Document ZnqLrDkJLBD7D3GxK7eEB879J

l i,. / ?! ' ** * \ < - * <>. : a -* : - i -.v {-nV-j-sas.i . f) I DIRECTIONS FOR TEST HD* 01-44-41 SUBJECT: Color of "Lily White* Aroclora ,t tr-f ^ . MMEifTfiHaOmDit CuoommppaarrlisBoonn aagf ainst APH>A Scale .*. v i -* *'. Si1- r .'** _ gcopfam .. .................... . ^ :;i fPSfif:TheTi^hdd is' applicable to Aroblors 1254,'1260, 6'r others hav-- -7.: ing color loss than NPA* #1 ("Lily White") :'-'-, A*P*H*A Standards . These color standards are acid solutions of potassium chloro-* platinate and eohaltous ehloride* The unit of color is that produced by 1 mg* of platinum per liter* The ratio of cobalt to platinum may be TOried if necessary to match the hue* Because the hue of Aroclor 1254 and 1260 Seems best matched without cobalt, this.has been omitted in the preparation described*; .} Dissolve 1*245 g* of potassium ehloroplatinate (^PtCl) containring 0*5 g. of platinum in water with 100 ml* of concentrated hydro-- chloric acid, and dilute to 1 liter with distilled water* This solu tion has a color of 500* . __ Prepare standards from 10 to 100 in steps of 10 by diluting 1, ___ 2, 3 ml* etc* of the above solution with distilled water to 50 ml* in standard high form Kessler tubes* Protect the tubes from evaporation* Refer to page IS of standard ifethods for the Examination of Wa ter Sewage" eighth edition (1936) for details of standards contain-- ing cobalt* Published by American Public Health Association, 1790 - Broadway, New York* 1 Procedure ' ^ ^ ;V/... Pill a matching Nessler tube with Aroclor to a height equal to that in the standard tubes* Compare with standards by looking ver tically downward through the tubes upon a white or mirrored surface placed at such an angle that light is reflected upward through the column of liquid* .A.color tu^> support jFisher ^-065* 50 ml.) is. ; convenient* ......... .vV : , " Inasmuch as the propbrtions of the standard ddldr solution ia^`3 the comparison tubes are such as to represent an aliquot part of a v , liter, thereadings are direct as parts per million* Colors up to 100 are recorded to the nearest 5* Direct ccaparisons are satis factory up to 100* Above this the sample should be diluted with benzol (maximum A*P*H* color-5), end the color obtained -- to nearest 10 -- by multiplying by the dilution ratio* ABO-p 9/25/41 DS* 3JlW STLCOPCB4077366