Kheibar Dashtian - Research Laboratory of Spectrometry & Micro and Nano Extraction, Department of Chemistry, Iran University of Science and Technology, Tehran, Iran
Rohallah Zare-Dorabei - Research Laboratory of Spectrometry & Micro and Nano Extraction, Department of Chemistry, Iran University of Science and Technology, Tehran, Iran

In this work, design of a novel solid optical sensor for single-step detection and removal of Pb(II) ions based on dithizone (DZ) anchored on mesoporous SBA-15 with rapid colorimetric response and high selectivity for the first time was reported. Central composite design (CCD) was applied to evaluate the interactive effects of adsorption variablessuch as pH value, mesoporous SBA-15 dose, contact time and initial concentration, and also, the optimum experimental conditions were found with desirability function (DF) combined CCD.This solid optical sensor exhibits a linear range of 1.0 to 100 μg mL-1 of the Pb(II) ion concentration with a detection limit of 0.07 μg mL-1. This solid optical sensor was applied to the determination and removal of Pb(II) in spiked sample. Various isotherm models for fitting the experimental equilibrium data were studied and Langmuir model was chosen as an efficient model.And also, various kinetic models models for analysis of experimental adsorption data were studied and pseudo second order model was chosen as an efficient model.

Solid optical sensor; Pb(II) ions; Central Composite Design; Mesoporous SBA- 15; Desirability function