PDF Publication Title:
Text from PDF Page: 114
ARSENIC Method 206.5 (Sample Digestion Prior to Total Arsenic Analysis by Silver Diethyldithiocarbamate or Hydride Procedures) 1 Scope and ApphcatlOn 1 1 Both the sIlver diethyldithlOcarbamate spectrophotometnc method and the AA hydnde procedure measure morgamc arsemc Therefore, If eIther of these procedures are bemg employed for the purpose of measunng total arsemc (morgamc plus orgamc), all orgamcally bound arsemc must first be converted to an morgamc form pnor to the analytIcal determmatlOn ThIS may be accomphshed WIth H2S04-HN03 2 Procedure 21 ToaSUItablesamplecontammgfrom2to30ugofarsemc,add7ml(1+1)H2S04 and5 ml conc HN03 Evaporate the sample to S03 fumes CautIOn Ifthe sample chars, stop the dIgestIOn ImmedIately, cool and add addItIOnal conc HN03 Contmue dIgestIOn addmg addItIOnal conc HN03as necessary 22 If the sample remams colorless, or straw-yellow dunng evolutIOn of S03 fumes, the dIgestIOn IS complete 23 Cool the dIgested sample, add about 25 ml dIstIlled water, and agam evaporate to S03 fumes to expel OXIdes of mtrogen 24 The sample IS now ready for analysIs usmg eIther the hydnde or spectrophotometnc procedure 3 Interferences 3 1 All traces of mtnc aCId must be removed before eIther the spectrophotometnc or the hydnde procedures are apphed OXIdes of mtrogen should be expelled by takmg the sample to fumes of S03 4 Notes 4 1 The dIgestIOn step may be carned out m a flask on a hot-plate or m a KJeldahl apparatus ThIS dIgestIOn step may also be used, m effect, to concentrate the sample, masmuch as any SIze volume may be processed BIbliography 1 Standard Methods for the ExammatlOn ofWater and Wastewater, p285, method 404B, step 4a, 14th EdItIOn (1975) Approved for NPDES and SDWA Issued 1978 2065-1PDF Image | Methods for Chemical Analysis of Water and Wastes
PDF Search Title:
Methods for Chemical Analysis of Water and WastesOriginal File Name Searched:
epa600_4_79_020.pdfDIY PDF Search: Google It | Yahoo | Bing
CO2 Organic Rankine Cycle Experimenter Platform The supercritical CO2 phase change system is both a heat pump and organic rankine cycle which can be used for those purposes and as a supercritical extractor for advanced subcritical and supercritical extraction technology. Uses include producing nanoparticles, precious metal CO2 extraction, lithium battery recycling, and other applications... More Info
Heat Pumps CO2 ORC Heat Pump System Platform More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)