Simultaneous removals of cadmium(II) ions and reactive yellow 4 dye from aqueous solution by bone meal-derived apatite: kinetics, equilibrium and thermodynamic evaluations

Ofudje, Edwin A.; Adeogun, Idowu A.; Idowu, Mopelola A.; Kareem, Sarafadeen O.; Ndukwe, Nelly A.

doi:10.1186/s40543-020-0206-0

Journal of Analytical Science and Technology

Table 3 Kinetic parameters for the adsorption of Cd(II) ions and RY4 by BMDA

From: Simultaneous removals of cadmium(II) ions and reactive yellow 4 dye from aqueous solution by bone meal-derived apatite: kinetics, equilibrium and thermodynamic evaluations

		Cd(II) ion						RY4 dye
Pseudo-first order	C_o (mg/L)	40	80	120	160	200	240	40	80	120	160	200	240
	Q_{e exp} (mg g⁻¹)	22.40	47.10	70.10	90.40	112.60	133.40	21.500	33.600	56.100	65.600	72.600	87.400
	Q_{e cal} (mg g⁻¹)	22.31	46.63	69.97	89.38	110.95	131.27	21.439	32.924	55.763	64.256	70.858	84.916
	k_{1 × 10}² (min⁻¹)	0.055	0.037	0.052	0.060	0.060	0.062	0.036	0.039	0.036	0.041	0.045	0.046
	R²	0.998	0.997	0.999	0.999	0.997	0.997	0.999	0.997	0.999	0.999	0.997	0.997
	%SSE	0.086	0.470	0.126	1.022	1.651	2.134	0.061	0.676	0.337	1.344	1.742	2.484
	RMSE	0.010	0.052	0.014	0.114	0.183	0.237	0.007	0.075	0.037	0.149	0.194	0.276
	HYBRID	0.055	0.144	0.026	0.163	0.213	0.232	0.041	0.293	0.086	0.299	0.351	0.418
Pseudo-second order	Q_{e cal} (mg g⁻¹)	24.712	53.085	77.794	98.503	122.260	143.958	24.524	38.165	63.999	72.537	79.633	95.485
	k₂ × 10⁴ (g mg⁻¹ min⁻¹)	28.9	8.55	8.57	8.03	6.41	5.80	17.5	11.5	6.51	6.99	7.09	6.03
	R²	0.992	0.994	0.992	0.994	0.996	0.996	0.998	0.998	0.999	0.998	0.998	0.998
	%SSE	2.312	5.985	7.694	8.103	9.660	10.558	3.024	4.565	7.899	6.937	7.033	8.085
	RMSE	0.257	0.665	0.855	0.900	1.073	1.173	0.336	0.507	0.878	0.771	0.781	0.898
	HYBRID	1.336	1.611	1.413	1.175	1.129	1.048	1.762	1.709	1.763	1.366	1.262	1.210
Elovich	Q_{e cal} (mg g⁻¹)	21.59	43.45	67.75	87.40	107.64	127.63	20.033	30.918	51.958	60.684	67.390	81.052
	α (mg (g min)⁻¹)	5.16	6.11	11.64	22.73	32.57	44.43	2.314	4.297	5.933	9.036	12.346	15.023
	β (g mg⁻¹)	0.230	0.098	0.067	0.058	0.049	0.042	0.201	0.138	0.077	0.072	0.069	0.057
	R²	0.992	0.996	0.991	0.992	0.993	0.994	0.995	0.996	0.995	0.996	0.996	0.996
	%SSE	0.813	3.648	2.348	2.996	4.964	5.768	1.467	2.682	4.142	4.916	5.210	6.348
	RMSE	0.090	0.405	0.261	0.333	0.552	0.641	0.163	0.298	0.460	0.546	0.579	0.705
	HYBRID	0.538	1.199	0.495	0.490	0.659	0.646	1.046	1.239	1.139	1.157	1.105	1.119
Intraparticle diffusion	K_1d (mg g⁻¹ min^-0.5)	3.23	5.37	10.05	13.47	16.40	19.15	2.53	3.72	6.57	7.54	8.43	10.38
	C₁ (mg g⁻¹)	− 0.34	− 0.31	− 1.81	− 1.18	− 0.63	1.50	− 0.72	0.11	− 1.98	0.15	1.49	1.39
	R²	0.996	0.997	0.997	0.996	0.998	0.998	0.991	0.992	0.994	0.995	0.998	0.996
	K_2d (mg g⁻¹ min^-0.5)	0.49	1.75	1.45	1.73	2.26	2.66	0.75	1.30	1.90	2.35	2.41	2.87
	C₂ (mg g⁻¹)	15.96	23.38	50.73	67.08	81.95	97.54	11.37	15.78	30.05	33.35	39.55	47.76
	R²	0.997	0.994	0.997	0.998	0.998	0.998	0.994	0.992	0.995	0.993	0.994	0.995

Back to article page