1、BRITISH STANDARDBS ISO 17812:2007Paper, board and pulps Determination of total magnesium, total calcium, total manganese, total iron and total copperICS 85.040; 85.060g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g5
2、3g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS ISO 17812:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 December 2007 BSI 2007ISBN 978 0 580 54030 1National forewordThis British Standard is the UK implementation
3、 of ISO 17812:2007.The UK participation in its preparation was entrusted to Technical Committee PAI/11, Methods of test for paper, board and pulps.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the ne
4、cessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.Amendments issued since publicationAmd. No. Date CommentsReference numberISO 17812:2007(E)INTERNATIONAL STANDARD ISO17812First edition2
5、007-12-01Paper, board and pulps Determination of total magnesium, total calcium, total manganese, total iron and total copper Papier, carton et ptes Dtermination de la teneur en magnsium total, en calcium total, en manganse total, en fer total et en cuivre totalBS ISO 17812:2007ii iiiContents Page F
6、oreword iv Introduction v 1 Scope . 1 2 Normative references . 1 3 Principle. 1 4 Reagents and materials . 2 5 Apparatus and equipment . 3 6 Sampling and preparation of sample 3 7 Procedure 3 8 Preparation of calibration solutions . 5 9 Blank solution . 6 10 Determination 6 11 Calculation. 7 12 Prec
7、ision 7 13 Test report . 8 BS ISO 17812:2007iv Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each me
8、mber body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International E
9、lectrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards ad
10、opted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of pa
11、tent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 17812 was prepared by Technical Committee ISO/TC 6, Paper, board and pulps. BS ISO 17812:2007vIntroduction This International Standard combines the determination of magnesium (Mg), calcium (Ca), mangane
12、se (Mn), iron (Fe) and copper (Cu) into one single standard. The scope of this International Standard includes the acid-soluble part of the elements plus that part of the elements that may remain insoluble after dissolution of the incineration residue with hydrochloric acid. This International Stand
13、ard is complementary to the following International Standards, which measure only the acid-soluble part of the element. ISO 777, Paper, board and pulp Determination of acid-soluble calcium ISO 778, Paper, board and pulp Determination of acid-soluble copper ISO 779, Paper, board and pulp Determinatio
14、n of acid-soluble iron ISO 1830, Paper, board and pulps Determination of acid-soluble manganese BS ISO 17812:2007blank1Paper, board and pulps Determination of total magnesium, total calcium, total manganese, total iron and total copper WARNING The method specified in this International Standard invo
15、lves the use of some hazardous chemicals and of gases that can form explosive mixtures with air. Care should be taken to ensure the relevant precautions are observed. 1 Scope This International Standard specifies the procedure for the determination of total magnesium, total calcium, total manganese,
16、 total iron and total copper by atomic absorption spectrometry or by plasma emission spectrometry. The total content comprises the acid-soluble part of the element plus the acid-insoluble part of the element. It is applicable to all types of paper, board and pulps. 2 Normative references The followi
17、ng referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 186, Paper and board Sampling to determine average quali
18、ty ISO 287, Paper and board Determination of moisture content of a lot Oven drying method ISO 638, Paper, board and pulps Determination of dry matter content Oven-drying method ISO 1762, Paper, board and pulps Determination of residue (ash) on ignition at 525 C ISO 7213, Pulps Sampling for testing 3
