BS ISO 699-2015 Pulps Determination of alkali resistance《纸浆 耐碱性的测定》.pdf

1、BSI Standards PublicationBS ISO 699:2015Pulps Determination ofalkali resistanceBS ISO 699:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 699:2015. Itsupersedes BS 4499:1984 which is withdrawn.The UK participation in its preparation was entrusted to Techni

2、calCommittee PAI/11, Methods of test for paper, board and pulps.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. T

3、he British Standards Institution 2015. Published by BSI StandardsLimited 2015ISBN 978 0 580 86893 1ICS 85.040Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 30 Apr

4、il 2015.Amendments issued since publicationDate Text affectedBS ISO 699:2015 ISO 2015Pulps Determination of alkali resistancePtes Dtermination de la rsistance aux solutions dhydroxyde de sodiumINTERNATIONAL STANDARDISO699Third edition2015-04-01Reference numberISO 699:2015(E)BS ISO 699:2015ISO 699:20

5、15(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2015All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or a

6、n intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPub

7、lished in SwitzerlandBS ISO 699:2015ISO 699:2015(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13 Terms and definitions . 14 Principle 15 Reagents 16 Apparatus . 27 Preparation of the test sample . 28 Procedure. 38.1 Test portion 38.2 Determination . 39 Expression of results 49.1 Meth

8、od of calculation and formula . 49.2 Precision and expression of results 410 Test report . 4Bibliography 5 ISO 2015 All rights reserved iiiContents PageBS ISO 699:2015ISO 699:2015(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodie

9、s (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations,

10、 governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further ma

11、intenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).At

12、tention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduct

13、ion and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to confor

14、mity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT), see the following URL: Foreword Supplementary information .The committee responsible for this document is ISO/TC 6, Paper, board and pulps.This third edition cancels and repla

15、ces the second edition (ISO 699:1982), of which it constitutes a minor revision.iv ISO 2015 All rights reservedBS ISO 699:2015ISO 699:2015(E)IntroductionThe object of both this International Standard and ISO 692, Pulps Determination of alkali solubility, is to permit the study of the behaviour of pu

16、lps in the presence of alkali solutions, but their fields of application are different. While this International Standard describes the gravimetric determination of the alkali insoluble constituents of the pulp and applies to all categories of pulps, ISO 692 describes the volumetric determination of

17、 the alkali soluble constituents of the pulp and is applied preferably to the control of bleached pulps. ISO 2015 All rights reserved vBS ISO 699:2015BS ISO 699:2015Pulps Determination of alkali resistanceWARNING The method specified in this International Standard involves the use of hazardous chemi

18、cals. Appropriate precautions are to be taken to ensure the proper use and disposal of these chemicals.1 ScopeThis International Standard specifies a method for the determination of the alkali-insoluble fraction of pulps using sodium hydroxide solution of fixed concentration. The sodium hydroxide co

19、ncentrations most frequently used are 18, 10, and 5 % (m/m).The method is applicable to all kinds of pulp.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition

20、cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 638, Paper, board and pulps Determination of dry matter content Oven-drying methodISO 4793, Laboratory sintered (fritted) filters Porosity grading, classification and designati

21、on3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1R-valuealkali resistance; the insoluble fraction expressed as a percentage by mass of the oven-dry pulp3.2R18, R10, R5, or RcR-values in which the indices 18, 10, 5, or c refer to the chosen conc

22、entration in grams of sodium hydroxide per 100 g of solution4 PrincipleDefibreing of the pulp under specified conditions in sodium hydroxide solution of chosen concentration.Filtering of the insoluble fraction, washing with sodium hydroxide solution of the same concentration, and temperature as that

23、 used for defibreing and acidification, washing, drying, and weighing.5 ReagentsUse only reagents of recognized analytical grade and only distilled water or water of equivalent purity.5.1 Sodium hydroxide, solution of known concentration containing less than 1 g of sodium carbonate per litre (see th

