Table 2. Summary of ion concentrations of EC12, DV12 and kaolinite clays before and after ion exchange.

Ion	EC12			DV12			Kaolinite
	Before [μg g− 1]	After [μg g− 1]	Fold change	Before [μg g− 1]	After [μg g− 1]	Fold change	Before [μg g− 1]	After [μg g− 1]	Fold change
Fe	10895	11797	1.1	14587	79.3.0	–	506.0	12061	23.8
Co	10.09	19.92	2.0	10.11	3.48	–	0.2	16.25	81.3
Cu	20.62	138.69	6.7	17.09	158.39	3.5	74.14	128.75	1.7
Zn	54.87	11.34	–	45.42	34.62	–	5.31	109.0	20.5