Table 2.

Adsorption kinetics parameters for As(V) and As(III) adsorption on iron hydroxide nanopetalines at pH 4.0 and 8.0.

Models	As(V)		As(III)
	pH 4.0	pH 8.0	pH 4.0	pH 8.0
Pseudo-first-order model
k1 (h−1)	20.43	7.36	4.71	6.10
qe (mg/g)	135.51	114.91	61.25	95.67
R2	0.769	0.842	0.876	0.843
ARE (%)	15.65	3.78	3.63	3.35
Pseudo-second-order model
k2 (g/(mg h))	0.0259	0.0136	0.0058	0.0126
qe (mg/g)	146.41	116.69	70.32	108.81
R2	0.984	0.961	0.973	0.961
ARE (%)	1.65	1.13	1.87	1.31
Elovich model
α (mg/g/h)	6.14 × 109	7.18 × 1041	1.74 × 104	6.01 × 104
β (g/mg/h)	0.167	0.855	0.166	0.114
R2	0.965	0.607	0.958	0.957
ARE (%)	0.201	1.02	0.938	1.73