Sorption behavior of phosphate by fly ash discharged from biomass thermal power plant

Applied Biological Chemistry

Table 3 The parameter estimates and coefficients of determination (R²) for fit of the kinetic equation to experimental data of phosphate adsorption by BTP-FA at different initial phosphate concentration

Models	Parameters	250 mg/L	500 mg/L	1000 mg/L
Pseudo-first-order	q_e (mg/g)	8.97	13.70	25.9
	k₁ (1/h)	0.269	0.202	0.250
	R²	0.832	0.676	0.933
Pseudo-second-order	q_e (mg/g)	30.12	50.25	64.10
	k₂ (g/mg∙h)	0.041	0.030	0.030
	R²	0.995	0.998	0.999
Intraparticle diffusion	k_i1	23.49	38.76	40.50
	R²	0.964	0.990	0.947
	k_i2	0.46	0.62	2.07
	R²	0.846	0.921	0.943