19、 Principle A test specimen is incinerated at 525 C and the residue is dissolved in 6 mol/l hydrochloric acid. If the resulting solution contains insoluble material, originating, for example, from fillers and coating formulations, these shall be destroyed. Two alternative methods for destroying the i
20、nsoluble material are included in this International Standard: hydrofluoric acid digestion (7.3.2) and fusion with alkali metal salts (7.3.3). This insoluble part should be combined with the original solution. This is to ensure complete recovery of elements that may be occluded in the residue or com
21、bined with silicates. The concentration of each element in the test solution is then determined by atomic absorption or plasma emission spectrometry, as specified in this International Standard. BS ISO 17812:20072 4 Reagents and materials 4.1 General All chemicals shall be of reagent grade or better
22、, unless otherwise indicated. Water shall be distilled or deionized with a maximum conductivity of 1,0 S/cm at 25 C. 4.2 Hydrochloric acid (HCl), about 6 mol/l. Dilute 500 ml of concentrated hydrochloric acid (specific gravity 1,19 g/ml) to 1 000 ml with water. 4.3 Hydrofluoric acid (HF), 48 % to 52
23、 % solution. 4.4 Sulfuric acid (H2SO4), concentrated (specific gravity 1,84 g/ml). 4.5 Lanthanum chloride (LaCl3), solution, c(La) = 50 g/l. In a volumetric flask, dissolve 59 g of lanthanum oxide (La2O3) in small portions, in 200 ml of hydrochloric acid (4.2) and dilute to 1 000 ml with water. NOTE
24、 This lanthanum solution is used to eliminate chemical interference when determining magnesium in an air/acetylene flame. The solution is not required when the nitrous oxide/acetylene flame or inductively coupled plasma (ICP) technique is used. 4.6 Nitric acid (HNO3), concentrated (specific gravity
25、1,4 g/ml). 4.7 Standard stock solutions of each element, commercially available Certified Atomic Absorption or Atomic Emission standard solutions can be used. Standard stock solutions can also be prepared as follows: Magnesium, 1 000 mg/l standard solution. Dissolve 1,000 g of magnesium metal ribbon
26、 in 100 ml of 1:4 nitric acid (4.6) and dilute to 1 000 ml with water. Calcium, 1 000 mg/l standard solution. Dissolve 2,497 g of primary standard calcium carbonate (CaCO3) in a minimum volume of 1:4 nitric acid (4.6) and dilute to 1 000 ml with water. Manganese, 1 000 mg/l standard solution. Dissol
27、ve 1,000 g of manganese metal strip or wire in a minimum volume of 1:1 nitric acid (4.6) and dilute to 1 000 ml with water. Iron, 1 000 mg/l standard solution. Dissolve 1,000 g of iron metal strip or wire in 20 ml of hydrochloric acid (4.2) and dilute to 1 000 ml with water. Copper, 1 000 mg/l stand
28、ard solution. Dissolve 1,000 g of copper metal strip or wire in a minimum volume of 1:1 nitric acid (4.6) and dilute to 1 000 ml with water. 4.8 Acetylene gas and/or nitrous oxide gas, of a grade suitable for atomic absorption spectrometry. Nitrous oxide is used only when measuring calcium. WARNING
29、Acetylene gas forms explosive mixtures with air. 4.9 Carrier gas, appropriate gas for the plasma emission spectrometer. Argon is usually recommended as a carrier gas. 4.10 Alkali metal salts, mix sodium carbonate (Na2CO3) and boric acid (H3BO3) in the required amounts in the weight portions 3:1. NOT
30、E Other alkali metal salts can also be used for example lithium metaborate (LiBO2) 4.11 Cesium chloride (CsCl), solution, (Cs) = 50 g/l. In a 1 000 ml volumetric flask, dissolve 63,5 g of ultra-pure cesium chloride (CsCl) in water and fill up to the mark with water. NOTE This cesium solution is used
31、 to suppress ionization of calcium in a nitrous oxide/acetylene flame. The solution is not required when an air/acetylene flame or ICP technique is used. BS ISO 17812:200735 Apparatus and equipment 5.1 General Ordinary laboratory equipment is used. All glassware and plasticware shall be rinsed with
32、0,1 mol/l hydrochloric acid prior to use. 5.2 Filter paper, ash free, particle retention 20 m to 25 m. 5.3 Crucibles, platinum or fused silica, of minimum capacity 50 ml. NOTE If treatment with hydrofluoric acid is required, only platinum crucibles can be used, since fused silica is attacked by HF.
