Non-acidic synthesis of phosphatized dolomite and its sorption behaviour towards Pb ²⁺, Zn²⁺, Cu²⁺, Cd²⁺, Ni²⁺, Sr²⁺ and Co²⁺ ions in multicomponent aqueous solution

The present work proposes the soft non-acidic method for preparing granular phosphate sorbents under standard conditions (25 °C, 101.3 kPa) using thermally activated dolomite as a cheap source of Ca and Mg, with NaH₂PO₄,Na₂HPO₄ and Na₃PO₄ aqueous solutions as phosphating reagents. The effect of the reagents’ properties and contact time on the phase and chemical compositions, adsorption and textural properties of the obtained sorbents was studied. The most effective sorbents were highly efficient. Up to 90%–95% of Pb²⁺,Zn²⁺,Cu²⁺,Cd²⁺,Ni²⁺,Sr²⁺ and Co²⁺ was removed from multicomponent aqueous solutions in dynamic mode (at initial concentrations of 5 mg L⁻¹, linear velocity 10 m h⁻¹). The influence of phase, chemical composition and surface properties of sorbents on their behaviour towards bivalent metal ions was also discussed.