BS EN 1484-1997 Water analysis - Guidelines for the determination of total organic carbon (TOC) and dissolved organic carbon (DOC)《水分析 有机碳(TOC)和溶解的有机碳(DOC)总含量的测定导则》.pdf

1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 1484 : 1997 The Eur

2、opean Standard EN 1484 : 1997 has the status of a British Standard ICS 13.060.01 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Water analysis Guidelines for the determination of total organic carbon (TOC) and dissolved organic carbon (DOC)This British Standard, having been p

3、repared under the direction of the Health and Environment Sector Board, was published under the authority of the Standards Board and comes into effect on 15 October 1997 BSI 1997 ISBN 0 580 28372 0 BS EN 1484 : 1997 Amendments issued since publication Amd. No. Date Text affected National foreword Th

4、is British Standard is the English language version of EN 1484 : 1997. The UK participation in its preparation was entrusted to Technical Committee EH/3/2, Physical chemical and biochemical methods, which has the responsibility to: aid enquirers to understand the text; present to the responsible Eur

5、opean committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary.

6、Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled International Standards Correspondence Index, or by using the Find facility of the BSI Standards Electroni

7、c Catalogue. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 10, an inside back cover and a back cover.CEN European Committee for Standardization

8、 Comite Europe en de Normalisation Europa isches Komitee fu r Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1997 CEN - All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 1484 : 1997 E EUROPEAN STANDARD EN 1484 NORME EUR

9、OPE ENNE EUROPA ISCHE NORM May 1997 ICS 13.060.30 Descriptors: Environmental protection, water tests, potable water, ground water, sea water, surface water, sewage, chemical analysis, determination of content, organic carbon English version Water analysis Guidelines for the determination of total or

10、ganic carbon (TOC) and dissolved organic carbon (DOC) Analyse de leau Lignes directrices pour le dosage du carbone organique total (TOC) et carbone organique dissous (COD) Wasseranalytik Anleitungen zur Bestimmung des gesamten organischen Kohlenstoffs (TOC) und des gelo sten organischen Kohlenstoffs

11、 (DOC) This European Standard was approved by CEN on 1997-04-06. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical r

12、eferences concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN membe

13、r into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portug

14、al, Spain, Sweden, Switzerland and United Kingdom.Page 2 EN 1484 : 1997 BSI 1997 Foreword This European Standard has been prepared by the Technical Committee CEN/TC 230, Water analysis, the secretariat of which is held by DIN. This European Standard contains three informative annexes. This European

15、Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by November 1997, and conflicting national standards shall be withdrawn at the latest by November 1997. According to the CEN/CENELEC Internal Regulations, the nation

16、al standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom.Page

17、 3 EN 1484 : 1997 BSI 1997 Introduction It is absolutely essential that tests conducted according to this standard are carried out by suitably qualified staff. Total organic carbon (TOC) is a measure of the carbon content of dissolved and undissolved organic matter present in the water. It does not

18、give information on the nature of the organic substance. 1 Scope This European Standard gives guidance for the determination of organic carbon in drinking water, ground water, surface water, sea water and waste water. It deals with definitions, interferences, reagents, and the sample pretreatment of

19、 water samples with a content of organic carbon ranging from 0,3 mg/l to 1000 mg/l while the lower value is only applicable in special cases, for example drinking water, measured with instruments capable of measuring these low levels. Higher concentrations may be determined after appropriate dilutio

20、n. This European Standard does not deal with the instrument-dependent aspects. In addition to organic carbon, the water sample may contain carbon dioxide or ions of carbonic acid. Prior to the TOC determination, it is essential that this inorganic carbon is removed by purging the acidified sample wi

21、th a gas which is free from CO 2 and organic compounds. Alternatively, both total carbon (TC) and total inorganic carbon (TIC) may be determined and the organic carbon content (TOC) may be calculated by subtracting the total inorganic carbon from the TC. This method is particularly suitable for samp

