Calcium Pretreated Hevea brasiliensis Sawdust for Copper Removal: Batch and Column Study

Table 1

Quantitative description of the Langmuir, Freundlich, and Temkin models in adsorption of copper onto CaHBSW.

Isotherm; model	Mathematical equation and references	Notations	Plots	Results
Langmuir	[23]	: adsorption capacity at equilibrium (mg/g), : equilibrium concentration of the copper ion in solution (mg/L), : Langmuir constant (L/mg), and : maximum copper ion adsorption capacity per unit weight of adsorbent (mg/g)	Figure 10	(mg/g); (L/mg)	37.74; 0.91; 0.996
Freundlich	[24]	: Freundlich coefficients, : adsorption capacity at equilibrium (mg/g), : concentration of copper solution at equilibrium (mg/L), and n: heterogeneity factor	Figure 11	(mg/g)	16.19; 2.09; 0.927
Temkin	[25]	, : Temkin constant (J/mol), : absolute temperature in Kelvin (K), : gas constant (8.314 J/mol K), and : Temkin isotherm constant (L/g)	Figure 12	(J/mol); (L/g)	8.66; 290.94; 7.97; 0.984