الفهرس 
Aim of the workOnly 14 pages are availabe for public view
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Abstract
Titanium is a relatively abundant element in the earth’s crust, it is usually found in igneous rocks, metamorphic rocks and beach sand placers. Titanium dioxide is used in numerous industries. Also, Ti metal and Ti alloys have several advanced uses in our modern life. Also, TiO2 has many applications in the Nuclear Industry. This should result in significant expansion of the Ti pigment, Ti metal and Ti alloys market place around the
world.
In common, TiO2 is recovered either by the sulfate process or the chloride process.
Also, TiO2 can be produced using electrodeposition techniques.
In Egypt, at Gabal Gattar (V), the huge solid waste residues, resulted after the acid leaching of the main ore material to extract uranium, are representing dangerous hazards
for the environment and contain economic and valuable elements.
This study aimed to:
1) The processing of these hazardous solid tailings to prepare titanium concentrates of high Ti-content (about 80% TiO2). It can be considered as a new resource
for rutile in Egypt.
2) The removal of the impurities accompanying titanium that harm the upgraded
rutile during subsequent processing for preparing titanium pure products.
3) To introduce a developed process for preparing titanium dioxide.
This chemical technology entails the alkaline roasting of the Ti-concentrate using alkaline flux consisted of NaOH/Na2CO3 mixture at mass ratio of (3/1). The roasted product was leached with hot water to selectively release vanadium, silica and alumina. The water leach residue (Ti-slag) was subjected to sulfuric acid leaching. The sulfuric acid leaching process resulted in a nearly complete dissolution of the water leach residue. A portion of the sulfate leach liquor was treated with NaOH solution to prepare TiO2. Another portion of the sulfate leach liquor was treated in order to recover Ti through a solvent extraction/electrochemical deposition process. The crystallography and structural transformations of all materials, residues and products were analyzed using XRD technique to reveal the crystal phase structures and the alterations for the compounds
broke down or formed in each stage during the whole technology.
The kinetics of the sulfuric acid leaching process of Ti from the roasted mass can be described by means of the Shrinking Core Model (SCM). from the results of the kinetics analysis and the Arrhenius equation, it was found that the sulfuric acid leaching of Ti is controlled by the diffusion of reactants and products through the product ash
layer and the energy of activation Ea was calculated to be 33.2 kJ/mol.