Open AccessCadmium immobilization by hydroxyapatite
Author(s) -
Ivana Smičiklas
Publication year - 2003
Publication title -
hemijska industrija
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.147
H-Index - 19
eISSN - 2217-7426
pISSN - 0367-598X
DOI - 10.2298/hemind0303101s
Subject(s) - sorption , sorbent , cadmium , coprecipitation , adsorption , environmental remediation , chemistry , ion exchange , environmental chemistry , ionic strength , salt (chemistry) , contamination , precipitation , chemical engineering , inorganic chemistry , ion , organic chemistry , aqueous solution , ecology , engineering , biology , physics , meteorology
The contamination of air, soil and water by cadmium is a great environmental problem. If cadmium occurs in nature in ionic form, soluble in water, it easily enters into the food chain. Hydroxyapatite (HAP), Ca-o(POA)e(OH)2 is a sparingly soluble salt and an excellent matrix for the removal of heavy metals from solutions. Considerable research attention has been paid to the bond between Cc/2+ ions and synthetic hydroxyapatite of known composition. The sorption mechanism is complex. The dominant process is ion exchange, but surface adsorption, surface complexation and coprecipitation can also contribute to the overall mechanism. The sorption capacity depends on the characteristics of hydroxyapatite itself and on the experimental conditions. Under optimum conditions a maximum capacity of 0.8 mol Cd2+/mol HAP can be achieved. HAP is a potential sorbent for the remediation of contaminated water and soil, for industrial waste treatment, and it is also referenced as a material that can be used as a barrier around waste depositories