Jan 28, 2015
"Preparation of bone char in ceramic kilns as used in the northern part of Thailand is normally a calcination rather than a charring process. This laboratory study shows that firing the cleaned bones up to 500°C and then gradually opening the kiln gate and letting it cool down results in bone char of a good quality and a with maximum fluoride removal efficiency of 91.8 %. "
http://www.de-fluoride.net/2ndproceedings/90-93.pdf