Nano silica particles loaded with CYANEX-921 for removal of iron(III) from phosphoric acid

Abstract

A simple route for preparation of organically modified spherical silica (SiO₂) nanoparticles with CYANEX 921 has been discussed. These modified particles has been used to remove Fe³⁺-SCN complex from 9M phosphoric acid. SEM, XRD, IR and EDS have been used to Characterized the powder in its several stages. The effect of SiO₂ weight, thiocyanate concentration, initial Fe (III) concentration, H₃PO₄ concentration, stirring time, temperature and loaded SiO₂ weight have been used to study the removal percent. The loaded silica succeeded in removal of 70% of Fe (III). Langmuir isotherm model well fit the experimental data with maximum sorption capacity 45.45 mg/g. The reaction kinetic is found to follow the pseudo second order kinetic model the adsorption reaction shows exothermic behavior.