Table 5.

Single metal removal using biochar: best fit of sorption isotherm model parameters

Biochar type [temperature (°C)]	Metal	Model	Parameter 1	Parameter 2	R ²	pH	Reference
Pig Manure (400)	Cd²⁺	Langmuir	q_max (mg g⁻¹) = 107	K_L (1 mg⁻¹) = 0.002	0.969	6	Kotodynska et al. (2012)
	Cd²⁺	Freundlich	K_F (mg g⁻¹) = 2.07	n = 3.82	0.970	6
	Pb²⁺	Langmuir	q_max (mg g⁻¹) = 175	K_L (1 mg⁻¹) = 0.011	0.996	6
	Pb²⁺	Freundlich	K_F (mg g⁻¹) = 5.99	n = 4.95	0.920	6
	Zn²⁺	Langmuir	q_max (mg g⁻¹) = 62.3	K_L (1 mg⁻¹) = 0.005	0.985	5
	Zn²⁺	Freundlich	K_F (mg g⁻¹) = 2.89	n = 2.10	0.985	5
Diary Manure (400)	Cd²⁺	Langmuir		K_L (1 mg⁻¹) = 0.001	0.990	6
	Cd²⁺	Freundlich		n = 3.06	0.830	6
	Pb²⁺	Langmuir		K_L (1 mg⁻¹) = 0.002	0.990	6
	Pb²⁺	Freundlich		n = 4.04	0.858	6
	Zn²⁺	Langmuir		K_L (1 mg⁻¹) = 0.006	0.970	5
	Zn²⁺	Freundlich		n = 2.70	0.928	5
Peanut Hull (400)	Pb²⁺	Langmuir	q_max (mg g⁻¹) = 49.9	K_L (1 mg⁻¹) = 0.59	0.912	5	Wang et al. (2015)
Peanut Hull (400)	Pb²⁺	Freundlich	K_F (mg g⁻¹) = 25.1	1 = 0.119	0.968	5
Medicine Residue (400)	Pb²⁺	Langmuir	q_max (mg g⁻¹) = 82.5	K_L (1 mg⁻¹) = 0.58	0.932	5
Medicine Residue (400)	Pb²⁺	Freundlich	K_F (mg g⁻¹) = 40.5	n = 0.121	0.976	5
Canna indica (600)	Cd²⁺	Langmuir	q_max (mg g⁻¹) = 140	K_L (1 mg⁻¹) = 1.03	0.876	5	Cui et al. (2016)
Canna indica (600)	Cd²⁺	Freundlich	K_F (mg g⁻¹) = 52.8	n = 0.26	0.740	5	Cui et al. (2016)
Pinewood (300)	Pb²⁺	Langmuir	q_max (mg g⁻¹) = 3.89	K_L (1 mg⁻¹) = 0.36	0.98	5	Liu and Zhang (2009)
Pinewood (300)	Pb²⁺	Frenudlich	K_F (mg g⁻¹) = 1.75	n = 4.77	0.47	5	Liu and Zhang (2009)
Rice husk (300)	Pb²⁺	Langmuir	q_max (mg g⁻¹) = 1.84	K_L (1 mg⁻¹) = 0.21	0.92	5
Rice husk (300)	Pb²⁺	Freundlich	K_F (mg g⁻¹) = 0.35	n = 2.07	0.95	5
Corn straw (300)	Zn²⁺	Langmuir	q_max (mg g⁻¹) = 11.0	K_L (1 mg⁻¹) = 0.232	0.998	5	Chen et al. (2011)
Corn straw (300)	Zn²⁺	Freundlich	K_F (mg g⁻¹) = 2.84	n = 3.336	0.898	5
Hardwood (450)	Zn²⁺	Langmuir	q_max (mg g⁻¹) = 4.54	K_L (1 mg⁻¹) = 0.061	0.998	5
Hardwood (450)	Zn²⁺	Freundlich	K_F (mg g⁻¹) = 0.72	n = 2.827	0.941	5
Pine Bark (400/450)	Cd²⁺	Langmuir	q_max (mg g⁻¹) = 0.34	K_L (1 mg⁻¹) = 0.0002	0.743	5	Mohan et al. (2007)
	Cd²⁺	Freundlich	K_F (mg g⁻¹) = 0.40	n = 0.35	0.778
	Pb²⁺	Langmuir	q_max (mg g⁻¹) = 3.0	K_L (1 mg⁻¹) = 0.226	0.963
	Pb²⁺	Freundlich	K_F (mg g⁻¹) = 1.28	n = 0.15	0.961
Oak Wood (400/450)	Cd²⁺	Langmuir	q_max (mg g⁻¹) = 0.37	K_L (1 mg⁻¹) = 0.037	0.575	5
	Cd²⁺	Freundlich	K_F (mg g⁻¹) = 0.23	n = 0.12	0.584
	Pb²⁺	Langmuir	q_max (mg g⁻¹) = 2.62	K_L (1 mg⁻¹) = 0.163	0.908
	Pb²⁺	Freundlich	K_F (mg g⁻¹) = 0.77	n = 0.22	0.948