Adsorptive Removal of Alizarin Red S onto Sulfuric Acid-Modified Avocado Seeds: Kinetics, Equilibrium, and Thermodynamic Studies

Table 5

Rate constants and other parameters for the adsorption kinetics.

Models	Parameters	Values
		50 mg/L	100 mg/L	150 mg/L	200 mg/L	250 mg/L
	qe, exp (mg/g)	17.15	32.92	47.53	60.86	68.95
PFO	k1 (min^-1)	0.1091	0.08358	0.0722	0.06646	0.06241
	qe, cal (mg/g)	16.88	33.85	49.55	64.08	73.7
	R^2	0.9845	0.9604	0.9434	0.9359	0.9275
	SSE	0.4078	7.334	28.97	61.52	100.4
	RMSE	0.3193	1.354	2.691	3.922	5.011
PSO	k2 (g/mg.Min)	0.00816	0.002414	0.001241	0.0008203	0.0006321
	qe, cal (mg/g)	19.15	40.46	61.26	80.82	94.48
	R^2	0.9063	0.8943	0.886	0.8843	0.8797
	SSE	2.465	19.59	58.32	111	166.6
	RMSE	0.785	2.213	3.818	5.269	6.454
Intraparticle diffusion	kp (mg/(g.min^(1/2))	1.127	3.0413	5.098	7.043	8.491
	C	9.0173	12.133	12.584	12.511	11.036
	R^2	0.6229	0.6512	0.668	0.683	0.69