Synthesis of the White Calcium Cyanamide from Shells, Egg Shells, and Chicken Bones

Masahiro Ogawa*, Kohei Yamauchi*, Hisao Sugihara**, Hiroyasu Nishiguchi*, Tatsumi Ishihara* and Yusaku Takita*
* Department of Applied Chemistry, Faculty of Engineering, Oita University
** Tsukumi Fine Ceramics Research Center
+ Correspondence should be addressed to Masahiro Ogawa:
Department of Applied Chemistry, Faculty of Engineering, Oita University
(700 Dannoharu, Oita, 870-1192 Japan)

Large amounts of wastes containing higher levels of calcium have been generated from the byproducts marine and livestock industries, i.e., shells, eggshells, and bones. Chemical and energy industries generate waste CO in a process of coke formation and waste NH3 in the hydrodenitrogenation of coals and petroleum. If CaCN2 can be formed from these wastes, the process could contribute to the reduction of solid wastes. With this point in mind, CaCN2 formation from shells, eggshells, and chicken bones was studied using pure NH3 and CO. About 18-20wt% CaCN2 was formed from both kinds of shells through reaction with NH3 and CO at 600C[Celsius degree] for 6-10 h and about 8wt% from chicken bones under the same conditions.
It was estimated from the balance of gaseous compounds that the major reaction is 6CaO+6NH3+6CO->4CaCO3+2CaCN2+9H2+N2.

Key words: calcium cyanamide synthesis, shell, egg shell, chicken bone