PDF Publication Title:
Text from PDF Page: 358
NOTE 3. Reagents 7 7, 78, 79, and 7 10 are IdentlCal to reagents 6 8, 62,63, and 66 descnbed under NItrogen, Ammoma (Colonmetnc, Tltnmetnc, PotentIOmetnc- DIstIllatIOn Procedure, Method 350 2) 8 Procedure 8 1 8 2 The dlst1l1atIOn apparatus should be pre-steamed before use by dlstlllIng a l l mIxture of dlst1l1ed water and sodmm hydroxlde-sodmm thIOsulfate solutIOn (74) untll the dlst1l1ate IS ammoma-free ThIS operatIOn should be repeated each time the apparatus IS out of serVIce long enough to accumulate ammoma (usually 4 hours or more) Macro KJeldahl system 8 2 1 Place a measured sample or the resIdue from the dIstIllatIOn m the ammoma 8 2 2 8 2 3 824 8 2 5 Dllute the sample, If reqUlred, to 500 ml WIth dlst1l1ed water, and add 100 ml sulfunc aCld-mercunc sulfate-potassmm sulfate solutlOn (7 3) Evaporate the mIxture m the KJeldahl apparatus untll S03 fumes are gIven off and the solutlOn turns colorless or pale yellow Contmue heatmg for 30 addltlOnal mmutes Cool the reSIdue and add 300 ml dlst1l1ed water Make the dlgestate alkalme by careful addltlOn of 100 ml of sodmm hydroxIde - thlOsulfate solutIOn (7 4) WIthout mlxmg NOTE 5' Slow addltlOn of the heavy caustIc solutlOn down the tllted neck of the dlgestlOn flask WIll cause heaVIer solutlOn to underlay the aqueous sulfunc aCId solutlOn WIthout loss of free-ammoma Do not mIX untll the dlgestlOn flask has been connected to the dlst1l1atlOn apparatus Connect the KJeldahl flask to the condenser WIth the tip of condenser or an extenslOn of the condenser tIp below the level of the bonc aCId solutlOn (7 6) m the recelvmg flask DISt1l1 300 ml at the rate of 6-10 mllmm, mto 50 ml of 2% bonc aCId (76) contamed m a 500 ml Erlenmeyer flask DIlute the dlst1l1ate to 500 ml m the flask These flasks should be marked at the 350 and the 500 ml volumes WIth such markmg, It IS not necessary to transfer the dlst1l1ate to volumetnc flasks For concentratlOns above I mg/I, the ammoma can be determmed tItnmetncally For concentratlOns below thIS value, It IS determmed colonmetncally The potentlOmetnc method IS applIcable to the range 005 to 1400 mg/I determmatlOn (for Orgamc KJeldahl only) mto an 800 ml KJeldahl flask The sample SIze can be determmed from the followmg table KJeldahl NItrogen m Sample, mg/l 0-5 5-10 10-20 20-50 50-500 Sample SIze ml 500 250 100 5 0 0 2 5 0 351 3-3PDF 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 | RSS | AMP |