22、les in which the total inorganic carbon is less than the TOC. Purgeable organic substances, such as benzene, toluene, cyclohexane, and chloroform may partly escape upon stripping. In the presence of these substances, the TOC concentration is determined separately, or the differential method (TC2 TIC

23、 = TOC) may be applied. By using the differential method, the value of the TOC should be higher than the TIC, or at least of similar size. Cyanide, cyanate, and particles of elemental carbon (soot) when present in the sample, will be determined together with the organic carbon. NOTE. In the presence

24、 of humic material, low values may occur when UV radiation is used. 2 Normative references This European Standard incorporates by dated or undated reference provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed

25、hereafter. For dated reference, subsequent amendment to or revisions of any of these publications apply to this European standard only when incorporated in it by amendment or revision. For undated reference the latest edition of the publication referred to applies. EN ISO 5667-3 : 1995 Water quality

26、 Sampling Part 3: Guidance on the preservation and handling of samples (ISO 5667-3 : 1994) 3 Definitions For the purposes of this European Standard the following definitions apply. 3.1 total carbon (TC) The sum of organically bound and inorganically bound carbon present in water, including elemental

27、 carbon. 3.2 total inorganic carbon (TIC) The sum of carbon present in water, consisting of elemental carbon, total carbon dioxide, carbon monoxide, cyanide, cyanate, and thiocyanate. TOC instruments mostly register as TIC only the CO 2 originating from hydrogen carbonates and carbonates. 3.3 total

28、organic carbon (TOC) The sum of organically bound carbon present in water, bonded to dissolved or suspended matter. Cyanate, elemental carbon and thiocyanate will also be measured. 3.4 dissolved organic carbon (DOC) The sum of organically bound carbon present in water originating from compounds whic

29、h will pass a membrane filter of pore size of 0,45mm. Cyanate and thiocyanate are also measured. 3.5 volatile organic carbon (VOC, POC) Under the conditions of this method, purgeable organic carbon (POC). 3.6 non volatile organic carbon (NVOC, NPOC) Under the conditions of this method, non-purgeable

30、 organic carbon (NPOC).Page 4 EN 1484 : 1997 BSI 1997 4 Principle Oxidation of organic carbon (org. C) in water to carbon dioxide by combustion, by the addition of an appropriate oxidant, by UV radiation or any other high energy radiation. The application of the ultraviolet method with only oxygen a

31、s an oxidant is restricted to low polluted waters, containing low concentrations of TOC. Inorganic carbon is removed by acidification and purging, or is determined separately. The carbon dioxide formed by oxidation is determined either directly or after reduction, for example, to methane (CH 4 ). Th

32、e final determination of CO 2 is carried out by a number of different procedures, for example: infrared spectrometry, titration (preferably in non-aqueous solution), thermal conductivity, conductometry, coulometry, CO 2 - sensitive sensors and flame ionization detection; used after reduction of the

33、CO 2 , among others, to methane. 5 Reagents 5.1 General remarks Use only reagents of recognized analytical grade. In this European Standard, only those chemicals and gases are listed which are used with the majority of TOC methods. Reagents should be used according to the manufacturers instructions,

34、 and should be pretreated, if necessary. The TOC of the water being used for dilution and for preparation of the calibration standards should be negligibly low, compared with the lowest TOC concentration to be determined. The method for water treatment depends on the concentration range under invest

35、igation as shown in table 1. NOTE. For measurements of a TOC concentration 100 1 Distillation * Only for ultra pure water. 5.2 Potassium hydrogen phthalate, stock solution, r(org. C) = 1 000 mg/l Dissolve in a 1 000 ml one-mark volumetric flask 2,125 g of potassium hydrogen phthalate (C 8 H 5 KO 4 )

36、 (dried for 1 h at a temperature of between 105C and 120C) in 700 ml of water, and make up to volume with water. The solution is stable for about 2 months if stored in a tightly stoppered bottle in a refrigerator. 5.3 Potassium hydrogen phthalate, standard solution, r(org. C) = 100 mg/l Pipette 100

