Table 2.

Comparison of Cu(II), Pb(II), and Cd(II) adsorption capacities of this study with other recent reports using magnetic GO.

Sorbents	Environmental conditions	Metals	Q max⁡ (mg/g)	References
GO/Fe3O4	pH = 5.3, T = 20°C	Cu(II)	18.3	Li et al. [3]
GO/silica/Fe3O4	pH = 7.1, T = 25°C	Pb(II)	333.3	Wang et al. [9]
		Cd(II)	166.7
GO/Fe3O4/sulfanilic acid	pH =6.0, T = 25°C	Cd(II)	55.4	Hu et al. [7]
GO-MnFe2O4	pH =5.0, T = 25°C	Pb(II)	673	Kumar et al. [11]
Reduced GO/CoFe2O4	pH = 5.3, T = 25°C	Pb(II)	299.4	Zhang et al. [12]
	pH = 5.3, T = 35°C		274.7
	pH = 5.3, T = 45°C		253.2
GO/Mn-doped Fe(III) oxide	pH = 5.0, T = 25°C	Cd(II)	87.2	Nandi et al. [8]
		Cu(II)	129.7
GO/Fe3O4/sulfanilic acid	pH = 5.0, T = 20°C	Cu(II)	50.7	Hu et al. [6]
	pH = 5.0, T = 30°C		56.9
GO/Fe3O4	pH = 6.0, T = 20°C	Cu(II)	23.1	This study
		Pb(II)	38.5
		Cd(II)	4.4