Comparison of the pseudo first-order and pseudo second-order rate constants for Cr(vi) adsorption onto the RBC-TiO₂@C nanocomposite at different initial concentrations and temperatures.

Parameter		q e (exp) (mg g−1)	Pseudo first-order			Pseudo second-order
			q e (cal) (mg g−1)	k 1 (min−1)	r 1 2	q e (cal) (mg g−1)	k 2 (g mg−1 min−1)	r 2 2
Concentration (mg L−1)	25	31.21	30.46	0.0299	0.9782	31.15	0.1073	0.9999
	50	58.56	54.38	0.0355	0.9581	58.48	0.0311	0.9999
	75	66.69	61.72	0.0449	0.9327	66.67	0.0300	0.9998
	100	74.41	72.84	0.0292	0.9787	74.07	0.0380	0.9998
	125	74.24	71.15	0.0645	0.9449	74.08	0.1139	0.9999
	150	77.20	71.68	0.0311	0.8980	76.92	0.0445	0.9999
Temperature (K)	288	77.20	75.56	0.0525	0.9226	77.51	0.0925	0.9999
	293	74.41	72.84	0.0292	0.9787	74.07	0.0380	0.9999
	298	72.56	68.29	0.0472	0.9538	72.46	0.0373	0.9999
	303	70.76	70.05	0.0603	0.9677	70.92	0.0258	0.9999
	308	67.06	66.71	0.0592	0.9568	67.57	0.0181	0.9999