Removal of Phosphate from Aqueous Solutions Using Chemically Synthesized Vaterite Polymorph of Porous Calcium Carbonate Nanoparticles under Optimized Conditions

Table 2

The kinetic parameters obtained using pseudo-first-order and pseudo-second-order rate laws at room temperature for the adsorption of phosphate on VPPCC nanoparticles.

Kinetic model	^ab	Rate constant	Value of rate constant^b	Units of rate constant
Pseudo-first-order	0.81		0.080	min^-1
Pseudo-second-order	0.98		0.083	g g^-1 min^-1

^a: regression coefficient. Note: g^-1 refers to the adsorbate and g refers to the adsorbent. ^bThe and values and the nonlinear regression correlations for pseudo-first-order and pseudo-second-order were measured by nonlinear regression analysis using Origin Pro 8.0.