Experimental design for removal of lead ions from water samples using an engineered novel chitosan functionalized Schiff-base adsorbent

As an issue of public health, lead pollution has been a major concern for industrialists, environmentalists, and health workers. Researchers are always looking for the best way combat to Pb(II) contamination problem from the wastewater generated by industries. Here a new Schiff base ligand 2-(Piperazin-1-yl)ethan-1-imine methyl benzaldehyde (PEIMB), was constructed and used for the functionalization of chitosan. The magnetized chitosan (MCS-PEIMB) was characterized by FTIR, XRD, SEM, EDX, VSM, and TG techniques. The adsorption process of Pb(II) ions using the prepared adsorbent was investigated by the study of different factors such as pH values, adsorption time, the initial concentration of Pb(II) ions, and adsorbent dosage. The obtained results from Langmuir isotherm proved the monolayer adsorption of Pb(II) ions on the surface of MCS-PEIMB with the maximum adsorption capacity of 142.86 mg/g. The effect of some variables including pH values, adsorption time, and adsorbent dosage was assessed using a central composite design, and 4.02, 31.14 (Min), and 0.1044 (g/L) were obtained as optimum conditions, respectively. In addition, the adsorption mechanism of lead ions on the surface of MCS-PEIMB was studied using Gaussian 09 program package.