Effect of Physical and Chemical Activation on the Removal of Hexavalent Chromium Ions Using Palm Tree Branches

Table 2

Equilibrium isotherm constants of Cr(VI) adsorption onto raw and different activated adsorbents.

Model		Adsorbents
		RPB	APBH 20	APBH 50	APBS	APBK
Langmuir	𝑄𝑜	25	37	59	20	50
	𝐾𝐿	0.023	0.037	0.037	0.031	0.023
	𝑅^2	0.99	0.99	0.98	0.99	0.98
Freundlich	𝐾𝐹	0.23	2.3	4.5	2.7	6.02
	𝑛	1.03	1.05	1.1	1.75	1.14
	𝑅^2	0.91	0.93	0.92	0.93	0.92
Flory-Huggins	𝐾FH	0.02	0.017	0.027	0.019	0.045
	𝛼	3.4	0.79	1.5	1.2	1.68
	𝑅^2	0.91	0.90	0.90	0.92	0.92
	Δ𝐺^𝑜	−32.2	−31.1	−32.7	−33.0	−34.8