Livingston Posted February 24, 2015 Posted February 24, 2015 I was curious to find out if Replacing sodium Oxalate with sodium bicarb? I was told that I could? Any thoughts or facts or experience? Any help much greatly appreciate it.
Arthur Posted February 24, 2015 Posted February 24, 2015 The Oxalate is the (only? ) insoluble salt of sodium. It's used because it's not susceptible to dampness. The bicarbonate may attract moisture and may slow the reaction -CO2 gas evolved. BUT the only real test is a small batch produced and fired. Obviously LOTS depends on what the compound is and what function the bicarb is meant to do.
WSM Posted February 24, 2015 Posted February 24, 2015 I was curious to find out if Replacing sodium Oxalate with sodium bicarb? I was told that I could? Any thoughts or facts or experience? In some glitter formulations sodium bicarbonate works to give a gold color. There are few insoluble sodium compounds and where concerns about hydroscopicity of the composition exist, sodium oxalate has been the standard for the longest time. WSM
schroedinger Posted February 24, 2015 Posted February 24, 2015 It works, but you won't get the same effect.Both bicarb and oxalate are used to give spritzles a slight delay and glitter effect.
Livingston Posted February 25, 2015 Author Posted February 25, 2015 Thanks guys!!! The formula is for a yellow and it's says you can use cryolite or sodium oxalate. I'm not sure if this info helps with my question.
Mumbles Posted February 25, 2015 Posted February 25, 2015 Sodium oxalate is water soluble. Not extremely soluble, but soluble none the less. Cryolite on the other hand is insoluble. Since it's just a colorant (probably), I bet bicarbonate will work just fine.
gregh Posted February 25, 2015 Posted February 25, 2015 I am sure I have read somewhere why NaCl isn't ever used for a yellow colorant, but could someone refresh my memory?
braddsn Posted February 25, 2015 Posted February 25, 2015 Greg that is ringing a bell. From my understanding, Sodium Oxalate and Cryolite can sometimes be interchanged, but I have not heard of Sodium Bicarb being used as a colorant.
Mumbles Posted February 25, 2015 Posted February 25, 2015 Sodium chloride tends to be corrosive to some metals. NaCl containing compositions tend to be rather hygroscopic as well.
WSM Posted February 26, 2015 Posted February 26, 2015 (edited) Sodium oxalate is water soluble. Not extremely soluble, but soluble none the less. Cryolite on the other hand is insoluble. Since it's just a colorant (probably), I bet bicarbonate will work just fine. Typically, sodium oxalate is used for yellow (or "gold") compositions, The sodium spectra is actually more of an amber hue, not unlike school bus yellow. Cryolite is a sodium containing mineral (a type of feldspar if memory serves) and insoluble in water. Cryolite is often used in very hot compositions containing magnesium or MgAl so they'll get hot enough to drive the yellow color. It's a bit of a trick to get them hot enough without over-doing it where the yellow gets washed out (pale from being too hot; look up black body radiation). WSM Edited February 27, 2015 by WSM
Recommended Posts