24、e notes), for example: (5,39 0,03) mol/l solution, containing (18,0 0,1) g of sodium hydroxide per 100 g of solution (20= 1,197 2 g/ml), equivalent to (215,5 1,0) g of sodium hydroxide per litre;INTERNATIONAL STANDARD ISO 699:2015(E) ISO 2015 All rights reserved 1BS ISO 699:2015ISO 699:2015(E) (2,77

25、 0,03) mol/l solution, containing (10,0 0,1) g of sodium hydroxide per 100 g of solution (20= 1,108 9 g/ml), equivalent to (110,9 1,0) g of sodium hydroxide per litre; (1,31 0,03) mol/l solution, containing (5,0 0,1) g of sodium hydroxide per 100 g of solution (20= 1,053 8 g/ml), equivalent to (52,7

26、 1,0) g of sodium hydroxide per litre.NOTE 1 The sodium hydroxide solution can be conveniently prepared as follows: dissolve a quantity of solid sodium hydroxide in an equal mass of water and allow the suspended sodium carbonate to settle. Decant the supernatant liquid and dilute with carbon dioxide

27、-free water to the appropriate concentration. Check by titration with standard acid solution.NOTE 2 Although sodium hydroxide solution generally possesses the maximum dissolving power at a concentration of about 10 % (m/m), certain pulps show maximum solubility at some lower or higher alkali concent

28、ration. If the R-value of an unknown pulp or of a new type of pulp is to be determined with the sodium hydroxide solution of maximum dissolving power for this pulp, it is necessary to establish a solubility diagram using several different concentrations in order to determine the sodium hydroxide con

29、centration of maximum dissolving power.5.2 Acetic acid, 1,7 mol/l solution, corresponding to 100 ml of CH3COOH (20= 1,055 to 1,058 g/ml) per litre.6 Apparatus6.1 Beaker, of capacity 250 ml, flat-bottomed, made of alkali-resistant material.6.2 Stirring rod, of diameter 15 mm, with a flat end, made of

30、 a non-brittle alkali-resistant material, preferably hard plastics.6.3 Filtering device, of capacity 80 to 100 ml, internal diameter about 30 mm, with a bottom made of sintered glass, of porosity grade P 250 (porosity 0) in accordance with ISO 4793.6.4 Weighing bottle, with a lid.6.5 Constant temper

31、ature bath, capable of maintaining a temperature of (20 0,2) C.7 Preparation of the test sampleIf the pulp is in slush form, remove the water by suction taking precautions to avoid the loss of fine fibres, press between blotters, and dry at a maximum temperature of 60 C.If the pulp is in the form of

32、 wet sheets or rolls, dry the sample at a maximum temperature of 60 C.Tear the sample into pieces of size approximately 5 mm x 5 mm. If the pulp is difficult to defibre, split the sample by means of tweezers (see Note 1).Check that the pulp contains not more than 0,1 % ash (see Note 2). Before weigh

33、ing, condition, the sample for not less than 20 min in the atmosphere near the balance.NOTE 1 Dry disintegration, for example with a Wiley-mill, or wet disintegration, for example with a high-speed stirrer, are not permitted.NOTE 2 If the pulp to be tested contains more than 0,1 % ash, determine the

34、 ash content of the alkali-insoluble fraction. Calculate the R-value on the basis of the ash-free pulp and the ash-free insoluble fraction.2 ISO 2015 All rights reservedBS ISO 699:2015ISO 699:2015(E)8 Procedure8.1 Test portionWeigh, to the nearest 1 mg, about 2,5 g of the test sample. Then immediate

35、ly weigh two separate test portions for the determination of the dry matter content in accordance with ISO 638.8.2 DeterminationTransfer the test portion to the beaker (6.1), add 25 ml of the sodium hydroxide solution (5.1) adjusted to (20 0,2) C (see 5.1, Note 1 and Note 2), place the beaker in the

