ASTM_D_4893_-_94_2015e1.pdf

Designation:D489394(Reapproved 2015)1Standard Test Method forDetermination of Pitch Volatility1This standard is issued under the fixed designation D4893;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.1NOTESI units formatting was corrected editorially in May 2015.1.Scope1.1 This test method covers the determination of the percentof pitch volatility.1.2 Since this test method is empirical,strict adherence tothe procedure is necessary.1.3 The values stated in SI units are to be regarded as thestandard.The values in parentheses are given for informationonly.1.3.1 ExceptionsThe diameter of a special aluminumblock is measured in inches.1.4 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.Summary of Test Method2.1 An aluminum weighing dish with about 15 g of speci-men is introduced into the cavity of a metal block heated andmaintained at 350 C(662 F).After 30 min 6 10 s duringwhich the volatiles are swept away from the surface of theliquid pitch by preheated nitrogen,the sample is taken out andallowed to cool down in the desiccator.The pitch volatility isdetermined by the sample weight loss and reported as percentweight loss.3.Significance and Use3.1 This test is useful in evaluating and characterizing pitchphysical properties in comparing the consistency of shipmentsand sources of supply.4.Apparatus4.1 Aluminum Block,2412in.outside diameter,composed oftwo sections(Figs.1-4).4.1.1 The top block is maintained at a chosen constanttemperature according to the signal from the thermocoupleinserted into the thermowell No.1 near the center of the block.A proportional temperature controller regulates the heat input.Two insulated handles are attached to this part for easyhandling.An additional thermowell No.2,located in the centerof the block,accommodates another thermocouple used onlyfor the determination of the rate of temperature rise of thepitch.When the screw at the bottom of the No.2 well is takenout,the thermocouple can then be pushed down and inserted inpitch.4.1.2 The bottom block has a cavity for the aluminumweighing dish.Aspiral channel cut around the periphery of thispart serves for preheating the nitrogen introduced at themeasured rate(10 cm3/min)into the block for purging vola-tiles.4.1.3 The test temperature,the same as that in the top block,is maintained by the second proportional temperature control-ler according to the signals of a thermocouple inserted in athermowell No.3 of the bottom block.There is a hole in thecenter of the bottom cylinder to accommodate the sampleplatform,a rod with a stainless steel disk welded to its top.Thealuminum sample dish containing the sample rests on top ofthis disk during the test.The aluminum sample dish can belifted out of the cavity by raising the disk up to the upper rimof the cavity.4.2 Aluminum Weighing Dish.4.3 Flowmeter,0 cm3/min to 25 cm3/min range.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.05 on Properties of Fuels,Petroleum Coke and Carbon Material.Current edition approved April 1,2015.Published May 2015.Originallyapproved in 1989.Last previous edition approved in 2009 as D4893 94(2009).DOI:10.1520/D4893-94R15E01.2An aluminum block that may be obtained on special order from KoppersCompany,Inc.,1005 Wm.Pitt Way,Pittsburgh,PA 15238,has been foundsatisfactory for this purpose;or drawings of block will be furnished by Koppersupon request.If you are aware of alternative suppliers,please provide thisinformation to ASTM International Headquarters.Your comments will receivecareful consideration at a meeting of the responsible technical committee,1whichyou may attend.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.4 Nitrogen Cylinder,equipped with a pressure regulator.4.5 Timer,with an alarm.4.6 Aluminum Plate,127 mm by 127 mm,approximately20-gauge.5.Dehydration of Sample5.1 Hard PitchIf the solid bulk sample contains freewater,air-dry a representative portion in a forced-draft oven at50 C(122 F).5.2 Soft Pitch(Softening Point 60 C(140 F)If thepresence of water is indicated by surface foam on heating,maintain a representative portion of the bulk sample at atemperature between 125 C and 150 C(251 F and 302 F)in an open container until the surface is free of foam.Take carenot to overheat,and remove heat source immediately whenfoam subsides.6.Preparation of Working Sample6.1 Crush sample to pass No.4 mesh(4760 m).7.Prepar