استخلاص و تقييم لمركبات السيلكون من تربة محلية‘ استخلاص ايون الحديد الثلاثي من محاليله المائية وتطبيقاته المختلفة

Extraction and Evaluation of Silicon Compounds from Local Soil, Extraction of Iron (III) Ions from Aqueous Solution and Their Analytical Application

Abstract
Silica was successfully extracted from selected local soil samples from different areas of Karbala city using Sol-Gel method. The extraction method was simple and environmentally friendly. Organosilica (1-nitroso-2-naphthal silica) was then synthesized by reacting the extracted silica from the sand sample with an organic chelating reagent (1-nitroso-2-naphthal). The silica and organosilica compounds were then characterized using different techniques such as EDX, SEM, BET, AFM, XRD, FTIR, and TEM. EDX measurement revealed that the sandy soil contains a high percentage of silica. SEM technique was used to study the morphology of silica and organosilica. XRD technique showed that the silica and organosilica had broad peaks indicating their non-crystalline nature, while the presence of some sharp peaks in the organosilica indicated the presence of the organic reagent. FTIR analysis revealed the functional groups in silica, organosilica, siloxane, and silanol in silica. The surface area and pore volume of silica and organosilica using BET confirmed that both are characterized by mesoporous structures. Furthermore, transmission electron microscopy (TEM) and atomic force microscopy (AFM) images provided insights into the internal structure and surface roughness of silica and organosilica. Silica and organosilica were successfully used as the solid phase for the dispersed solid-phase extraction method and were successfully applied to extract iron complexes from aqueous solutions. The physicochemical conditions of the extraction were studied. Iron complexes were separated using silica and organosilica under the optimum conditions (neutral medium, reagent concentration 0.04 mol/L, temperature 35 and 40°C respectively, and stirring time 15 min). The iron complex extraction rate at 99.5% of silica was higher than used 87% with organosilica due to the surface properties of silica and organosilica. The method was also successfully applied to pharmaceutical samples containing iron ions, and the value of this confirms that it is an accurate, selective, sensitive, easy and fast method.