Adsorption of Chromium(VI) onto Freshwater Snail Shell-Derived Biosorbent from Aqueous Solutions: Equilibrium, Kinetics, and Thermodynamics

Table 2

The calculated kinetic parameters of Cr(VI) adsorption onto FSS of models at various temperatures.

	Unit	Temperature
		20°C	30°C	40°C
Pseudo-first-order model
qe	mg/g	6.65	6.22	5.24
k1	1/min	0.174	0.239	0.139
R^2	—	0.920	0.987	0.798
Pseudo-second-order model
qe	mg/g	6.78	6.34	5.56
k2	g/mg × min	0.063	0.068	0.034
R^2	—	0.995	0.997	0.931
Elovich model
α	mg/g × min	9.853	9.562	9.292
β	mg/g	2.422	1.779	1.348
R^2	—	0.895	0.977	0.963