Mesoporous Carbon from Optimized Date Stone Hydrochar by Catalytic Hydrothermal Carbonization Using Response Surface Methodology: Application to Dyes Adsorption

Table 4

Parameter of the adsorption isotherms for MB and OM at 25°C.

Isothermal model	Parameters	BM	OM
Langmuir	Qm (mg g^−1)	657.89	384.62
	KL (L mg^−1)	0.098	0.329
	R^2	0.83	0.89
	RL range	0.012–0.29	0.0036–0.0108
Freundlich	K^F (mg/g (1/mg))	407.320	265.49606
	1/nF	0.0813	0.0587
	R^2	0.82	0.83