ASTM_D_5655_-_95_2000.pdf

Designation:D 5655 95(Reapproved 2000)Standard Test Method forAnalysis of Copper Dimethyldithiocarbamate(CDDC)Treated Wood by Colorimetry 11This standard is issued under the fixed designation D 5655;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(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers colorimetric analysis of CDDCin treated wood.1.2 The values stated in SI units are to be regarded as thestandard.The inch-pound units given in parentheses are forinformation 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:D 147 Methods of Testing Bituminous Mastics,Grouts,andLike Mixtures22.2AWPA Standards:A10 Methods of Analysis of CCA Treating Solutions andCCA Treated Wood by Colorimetry3M2 Method for Sampling Wood3P5-14 Method of Analysis of Copper Dimethyldithiocar-bamate(CDDC)Treated Wood by Colorimetry32.3AOAC International Standard:Method 972.29 Spectrophotometric MethodThiram andThiram Residues43.Summary of Test Method3.1 Wood treated with CDDC is ground and extracted withchloroform/methanol azeotrope.CDDC,a colored compound,is determined colorimetrically by use of a suitable spectropho-tometer at a wavelength of 435 nm.4.Significance and Use4.1 Copper dimethyldithiocarbamate(CDDC)for use in thepreservative treatment of wood must conform with this testmethod.5.Apparatus5.1 SpectrophotometerAny good spectrophotometer canbe used.55.2 Heated Magnetic Stir Plate.5.3 Increment Borer and GrinderA typical Wiley mill issuitable to grind samples.The device should be capable ofreducing the wood to a small particle size(30 mesh).5.4 Reflux Apparatus,(Methods D 147,or equivalent).5.5 Buchner Vacuum Filter/Flask.55.6 Laboratory Glassware,volumetric flasks,pipettes,cu-vettes,and other commonly available glassware.5.7 Filter Paper,Whatman#425(sized to fit BuchnerFunnel).6.Reagents6.1 Chloroform,Spectro Grade CH3Cl.6.2 Copper Dimethyldithiocarbamate,analytical standard99%.66.3 Methyl Alcohol,Spectro Grade CH3OH.6.4 Extraction Azeotrope,12.6%MeOH/87.4%CH3Cl(w/w).7.Sampling7.1 Sample treated wood as described in Paragraph 5 ofAWPAStandard M 2 except that the increment borings must beoven dried(60C or less).8.Preparation of CDDC Standards8.1 Produce a standard curve by dissolving analytical gradecopper dimethyldithiocarbamate in azeotrope to produce1This test method is under the jurisdiction of ASTM Committee D-7 on Woodand is the direct responsibility of Subcommittee D07.06 on Treatments for WoodProducts.Current edition approved Jan.15,1995.Published March 1995.2Discontinued;see 1988 Annual Book of ASTM Standards,Vol 04.04.3Available from the American Wood-Preservers Association,P.O.Box 286,Woodstock,MD 21163.4Available from theAssociation of OfficialAnalytical Chemists,Suite 400,2200Wilson Blvd.,Arlington,VA 22201-3301.5Use a visual spectrophotometer,such as Beckman Model,35,B/L Spectronic20,or equivalent.Available from Fisher Scientific,Box 405,Pittsburgh,PA 15230;or CMS,P.O.Box 98944,Chicago,IL 60693.6Available from Pflatz and Bauer,P.O.Box 3723,New Hyde Park,NY 11040.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.known amounts of CDDC in the range from 0 to 25 ppm.Plotthese known,weighed,prepared standards against the absor-bance measured by the spectrophotometer at a wavelength of435 nm on standard quadrille graph paper.9.Procedure9.1 When using 20 borings(0.6 in.(15.24 mm)in length(approximately 3.2 g of wood)use 200 g of chloroformazeotrope for extraction.9.2 Preparation of Standard Graph for CDDC in TreatedWood:9.2.1 Place analytical grade CDDC standard in azeotrope indosage range from 3.55 to 21.31 g/mL CDDC.Read in thespectrophotometer at 435 nm against chloroform/methanolazeotrope as the reference.The absorbance found will be 0.08to 1.00.Plot the data for microgram per millilitre(or alterna-tively kilogram per cubic metre CDDC)against absorbance.Determine linearity and best fit for the respective curve.9.3 Testing Borings from Treated Wood:9.3.1 Grind whole borings prior to analysis.For this extrac-tion technique,it is necessary to use an azeotrope,that has thecapability of swelling the wood,to assist in extraction effi-ciency.Use an azeotrope consisting of 87.4%chloroform,12.6%methanol.9.3.2 Place ground borings into the extraction flask.9.3.3 Place 200.0 mL of azeotrope into extraction flask.9.3.4 Heat the extraction flask to 45C and allow influx tocycle several times over a 30-min period.9.3.5 After cooling,filter sawdust and extraction solventconta