Nitrogen-Doped Carbonaceous Materials for Removal of Phenol from Aqueous Solutions

Table 3

Pseudo-first-order and pseudo-second-order constants for the adsorption of phenol on BK at 25°C.

𝐶𝑜 (mg/L)	Pseudo-first-order kinetic model				Pseudo-second-order kinetic model
	𝑄𝑒 cal (mg/g)	𝑘1 (1/h)	𝑅^2	Δ𝑄 (%)	𝑄𝑒 cal (mg/g)	𝑘2 (1/h)	𝑅^2	Δ𝑄 (%)
100	4.69	0.006	0.863	47.20	40.00	0.65	0.992	16.17
200	6.25	0.012	0.824	49.30	43.47	0.71	0.998	18.58
300	10.29	0.013	0.983	56.21	53.48	0.98	0.988	21.01
500	40.42	0.003	0.932	37.45	39.37	1.12	0.991	19.55

𝐶_𝑜: starting concentration; 𝑄_𝑒 cal: amount of adsorbate adsorbed at equilibrium; Δ𝑄: applicability; 𝑅: correlation coefficient; 𝑘₁: rate constant of pseudo-first-order sorption; 𝑘₂: rate constant of pseudo-second-order sorption.