Optimizing the Extraction Conditions of Hydroxytyrosol from Olive Leaves Using a Modified Spherical Activated Carbon: A New Experimental Design

Table 5

Adsorption isotherms and kinetic models of HT adsorption.

Models	Equations	Constants
Langmuir		(L.g^−1)	(mg.g^−1)
		109.00	91.743	0.998
Freundlich		(mg.g^-1)
		148.41	4	0.996
Pseudo-first-order		(mg.g^-1)
		28.18	0.0021	0.96
Pseudo-second-order		(mg.g^-1)
		46.3	0.0005	0.9977
Intraparticle diffusion		(mg g^-1 min^-0.5)
		2.701		0.98

: the maximum adsorption capacity (mg g⁻¹); : the quantity of polyphenols at saturation of monolayer capacity (mg g⁻¹); : the Langmuir constant; : the Freundlich constant; : the Freundlich exponent. : the pseudo-first-order rate constant for adsorption (min⁻¹); : the pseudo-second-order rate constant for adsorption (mg. g⁻¹ min⁻¹); Kid: the rate constant for intraparticle diffusion (mg. g⁻¹ min^−0.5).