Kinetic Model for pH Variation Resulted from Interaction of Aqueous Solution Contaminated with Nickel Ions and Cement Kiln Dust

Table 3

Simulation of predominant mechanisms by different kinetic models.

Mechanism	Name of model	Parameter	Co (mg/L)
			200	400
Precipitation-sorption	First order	qc	17.03	26.19
		k1	0.215	0.141
		R^2	0.460	0.620
		SSE	13.99	8.92
	n^th order	qc	21.280	32.436
		kn	6.931 ∗ 10^−6	1.883 ∗ 10^−6
		N	5.397	4.967
		R^2	0.961	0.854
		SSE	0.271	2.067
Sorption	First order	qc	11.12	10.11
		k1	0.347	0.055
		R^2	0.370	0.854
		SSE	0.160	4.040
	n^th order	qc	12.520	15.67
		kn	202 ∗ 10^−6	6 ∗ 10^−6
		n	8.320	4.489
		R^2	0.973	0.974
		SSE	0.007	0.595
Precipitation	Avrami	qc	16.860	11.377
		k1	0.166	0.319
		a	1.606	0.197
		R^2	0.969	0.964
		SSE	0.092	0.132