Egyptian Black Sands Research Articles

Extraction and Separation of zirconium using Aliquat 336 from Egyptian black sand

A solvent extraction method has been employed to extract and separate zirconium from the nitric acid medium using 6% tri-caprylmethylammonium chloride (Aliquat 336) [CH3(CH2)7]3N+(CH3) Cl- dissolved in kerosene as diluent. The relevant factors controlling the extraction process of zirconium using Aliquat 336 were studied. These factors include Aliquat 336 concentration, A:O phase ratio, contact time and diluent type. More than 99.6% of Zr was extracted by 6% Aliquat 336 at contact time 10 minutes, phase ratio O:A (v: v) 2:1 and the diluent were kerosene. Third phase formation was studied and dissolving it by using decanol as modifier was also done. Stripping of zirconium from loaded Aliquat 336 has been carried out using 4M H2SO4 as an effective stripping agent. The feasibility of using Aliquat 336 for separation of zirconium was assisted by stripping studies. The loaded zirconium onto Aliquat 336 has been stripped by stripping efficiency 94.18% when using 4M H2SO4 as an efficient eluting agent at 10 minutes contact time and phase ratio O:A (v: v) 1:1.

Study of smelting Egyptian black sand ilmenite by using El Magara coal

Study of smelting Egyptian black sand ilmenite by using El Magara coal

A New Approach on the Egyptian Black Sand Ilmenite Alteration Processes

Several studies have investigated the process of alteration of ilmenite, especially in black sand. To predict the mechanisms of ilmenite alteration and the role of some minor element oxides in the alteration process, separated non-magnetic altered ilmenite grains were examined using a binocular microscope and a Cameca SX-100 microprobe instrument. Twenty intergrown phases of alteration products were concluded in three postulated scenarios for the following alteration processes, carried out after forming the most stable lowest Leached pseudorutile (LPSR) phase FeTi3O6(OH)3. Most of the alteration phases of pseudorutile (PSR) and LPSR have real Ti/(Ti+Fe) ratios between 0.6 and 0.75. Some misleading calculations of definite analyzed ilmenite alteration spots showed that the analyzed TiO2 percentage is contained within the chemical formula of the analyzed LPSR phase. In these cases, the false Ti/(Ti+Fe) ratios attain up to 0.9, the false included total number of anions (O, OH) ranges between 7 and 8.5, and the associated molecular water ranged between half and two water molecules (0.5-2 H2O). In these cases, the structure of the remaining LPSR phase may be intergrown with a separated individual triple rutile phase, which appears to have the same X-Ray Diffraction (XRD) pattern as the single PSR phase, or intergrown with a cryptocrystalline TiO2 phase. Some molecular formulas of PSR or Hydroxylian PSR (HPSR) from previous studies were discussed and explained following the proposed approach.

Radiological assessment of different monazite grades after mechanical separation from black sand

In Egyptian black sands, monazite is a precious mineral characterized by its composition, which includes crucial constituents such as thorium, trace amounts of uranium, and rare earth elements. It is essential to evaluate and quantify the extent of gamma-ray exposure resulting from the presence of primordial radionuclides. This necessity arises from human activities that extract and retrieve raw materials in uranium and thorium mining operations. The current study focuses on the radiological assessment of Monazite raw material in various grades and calculates the associated hazard indices. A hyper pure Germanium detector (HPGe) determined the particular activity. For grade, 90% Monazite samples, the average activities for 232Th, 238U, and 40K were 348,008 ± 1406, 69,299 ± 2086, and 27,510 ± 245 Bq/kg, respectively. For grade 75% Monazite samples, the average activities were 219,000 ± 901, 55,000 ± 500, and 18,300 ± 86 Bq/kg, while for grade 50% Monazite samples, it was 43,294 ± 1549, 9593 ± 629, and 4000 ± 211 Bq/kg for the same element, respectively. Also, 138La’s inherent radioactivity was taken into account. The computed effective and absorbed dosages exceed the worker’s exempt limit of 20 mSv/y. The calculated hazard parameters are higher than the maximum recommended limits. Therefore, it is imperative to employ radiation safety measures to mitigate the potential hazards of ionizing radiation.

The Mineralogical and Chemical Composition of the Strongly Magnetic Egyptian Black Sand Altered Ilmenite

