Synthesis and Characterization of Hydroxyapatite- (HAP-) Clay Composites and Adsorption Studies on Methylene Blue for Water Treatment

Table 2

Adsorption capacities for some related adsorbents.

Adsorbent	Adsorption capacity (mg/g)	Reference
Raw kaolin	8.8	[14]
Raw kaolin	7.59	[14]
NaOH treated pure kaolin	20.49	[14]
NaOH treated raw kaolin	16.34	[14]
Clay	6.3	[12]
Bentonite	151–175	[14]
HAP	14.3	[43]
HAP:Bentonite mix	20.70	This research