ASTM_D_6288_-_15.pdf

Designation:D628815Standard Practice forSeparation and Washing of Recycled Plastics Prior toTesting1This standard is issued under the fixed designation D6288;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.1.Scope*1.1 This practice describes a procedure for separating re-cycled plastics based on their color and a procedure forwashing dirty,ground plastic,which results in separation oflight materials(density 1.00 g/cm3).This practice is notintended to represent generic washing procedures used in theplastics recycling industry.The described procedures are solelyfor preparation of plastic samples for use in other analyticaltests.The procedure includes a room temperature wash step tofacilitate separation of paper(for example,labels)followed bywashing at an elevated temperature.NOTE1Although not presented as a quantitative method,the proce-dure presented in this practice may be used to provide quantitative results.The user assumes the responsibility to verify the reproducibility ofquantitative results.1.2 The values stated in SI units are to be regarded as thestandard.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.NOTE2There is no known ISO equivalent to this standard.2.Referenced Documents2.1 ASTM Standards:2D1600 Terminology forAbbreviated Terms Relating to Plas-ticsD5814 Practice for Determination of Contamination in Re-cycled Poly(Ethylene Terephthalate)(PET)Flakes andChips Using a Plaque TestD5991 Practice for Separation and Identification of Poly(Vi-nyl Chloride)(PVC)Contamination in Poly(EthyleneTerephthalate)(PET)FlakeD7209 Guide for Waste Reduction,Resource Recovery,andUse of Recycled Polymeric Materials and Products(With-drawn 2015)3IEEE/ASTM SI-10 Standard for Use of the InternationalSystem of Units(SI):The Modern Metric System3.Terminology3.1 The terminology used in this practice is in accordancewith Terminology D1600 and Guide D7209.Units and symbolsare in accordance with Standard IEEE/ASTM SI-10.3.2 Definitions of Terms Specific to This Standard:3.2.1 light materialmaterials with densities less than 1.00g/cm3.4.Summary4.1 Different colored plastic materials are readily distin-guished by visual inspection of a sample.4.2 Labels,glue residues and other plastics may absorb thedyes used in some procedures for identifying contaminants orthese other contaminants may exhibit interfering fluorescence.Consequently,a standard procedure is provided for washingthe plastic prior to examination by these tests.4.3 This practice utilizes a room temperature wash step tofacilitate separation of paper followed by washing at anelevated temperature to permit separation of plastics and othercontaminants based on densities.The room temperature washstep effectively removes labels without activating some adhe-sives.NOTE3The dye and fluorescence tests that may require plasticwashed by this procedure are specifically designed to detect poly(vinylchloride)(PVC)contamination.4.4 Washed recycled plastic materials are then used for testssuch as those described in Practices D5814 or D5991.5.Significance and Use5.1 Dirt,paper and mixtures of polymeric materials com-plicate the interpretation of data from procedures used toidentify the contaminants in recycled plastics.1This practice is under the jurisdiction ofASTM Committee D20 on Plastics andis the direct responsibility of Subcommittee D20.95 on Recycled Plastics.Current edition approved Oct.1,2015.Published October 2015.Originallyapproved in 1998.Last previous edition approved in 2009 as D6288-09.DOI:10.1520/D6288-15.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.Apparatus6.1 Bright Aluminum Tray,shallow depth(750 mm),withminimum area of 774 cm2(120 in.2).6.2 Balances,suitable for weighing 500 g of flake.6.3 Baffled Beaker,stainless steel,15.2 cm(6 in.)diameterwith four 1.9 cm(0.75 in.)baffles providing a slurry height/diameter ratio of 0.9.6.4 Cover for Beaker(see 6.3)which can accommodate athermometer(or other temperature sensing device)and thestirring impeller rod.6.5 Overhead Stirrer,capable of 1000 r/min.6.6 Stirring Impeller,pitched three blade,7.62 cm(3 in.)dia