Wet ashing methods

Look up a procedure that uses only a wet ash method. Which do you think is better Why ... 

Solid materials require decomposition to yield a solution before Al determination. Solids can often be solubilized by dry ashing at 600 C in a muffle furnace, followed by dissolution of the ash (Cedergren and Freeh 1987). Wet ashing methods. 

There are no universally accepted wet analytical methods for the characteri2ation of quaternary ammonium compounds. The American Oil Chemists Society (AOCS) has estabhshed, however, a number of appHcable tests (180). These include sampling, color, moisture, amine value, ash, iodine value, average molecular weight, pH, and flash point. 

Using the slurry-method and GF-AAS in Cu, Cr, Fe and Pb were determined in various pine needle samples, using NIST SRM 1575 Pine needles slurry as calibrant. Comparison of the obtained results showed good agreement with wet ashing (Carrion et al. 1988). 

Blood Wet ashing with acid mixtures residue dissolution in dilute HCI04 ASV with mercury-graphite electrode (NIOSH method P CAM 195) 40 pg/L 95-105 NIOSH 1977d... 

Blood Wet ashing with HN03 residue dissolution in dilute HN03 GFAAS (NIOSH method P CAM 214) 100 pg/L No data NIOSH 1977g... 

Blood and urine Wet ashing of sample with HN03, complexation with diphenylthio-carbazone, and extraction with chloroform Spectrophotometry (NIOSH method P CAM 102) 30 pg/L (blood) 12 pg/L (urine) 97 97 NIOSH 1977a... 

Air (particulate lead) Collection of particulate matter onto membrane filter wet ashing with HN03/ HCI04/ H2S04 dissolution in acetate buffer ASV with mercury-graphite electrode (Method P CAM 191) 0.16 pg/m3 90-110 NIOSH 1977c... 

Water (particulate and dissolved lead) Filtration of water through a 0.45 pm membrane filter (dissolved lead) particulate material dissolved by wet ashing (insoluble ICP/AES (EPA Method 200.7) 42 pg/L 94-125 EPA 1983a... 

A wet-ashing technique used for dissolution of graphite in perchloric acid involved boiling a mixture of 70% perchloric acid and 1% of chromium trioxide as an aqueous solution. This method was later applied to 6-14 mesh charcoal, and after boiling for 30 min the reaction rate increased (foaming) and accelerated to explosion. The charcoal contained traces of extractable tar. 

HS-I diet and fecal samples were dry ashed and HS-II and -III samples were prepared by a combination dry-wet ashing procedure (Hill et al. unpublished). The approved method of American Association of Cereal Chemists (7) was used for determining neutral detergent fiber. 

Bretthauer etal. [34] and Anderson etal. [35] described a method in which samples were ignited in a high-pressure oxygen-filled bomb. After ignition, the mercury was absorbed in a nitric acid solution. Pillay et al. [36] used a wet-ashing procedure with sulphuric acid and perchloric acid to digest... 

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