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<p>In this work, three samples of nitrogen-doped TiO<sub>2 </sub>prepared at different calcination temperatures (400, 450 and 500 °C) were applied for the adsorption of Direct Black 38. Kinetic studies about the adsorption of Direct Black 38 on nitrogen-doped TiO<sub>2 </sub>were performed under different initial dye concentrations<br />
(75-175 mg l<sup>-1</sup>). Pseudo-first and pseudo-second order models were fitted with the experimental data. The results revealed that nitrogen-doped TiO<sub>2 </sub>synthesized at 400 °C presented the more adequate characteristics for adsorption purposes, such as specific surface area of 151 m<sup>2</sup> g<sup>-1</sup>. The adsorption kinetics agreed with the pseudo-second order model, at initial dye concentrations from 75 to 175 mg l<sup>-1</sup>. The maximum adsorption capacity predicted by the pseudo-second order model was 138.3 mg g<sup>-1</sup>, and was obtained using nitrogen-doped TiO<sub>2</sub> synthesized at 400 °C. In summary, these results revealed that nitrogen-doped TiO<sub>2</sub> is a good material for the removal Direct Black 38 from aqueous solutions by adsorption. </p>
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