Adsorption of basic yellow 87 from aqueous solution onto two different mesoporous adsorbents

The adsorption characteristics of basic yellow 87 from aqueous solution were investigated using two mesoporous materials: MCM41 and carbon aerogel (MCA). The adsorbents were analyzed by N2 adsorption–desorption technique and transmission electron microscopy to elucidate the effect of pore properties on the adsorption behavior of basic yellow 87. Three adsorption isotherms were used to model the equilibrium adsorption of basic yellow 87 on two mesoporous adsorbents. The result indicates that the Redlich–Peterson isotherm model describes the adsorption of basic yellow 87 extremely well. The adsorption process of MCM41 was exothermic and that of MCA was endothermic. Kinetic studies show that the adsorption of MCM41 and MCA followed the pseudo-second-order kinetic model. Batch experiments were conducted to study the effects of pH (1.2–13.0), dosage (0.025–0.200 g/50 mL), and particle size (5–10, 10–20, 20–40, and ≥200 mesh) on dye adsorption. The mesoporous adsorbents were highly effective as adsorbents for basic yellow 87 from aqueous solution. In particular, the initial adsorption rate of MCM41 was faster than that of MCA, but its adsorption capacity in dilute solutions was lower than that of MCA. The relatively low cost and high capabilities of MCM41 and MCA make them potentially attractive adsorbents for the removal of dyes from aqueous solution.

► Equilibrium adsorption isotherm data agree well with the Redlich–Peterson model for MCM41 and carbon aerogel (MCA). ► The adsorption process of MCM41 was exothermic and that of MCA was endothermic. ► Kinetic studies indicate that the adsorption of MCM41 and MCA followed the pseudo-second-order kinetic model. ► MCM41 yielded faster initial adsorption rate than did MCA, but lower adsorption capacity in dilute solutions compared with MCA. ► The adsorption of basic yellow 87 was dependent on solution pH, adsorbent dosage, and adsorbent particle size.