37、ml of the potassium hydrogen phthalate stock solution (5.2) into a 1 000 ml one-mark volumetric flask, and make up to volume with water. The solution is stable for about 1 week if stored in a tightly stoppered bottle in a refrigerator. 5.4 Standard solution for the determination of inorganic carbon,

38、 r(inorg. C) = 1 000 mg/l Dissolve in a 1 000 ml one-mark volumetric flask 4,415 g of sodium carbonate (Na 2 CO 3 ), dried for 1 h at (285 5) C in approximately 500 ml of water. Add 3,500 g of sodium hydrogen carbonate (NaHCO 3 ) (dried for 2 h over silica gel), and make up to volume with water. Thi

39、s solution is stable at room temperature for about 2 weeks. 5.5 Substances, not readily oxidizable A standard solution shall be used to check the operational performance of the system. NOTE. In the interlaboratory trial, copper phthalocyanine has been used for this purpose. A suitable test solution

40、of copper phthalocyanine, r(org. C) = 100 mg/l, may be prepared as follows: In a 1 000 ml volumetric flask 0,256 g of copper phthalocyanine- tetrasulfonic acid (tetrasodium salt) (C 32 H 12 CuN 8 O 12 S 4 Na 4 ) are dissolved in 700 ml of water, and made up to volume with water. The solution is stab

41、le for about 2 weeks. WARNING: This reagent is toxic. 5.6 Further reagents 5.6.1 The reagents 5.2, 5.4 and 5.5 may be replaced by other reagents provided these are stable titrimetric substances. 5.6.2 Non volatile acids for expelling the carbon dioxide, such as phosphoric acid, c(H 3 PO 4 ) = 0,5 mo

42、l/l, if necessary, more concentrated. 5.7 Gases Air, nitrogen, oxygen, free from carbon dioxide and organic impurities. Use other gases in accordance with the instrument manufacturers specifications.Page 5 EN 1484 : 1997 BSI 1997 6 Apparatus Usual laboratory apparatus and: 6.1 Apparatus for the dete

43、rmination of organic carbon. 6.2 Homogenization device, for example a magnetic stirrer with adequate performance for the homogenization of dispersed matter, a suitable ultrasonic apparatus or a high speed stirrer. 7 Sampling and samples 7.1 Sampling See also EN ISO 5667-3. When sampling, ensure that

44、 the samples being collected are representative (particularly in the presence of undissolved substances), and take care not to contaminate the samples with organic substances. Collect water samples in glass or polyethylene bottles, completely filled with the sample, and, if biological activity is su

45、spected, acidify to pH 2 (for example with phosphoric acid, 5.6.2). In some cases, the result may be reduced by the loss of volatile substances due to the liberation of carbon dioxide when the sample is acidified. If volatile organic compounds are suspected, carry out the measurement without acidifi

46、cation and within 8 h of sampling. Otherwise, store the sample in a refrigerator at a temperature in the range of 2 C to 5 C, and analyse within 7 days. If this is not possible, the sample can be kept at215 C to220 C for up to several weeks. 7.2 Preparation of the water sample If, because of inhomog

47、eneity, the collection of a representative sample is not possible, even after thorough shaking, homogenize the sample, using for example, the apparatus as described in 6.2. The homogeneity may be checked, for example, by analysing a sample from the upper and the lower layer of the bottle. If only di

48、ssolved organic substances (DOC) are to be determined, filter the sample through a membrane filter, pore size 0,45mm, which has previously been washed with hot water to completely remove adhering organic substances. Nevertheless the carbon content of the filtrate has to be determined and taken into

49、account. 8 Procedure 8.1 Calibration Comparison methods (for example IR detection) require calibration; in the case of absolute methods, for example acidimetry or coulometry, the calibration serves the purpose of checking the analytical system. Calibrate the instrument according to the manufacturers instructions. Establish a calibration curve by analysing potassium hydrogen phthalate standard solutions of adequate concentrations. For example for mass concentrations ranging from 10 mg/l to 100 mg/l proceed as follows. Prepare a series o