Sorption kinetics models for MO uptake by An/CNT composite.

Kinetic model	Linear form	Parameters	Ref.
Pseudo-first order	ln(qe − qt) = ln qe − k1t	q t (mg g−1): removed amount of MO at time t	53
		q e (mg g−1): equilibrium sorption uptake
		K 1 (g mg−1 min−1): rate constant of the first-order adsorption
		k 1: −slope
		q e (cal): EXP(intercept)
Pseudo-second order		q t (mg g−1): removed amount of MO at time t	54
		q e (mg g−1): equilibrium sorption uptake
		K 2 (g mg−1 min−1): rate constant of the second-order adsorption
		q e (cal) = 1/slope
		k 2 = (slope) × 2/intercept
Intra-particle diffusion	q t = kpt1/2 + C	q t (mg g−1): removed amount of MO at time t	55
		K p (mg g−1 min−0.5): intra-particle diffusion rate constant
		C (mg g−1): intercept of the line which reflects the thickness of the boundary layer
		k p = slope
		C = intercept