Biosorptive Removal of Cadmium(II) and Copper(II) Using Microwave-Assisted Thiourea-Modified Sorghum bicolor Agrowaste

Table 3

Equilibrium parameters for Cu(II) and Cd(II) biosorption.

Langmuir isotherm parameters
Adsorbents	Metal	RMSE	b (L/mg)	qm (mg/g)	SL (m^2/g)	RL
SB	Cu(II)	0.028	0.111	4.149	2.19	0.311–0.083
	Cd(II)	0.038	0.028	8	2.38	0.645–0.267
TSB	Cu(II)	0.162	0.095	15.151	7.98	0.344–0.046
	Cd(II)	0.279	0.063	17.241	5.13	0.443–0.067
Freundlich isotherm parameters
Adsorbents	Metal	RMSE		KF		n
SB	Cu(II)	0.071		0.6531		2.0661
	Cd(II)	0.034		0.2805		1.2919
TSB	Cu(II)	0.517		2.4717		2.4752
	Cd(II)	0.634		1.1967		1.8149
Temkin isotherm parameters
Adsorbents	Metal	RMSE		BT (kJ/mol)		KT (L/g)
SB	Cu(II)	0.034		1.058		0.7733
	Cd(II)	0.054		1.460		0.3604
TSB	Cu(II)	0.261		2.860		1.3551
	Cd(II)	0.422		3.711		0.3758
Dubinin–Radushkevich isotherm parameter
Adsorbents	Metal	RMSE		E (kJ/mol)		qm (mg/g)
SB	Cu(II)	0.138		0.469		2.932
	Cd(II)	0.153		0.328		2.795
TSB	Cu(II)	0.599		0.572		10.859
	Cd(II)	0.754		0.304		10.155