Solubility and Surface Complexation Studies of Apatites

Apatites undoubtedly are a diverse family of phosphate minerals which are crucial in a good number of natural and industrial processes. These are, for instance, applied as raw material in fertiliser manufacturing as well as in the removal of metal-contaminated soils. Hydroxyapatite Ca5(PO4)3OH, (HAP) and fluorapatite Ca5(PO4)3F, (FAP) are identical to the biological apatite which is the primary constituent of mammalian bone and teeth, plus they’re thus promising materials for artificial bone and tooth implants.This dissertation is actually a review of 4 reports with concentration on dissolution and surface complexation reactions of HAP and FAP in the lack and presence of both organic ligands and the natural and typically occurring iron oxide goethite (a-FeOOH). The dissolution and surface complexation of HAP and FAP had been researched with a mix of various strategies. Potentiometric acid/base titrations and batch experiments have been coupled with X-ray Photoelectron Spectroscopy (XPS) and Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) Spectroscopy to build dissolution and surface complexation models for both apatites. The outcomes from all of these tests indicated that both apatites form surface layers which are not the same as their bulk compositions when equilibrated in aqueous solutions…

Contents: Solubility and Surface Complexation Studies of Apatites

3. Introduction
4. Aim of the Thesis
5. Phosphorous – Geochemical Cycle
6. Phosphorous – in Teeth and Bones
7. Apatites – General Chemistry
7.1. HAP and FAP
8. Organic Ligands
9. Experimental Procedures and Technique
9.1. Mineral Synthesis
9.2. Batch Experiments
9.2.1. Dissolution of Fluorapatite in the Presence of Goethite
9.2.2. Dissolution of Hydroxy- and Fluorapatite
9.2.3. Dissolution of Hydroxyapatite and Fluorapatite in the Presence of Organic Ligands
9.3. Potentiometric Titrations
9.4. Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy
9.5. X-ray Diffraction
9.6. X-ray Photoelectron Spectroscopy
9.7. Ion Chromatography
9.8. Electrokinetics
9.9. Modeling
10. The Chemistry of Aqueous Suspensions of HAP and FAP
10.1. Dissolution, Adsorption and Phase Transformation in the Fluorapatite – Goethite System
10.2. Surface Composition of HAP and FAP
10.3. Solubility and Surface Complexation of HAP and FAP…

Source: Umea University

Download URL 2: Visit Now

Leave a Comment