Preparation, Characterization, and Application of Metakaolin-Based Geopolymer for Removal of Methylene Blue from Aqueous Solution

Table 5

Kinetic parameters for the adsorption of MB on geopolymer.

Dye C0 (mg/L)	Pseudo-first-order				Pseudo-second-order			Intraparticle diffusion model
	qexp	qe (mg/g)	k1 (1/min)		qe (mg/g)	k2 (g/mg min)		I (mg/g)	kid (mg/g min^0.5)
20	19.99	8.43	0.045	0.875	20.41	0.031	0.999	6.042	1.198	0.683
30	29.93	7.21	0.046	0.866	30.30	0.028	0.999	9.309	1.778	0.669
40	39.2	18.17	0.029	0.936	40	0.0098	0.999	11.64	2.334	0.692