mL of ammonium molybdate solution(3.13) and1004L of hydrogen peroxide(3.2) to each separating funnel. Allow to stand for5min.Add25mL of the mixed solvent solution(3.15) and extract for30s.Allow the phases to settle. Separate the lower aqueous phase completel
38、y and discard.Wash the solvent in the separating funnel with10mL of10%V/V hydrochloric acid solution(3.9) and discard the aqueous layer.Add to the mixed solvent in the separating funnel10mL of hydrazinium chloride solution(3.14) and shake for10s.Add10mL of tin(II) chloride dilute solution(3.17) and
39、shake for a further30s. Allow the layers to settle, and completely separate and discard the lower aqueous phase.Transfer the solvent phase into a previously washed and dried25mL volumetric flask, dilute to the mark with methanol(3.3) and mix well. Table 1 Phosphorus calibration solutions5.2.3 Spectr
40、ophotometric measurements. After1min but before5min, carry out the absorption measurements on each solution extract using the spectrophotometer(4.1) adjusted to a wavelength of625nm using a cell of10mm path length.NOTEAs a guide, the absorbance of a solution containing404g of phosphorus is about0.8.
41、5.2.4 Plotting the calibration graph. Deduct the absorbance obtained for solution5.2.1.1 from that obtained for each of the other calibration solutions, to give the corrected absorbance values.Plot, or compute, a graph of the corresponding microgram per gram phosphorus contents against the corrected
42、 absorbance values.5.2.5 Mean difference () for the calibration graph. From the calibration read off, or calculate, an apparent phosphorus concentration, in microgram per gram, corresponding to each of the measured absorbances. Calculate the differences between the apparent concentrations and the tr
43、ue concentrations. Sum these differences arithmetically (i.e.ignoring the signs) and divide by the number of measurements(5) to give the mean difference ().The mean difference() should not exceed0.54g/g.5.3 Determinations5.3.1 Dissolution of the test sample. Carry out the following operations in tri
44、plicate.Weigh2.0 0.01g of the test sample and transfer it into a500mL glass conical beaker. Add20mL of50%V/V nitric acid solution(3.7) and leave to dissolve. Evaporate gently, without a cover glass, on a hot plate until the solution becomes syrupy, the meniscus retreating from the side of the beaker
45、.Remove from the hot plate and allow to cool. Dilute to about40mL with water, transfer to a125mL separating funnel and dilute to50mL.5.3.2 Blank test. Carry out the following operations in triplicate.Calibration solutionsAddition of phosphorus reference solutionCorresponding phosphorus contents in a
46、2g sample5.2.1.15.2.1.25.2.1.35.2.1.45.2.1.54L0102030404g/g05101520BS7317-6:1990 BSI 01-2000 3Prepare a blank solution by evaporating20mL of50%V/V nitric acid solution(3.7) in a500mL conical beaker to about1mL. Cool. Dilute to about40mL with water, transfer to a125mL separating funnel and dilute to5
47、0mL.5.3.3 Extraction and colour development. Using the solutions prepared in5.3.1 and5.3.2, proceed with the extraction and colour development as described in5.2.2.5.3.4 Spectrophotometric measurements. Carry out the spectrophotometric measurements on the extracts from5.3.3 as described in5.2.3.5.4
48、Calculation and expression of resultsCalculate the arithmetic mean of the absorbances from the blank solutions(5.3.2). Subtract this from the arithmetic mean of the absorbances for the test solutions(5.3.1) and read off or calculate the phosphorus concentration of the test sample in microgram per gr
49、am.6 Procedure for silicon6.1 GeneralScrupulously clean all glass and plastics ware in nitric acid solution(3.7) for16h. Rinse with distilled water and dry, immediately before use.Do not use surfactant solutions, many of which contain silicon.6.2 Preparation of the calibration graph6.2.1 Calibration solutions. Into each of six50mL plastics beakers add30mL of copper(II)nitrate-tetrafluoroboric acid solution(3.18) (seenote to4.3). Add, using micropipettes, the amounts of silicon reference solution(3.20) given in Table 2.Transfer the contents
