Adsorption of methylene blue on the composite sorbent based on bentonite-like clay and hydroxyapatite

The adsorption of methylene blue from model aqueous solutions on bentonite-like clay, hydroxyapatite, and a composite sorbent has been investigated. The kinetic and thermodynamic parameters of adsorption in the temperature range 298-333 К have been calculated. The process is found to obey Langmuir isotherm equation. It is spontaneous but slightly endothermi