170135_inorganicventures_flipping

13.4 Sample Preparation by Fusion

Sodium or potassium hydroxide fusions: low temperature Flux - NaOH (mp 321 0 C) ; KOH (mp 404 0 C)

Crucible - Ag 0 ; Ni 0 (alkali hydroxides attack Pt 0 )

Flux:Sample ratio - 20:1

Temperature - 500 0 C ( max of 600 0 C /Ni 0 and 700 0 C /Ag 0 ). More crucible attack at higher temperatures.

Most Popular Applications - Silicates ( glass, porcelain, kaolin etc.)

13.5 Sample Preparation by Fusion

Oxida&ve potassium hydroxide fusions: low temperature

Flux - (7:1)KOH : KNO 3

Crucible - Ag 0 Flux:Sample raAo - 7:1

Temperature - 650 0 C ( max of 700 0 C /Ag 0 ). More crucible aIack at higher temperatures. Most Popular ApplicaAons - Ruthenium, chromite, “Organics” (“Organics” refers to organic containing samples. Both the sodium and potassium hydroxide/nitrate mixtures have been used for a wide variety of biological materials, soils, coal and organic samples.)