Efficient adsorption of Azure B onto CNTs/Zn:ZnO@Ni2P-NCs from aqueous solution in the presence of ultrasound wave based on multivariate optimization

Abstract This work devoted to the investigation of adsorption Azure B (Az-B) onto CNTs/Zn:ZnO@Ni 2 P-NCs, while dependency of process efficiency to variables was optimized by the application response surface methodology. This adsorbent successfully using small amount 0.031 g is applicable to the adsorption of the high amount of Az-B in a short time. The optimum variables for achievement of maximum Az-B adsorption percentage (98.84%) were achieved using 0.031 g of CNTs/Zn:ZnO@Ni 2 P-NCs, 26.1 mg L −1 initial Az-B concentration, 8.2 min sonication time and pH 6.3. The kinetic of Az-B adsorption followed pseudo-second-order kinetic and equilibrium data strongly follow the Langmuir model.