Removal of Cr(III) from Water Solutions and Wastewater Using Immobilized Sporopollenin by 1,8-dihydroxyanthracene-9,10-dione

Abstract

It is advantageous to use solid support adsorbents such as sporopollenin to remove heavy metals from aqueous solutions. In this paper, the
compound of 3-chloropropyl)trimethoxysilane was first modified on the surface of a sporopollen, which showed great resistance to excellent
mechanical properties and chemical and biological attack.Afterwards, 1,8-dihydroxyanthracene-9,10-dione (Danthron) compound was
immobilized on the surface of the modified sporopolenin (Sp-CPTS) and a new adsorbent material SP-CPTS-Danthron was obtained. Our
new adsorbent material (SP-CPTS-Danthron) was characterized by Fourier transform infrared spectroscopyandScanning Electron Microscopy.
Various factors such as pH, temperature and initial concentration, contact time were investigated for sorption of Cr(III) metal ions inaqueous
solution and wastewater to the surface of SP-CPTS-Danthron adsorbent. Freundlich, D-R (Dubinin-Radushkevich) and Langmuir adsorption
isotherms calculatedfrom the experimental results.Dubinin-Radushkevich isotherm with high R2 value revealed that Cr(III) adsorption in SpCPTS-Danthron adsorbent followed the mechanism of chemisorption. Experimental results of thermodynamic parameters such as enthalpy,
entropy and free energy were investigated and the data obtained were used to explain the sorption mechanism.The results showed that this
Sp-CPTS-Danthron adsorbent was successfully used to separate Cr(III)metal ions from aqueous solutions and wastewaters.