33、5.4 Muffle furnace, capable of maintaining a temperature of 525 C 25 C. 5.5 Balance, of capacity 100 g, accurate to 0,1 mg. 5.6 Atomic absorption spectrometer, equipped with air/acetylene and/or nitrous oxide/acetylene burners and with hollow cathode lamps for Mg, Ca, Mn, Fe and Cu. NOTE Multi-eleme
34、nt lamps can also be used. 5.7 Inductively coupled plasma (ICP) spectrometer. 5.8 Disposable protective gloves. 6 Sampling and preparation of sample If the analysis is being made to evaluate a lot of paper, board or pulp, the sample shall be selected in accordance with ISO 186 or ISO 7213, as releva
35、nt. If the analysis is made on another type of sample, report the source of the sample, and, if possible, the sampling procedure. Select the specimens so that they are representative of the sample received. A sufficient amount of sample shall be collected to allow for at least duplicate determinatio
36、ns. Avoid cut edges, punched holes and other parts where metallic contamination may have occurred. Protective disposable gloves (5.8) shall be worn when handling samples, to avoid contamination. Prepare a test specimen by tearing at least 30 g of small pieces from various parts of the sample. This a
37、mount is sufficient for the duplicate determinations as specified in Clause 7. Since iron tends to be nonhomogeneous in the sample, it is recommended that a composite sample be used. 7 Procedure 7.1 General Although dry ignition followed by acid treatment is described in this International Standard,
38、 other dissolution methods, such as wet ignition or microwave digestion using various acid combinations, can also be used, provided that the results have been validated. WARNING For samples with a high silicon content, microwave digestion with nitric acid will give lower results for magnesium and fo
39、r some other elements. 7.2 Incineration of the test portion Carry out the procedure in duplicate. Air-dry the specimen in the laboratory atmosphere until it reaches moisture equilibrium. BS ISO 17812:20074 Determine the moisture content on a separate air-dried portion as specified in ISO 287 or ISO
40、638, as relevant. Weigh this portion at the same time as the test portion used for incineration. For the determination of major elements, including magnesium and calcium, a 1 g to 2 g test portion (calculated as oven-dry) should be used. For minor elements, including manganese, iron and copper, test
41、 portions of 5 to 10 g should be used. If trace levels of elements are needed then use larger than 10 g sample sizes. Carry out ignition of the test portion as specified in ISO 1762. In order to avoid flames, the dish shall be covered with a lid. The lid shall only partially cover the dish to avoid
42、reducing conditions occurring in the dish, in which case acid-insoluble compounds may be formed. Under reducing conditions, for example, copper may be lost due to the formation of a platinum alloy. 7.3 Dissolution of the residue 7.3.1 General After ignition, allow the crucible to cool. To avoid spla
43、ttering, carefully moisten the residue of ignition with water and add cautiously, in a fume hood, 5 ml of hydrochloric acid (4.2) to the crucible. Evaporate to dryness on a boiling-water bath, hotplate or infrared lamp. Repeat this procedure. NOTE For samples with a high carbonate content, more than
44、 10 ml of acid (2 5 ml) might be needed. Add 5 ml of hydrochloric acid (4.2) to the residue. If some insoluble residue is visible, heat, without boiling, the crucible covered with a watch glass for a few minutes. If there is no insoluble residue after this treatment, add another 5 ml of hydrochloric
45、 acid (4.2), transfer quantitatively with water to a 100 ml volumetric flask. Dilute to 100 ml. If the sample contains insoluble material, two alternative procedures are described in 7.3.2 and 7.3.3. 7.3.2 Dissolution of the insoluble residue using hydrofluoric acid CAUTION Hydrofluoric acid is extr
46、emely irritating. It is readily absorbed through the skin, penetrating it to attack underlying tissues and bone. Disposable protective gloves shall be worn when handling this material to avoid all contact with exposed skin. Use only in a fumehood with adequate ventilation. Filter off the residue rem
47、aining after the hydrochloric acid treatment through the filter paper (5.2) retaining the filtrate in the 100 ml flask. After drying, ash the residue in a platinum crucible (5.3) at 525 C 25 C. Cool and add between 2 drops and 3 drops of sulfuric acid (4.4), followed by 5 ml of hydrofluoric acid (4.
48、3). Heat in a fumehood on a hotplate at a medium setting until all the hydrofluoric acid is evaporated, as indicated by the appearance of white fumes of sulfuric acid. Continue heating for an additional 5 min, then add 5 ml of hydrochloric acid (4.2) and combine it with the filtrate in the 100 ml vo
49、lumetric flask. Dilute to 100 ml. If some insoluble material remains after addition of hydrochloric acid, the procedure shall be repeated. If the sample also contains titanium, this will remain insoluble after the hydrofluoric acid treatment and shall be removed by filtration through the filter paper (5.2). 7.3.3 Dissolution of the insoluble residue by sodium carbonate/boric acid fusion Filter off the residue remaining after the hydrochloric acid treatment through the filter paper (5.2), retaining the filtrate in the 100
