ASTM_D_1512_-_15.pdf

Designation:D151215Standard Test Methods forCarbon BlackpH Value1This standard is issued under the fixed designation D1512;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 These test methods,Test MethodABoiling Slurry andTest Method BSonic Slurry,are used to indicate the pH ofthe carbon black surface by measuring the pH of water incontact with the carbon black.NOTE1The pH of the carbon black is often used in this industry toindicate the relative acidity or alkalinity of carbon black and will be usedin the remainder of these test methods to describe this property.NOTE2Test Method A and Test Method B do not always give thesame results.1.2 The values stated in SI units are to be regarded as thestandard.The values in parentheses are for information only.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD1799 Practice for Carbon BlackSampling PackagedShipmentsD1900 Practice for Carbon BlackSampling Bulk Ship-mentsD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustriesE70 Test Method for pH of Aqueous Solutions With theGlass Electrode3.Significance and Use3.1 The pH level of a carbon black is known to affect thevulcanization of some rubber compounds.TEST METHOD ABOILING SLURRY4.Apparatus4.1 pH Meter,(digital is recommended)having an accuracyof 60.05 pH and equipped with a combination electrode andRNC connector.4.2 Container,stainless steel or copper,125 cm3or larger.4.3 Hot Plate.4.4 High Speed Mill,Mixer or Mortar and Pestle.4.5 Beakers,glass,100 cm3graduated with watch glasses.5.Reagents5.1 Purity of ReagentsReagent grade chemicals shall beused in all tests.Unless otherwise indicated,it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.3Other grades may beused,provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.5.2 Purity of WaterUnless otherwise indicated,referencesto water shall be understood to mean reagent water as definedby Type 1 in Specification D1193.5.3 Distilled Water,high purity.5.4 Buffer Solutions,pH of 4.00,7.00,and 10.00.5.5 Acetone,reagent grade.6.Sampling6.1 Samples shall be taken in accordance with PracticesD1799 or D1900.7.Calibration7.1 Calibrate the pH meter using buffer solutions accordingto manufacturers instructions.1These test methods are under the jurisdiction of ASTM Committee D24 onCarbon Black and are the direct responsibility of Subcommittee D24.31 onNon-Carbon Black Components of Carbon Black.Current edition approved Jan.1,2015.Published February 2015.Originallyapproved in 1975.Last previous edition approved in 2012 as D1512 05(2012).DOI:10.1520/D1512-15.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Reagent Chemicals,American Chemical Society Specifications,AmericanChemical Society,Washington,DC.For suggestions on the testing of reagents notlisted by the American Chemical Society,see Analar Standards for LaboratoryChemicals,BDH Ltd.,Poole,Dorset,U.K.,and the United States Pharmacopeiaand National Formulary,U.S.Pharmacopeial Convention,Inc.(USPC),Rockville,MD.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 8.Procedure8.1 Pulverize pelleted or lumpy carbon black to a finepowder,using either the high speed mixer or mortar and pestle.8.2 Weigh 5 g of carbon black into a 100 cm3glass beaker.8.3 Add 50 cm3of boiling,distilled water prepared in astainless steel beaker and 2 to 3 drops of acetone to facilitatewetting of the sample.NOTE3A stainless steel beaker is used to eliminate contaminationduring boiling.8.4 Cover the glass beaker with a watch glass and boil themixture for 15 min,but do not allow all the liquid to evaporate.8.5 Let the mixture cool to room temperature in an atmo-sphere free from chemical fumes which might contaminate thesample.8.6 Standardize the pH meter with the buffer solutions.Rinse the electrode with distilled water and wipe clean aftereach test.8.7 Place a magnetic stir bar into the glass beak