Table 2.

Cr removal comparison using different materials.

No.	Materials	Optimum pH	Adsorption capacity (mg/g)	Contact time (min)	Reference
1	Chitosan–magnetic biochar (from loofah)	3	28	n.a	[8]
2	Spent tea leaves treated with ascorbic acid	2	93	n.a	[19]
3	Magnetic–activated carbon from rice husk	2	10	120	[15]
4	Commercial activated carbon from wood	2	242	n.a	[7]
5	CMAT	2	200	90	this study