The effect of pH and ionic strength on the adsorption of glyphosate onto ferrihydrite

Table 3 Surface area, maximum adsorption capacity and maximum adsorption densities values for iron oxides

Mineral	SA (m² g⁻¹)	MAC (mg g⁻¹)	MAD (µmol m⁻²)	Adsorption conditions	References
Ferrihydrite 6 line	234	54.88^a	1.39^a	NaCl 0.10 mol L⁻¹, pH 5.0	This work
Ferrihydrite 6 line	234	32.83^a	0.83^a	NaCl 0.01 mol L⁻¹, pH 5.0	This work
Ferrihydrite 2 line	343	107^a	1.85^a	KCl 0.10 mol L⁻¹, pH 7.0	[16]
Hematite	33	14.5^a	2.61^a	KCl 0.10 mol L⁻¹, pH 7.0	[16]
Hematite	11.1	6.31^b	3.36^b	pH 4.5	[13]
Hematite	11.1	7.89^b	4.21^b	pH 7.0	[13]
Goethite	50.7	16.3^b	1.90^b	pH 4.5	[13]
Goethite	50.7	21.6^b	2.52^b	pH 7.0	[13]
Goethite	40	10.1^c	1.50^c	KCl 0.010 mol L⁻¹, pH 7.0	[15]
Goethite	40	11.8^c	1.75^c	KCl 0.10 mol L⁻¹, pH 7.0	[15]
Goethite	40	11.8^c	1.75^c	Ca(Cl)₂ 0.01 mol L⁻¹, pH 7.0	[15]
Goethite	60	21.3^a	2.10^a	NaCl 0.01 mol L⁻¹, pH 5.0	[19]
Goethite	60	17.2^a	1.70^a	NaCl 0.01 mol L⁻¹, pH 7.2	[19]

SA surface area, MAC maximum adsorption capacity, MAD maximum adsorption densities
^aLangmuir isotherm, ^bFreundlich isotherm, ^c initial concentration 2.5 mL of 80 mmol L⁻¹ of glyphosate

ISSN: 1467-4866