36、 constant temperature bath (6.5), and allow the pulp to swell for 3 min.Thoroughly defibre the pulp by stirring and macerating with the stirring rod (6.2) for at least 3 min, macerating at a rate of two strokes per second. Add another 25 ml of the sodium hydroxide solution at 20 C, stir until the su

37、spension is uniform, and dilute by adding 100 ml of the sodium hydroxide solution at 20 C. Cover the beaker with a watch-glass and leave in the constant temperature bath.60 minutes after the first addition of the sodium hydroxide solution, stir the fibre suspension again and transfer it to the filte

38、ring device (6.3) fitted on a dry suction flask, adjusted to a temperature of (20 0,2) C in the constant temperature bath.Apply suction only as long as the fibre mat is still covered with liquid in order that no air is sucked through the mat. Use the filtrate for rinsing the beaker and filter again

39、through the slightly pressed fibre mat in order to collect all fibres. Finally, apply full suction briefly. The time for filtering and washing shall not exceed 20 min.Compact the fibre mat, especially at the edges, cover with the acetic acid (5.2) and allow 200 ml to pass through slowly without suct

40、ion. Drain completely and wash with hot water until the filtrate is free from acid.Cover the filtering device with the hand during the last washing in order that a vacuum is formed above the fibre mat. Then quickly release the vacuum in the suction flask in order to lift the fibre mat. Transfer the

41、fibre mat together with any remaining fibres adhering to the filtering device by means of stainless steel tweezers to the weighing bottle (6.4).Place the open weighing bottle together with its lid in a drying oven and dry to constant mass at a temperature of (105 2) C (normally for 6 h). Allow the c

42、losed weighing bottle to cool in a desiccator and determine the mass of the alkali-insoluble fraction to the nearest 1 mg, after briefly raising the lid to allow equalization of pressure.Carry out at least two parallel determinations on each test sample.NOTE 1 In certain cases, for example, straw pu

43、lps, it is advisable to add initially only 15 ml or 20 ml of the sodium hydroxide solution to the pulp in order to facilitate defibreing. The volume of alkali for the second addition has then to be increased to 35 ml or 30 ml respectively.The solubility in 18 % (m/m) sodium hydroxide solution is not

44、 affected by variations of a few degrees in temperature. At this concentration, the temperature may be kept at (20 2) C.The solubility in sodium hydroxide solution of lower concentration (for example, 10 % (m/m) is much more dependent on temperature. At this lower concentration, the temperature shou

45、ld be kept at (20 0,2) C. ISO 2015 All rights reserved 3BS ISO 699:2015ISO 699:2015(E)9 Expression of results9.1 Method of calculation and formulaThe alkali resistance, Rc, expressed as a percentage by mass, is given by the formulamm10100(1)wherem0is the mass, in grams, of the test portion calculate

46、d on an oven-dry basis;m1is the oven-dry mass, in grams, of the alkali-insoluble fraction.9.2 Precision and expression of resultsThe results of the parallel determinations should agree to within 0,3 %.Report the mean alkali resistance to one decimal place using the symbols R18, R10, etc.NOTE For pul

47、ps containing less than 0,1 % ash, and other noncarbohydrate materials, the value (100 - Rc) approaches the value (Sc) determined by the method for alkali solubility of pulps described in ISO 692.10 Test reportThe test report shall include the following particulars:a) a reference to this Internation

48、al Standard, i.e. ISO 699;b) the results and the method of expression used;c) any unusual features noted during the determination;d) any operation not specified in this International Standard, or regarded as optional.4 ISO 2015 All rights reservedBS ISO 699:2015ISO 699:2015(E)Bibliography1 ISO 692,

49、Pulps Determination of alkali solubility ISO 2015 All rights reserved 5BS ISO 699:2015ISO 699:2015(E) ISO 2015 All rights reservedICS 85.040Price based on 5 pagesThis page deliberately left blankBSI is the national body responsible for preparing British Standards and other standards-related publications, information and services.BSI is incorporated by Royal Charter. British Standards and other standardization products are published by BSI Standards Limited.British Standards In