The Egyptian black sand contains several types of altered ilmenite grains which have various magnetic susceptibility values, ranging from the strongly paramagnetic, such as ilmenite, to the non-magnetic, such as rutile grains. The altered ilmenite grains of relatively higher mass magnetic susceptibility, separated at 0.1, 0.2, 0.25, and 0.35 A using the Frantz isodynamic magnetic separator, were investigated. Both brown and black altered grains were investigated using the binocular microscope and the Cameca SX-100 microprobe. Most analyzed spots of grains are composed mainly of pseudorutile (psr) and leached pseudorutile (lpsr), with the contents of TiO2 and Fe2O3 ranging between 56.76 and 78.09% and 37.98 and 12.16%, respectively. The Ti/(Ti+Fe) ratio ranges between 0.59 and 0.85. The chemical formula range of the investigated psr-lpsr is Fe2.07-0.54Ti3O9-4.68(OH)0-4.32. The lowest cationic iron content of the lpsr phase is 0.5 with a corresponding molecular formula of Fe0.5Ti3O4.5(OH)4.5. In the detected leached ilmenite spots, the cationic Fe2+ ranges between 0 and 2.46, while the cationic Fe3+ ranges between 0.17 and 1.94. The Ti/(Ti+Fe) ratio ranges between 0.51 and 0.6, and the Fe/Ti ratio ranges between 0.91 and 0.67. Considering the chemical formula of ilmenite is Fe3Ti3O9, the leached ilmenite formulas have the composition Fe2.72-2.02Ti3O9 with the minimum value of total iron being equal to 2.02. Some of the contained inclusions may be responsible for the acquired magnetic characteristics of some of the detected altered grains. The powdered X-ray diffraction patterns of the investigated different magnetic grains were detected before and after heating at 1100 oC for one hour. The hexagonal psr/lpsr structure is more unstable at 1100 oC than the tetragonal rutile structure. According to the calculations of the molecular formulas for the detected alteration phases, the lowest iron content of the altered lpsr is much lower than that previously reported. Also, during the alteration process, the alteration mechanism is changed in the region of 68-70 wt % of contained TiO2. Then, in the late alteration stages, the lpsr structure does not suddenly collapse but gradually produces other associated mineral phases.

Study of the Mineralogical and Chemical Compositions of the Weakly Magnetic Fractions of the Egyptian Black Sand Altered Ilmenite

One of the most extensively studied topics in dozens of studies is the alteration process of ilmenite, the formation of leucoxene, and the presence of some impurity oxides: SiO2 and Al2O3. The altered Egyptian black sand ilmenite grains of relatively lower magnetic characters are studied using the binocular microscope and the Cameca SX-100 microprobe instrument. Both individual brown- and black-altered grains separated at 0.5 and 1 ampere values are investigated. The detection of the various alteration phases, their molecular formulas and limits, and the role of SiO2 and Al2O3 in alteration mechanisms are detected. The alteration phases include pseudorutile (psr) and leached pseudorutile (lpsr) of different phases in addition to rutile. Few analyzed spots are detected to be leached ilmenite (lilm). Several Excel software are adopted to calculate the chemical formulas of each alteration phase. The contents of TiO2 and Fe2O3 of all the investigated psr/lpsr in the study are in the range of 59.16–86.56% and 37.3–6.68%, respectively. The Ti/(Ti + Fe) ratio for these formulas ranges between 0.60 and 0.88. The psr/lpsr chemical formulas of all the investigated grains range as follows: Fe2.01-0.50Ti3O8.97-4.50(OH)0.03-4.50. The concluded lowest cationic iron content of the well-defined accepted lpsr phase is 0.5 with a corresponding molecular formula of Fe0.50Ti3O4.5(OH)4.5. The results revealed that in the region of 68–70 TiO2%, the mechanism of ilmenite alteration may be changed where neither all the analyzed TiO2 of the spot nor all the calculated structural water are contained within the molecular formula of lpsr. There are other associated mineral phases containing some TiO2 and also some structural water which most probably are removed from the lpsr phase. As the analyzed spots are located at highly fissured locations, the alteration process is relatively faster and the lpsr phase can be broken into rutile and hematite. Additionally, as the analyzed TiO2 and structural and/or molecular water contents increase, the darkness of the BSE image areas of the grain increases; this may reflect the existence of an individual TiO2 phase, most probably rutile, mixed in homogeneity with the existed lpsr component. As the content of TiO2 increases, within a definite TiO2 range (80–85%), the associated contents of Al2O3 and SiO2 increase. When the contents of the structural and/or molecular water contained within the lpsr phases decreases, the total oxides sum is more than 98%, the contents of Al2O3 are highly depleted. In the late alteration stages, the lpsr structure does not suddenly collapse but gradually produces other associated mineral phases. The relatively enriched contents of SiO2 and/or Al2O3 in some secondary rutile grains can be explained as most of the SiO2% is associated with mol water or bearing for mol and/or str water necessary for the leachability of Fe3+ from the psr structure. The XRD patterns of the investigated grains before and after roasting at 1100 °C for one hour are detected and interpreted.

Synthesis of activated carbon composited with Egyptian black sand for enhanced adsorption performance toward methylene blue dye

The present study reports the feasibility of the synthesis of a novel porous composite adsorbent, prepared from olive stone activated carbon (OS400) and garnet (GA) mineral impregnations (referred to as OSMG). This composite (OSMG) was applied for its ability to adsorb a macromolecular organic dye. The composite’s structural characteristics were evaluated using various techniques such as Brunauer–Emmett–Teller (BET), Scanning Electron Microscopy equipped with Energy Dispersive X-ray spectroscopy (SEM–EDX), X-ray diffraction (XRD), and a Fourier transform infrared spectrometer (FT-IR). The specific surface area of the garnet (GA), (OS400), and (OSMG) were found to be 5.157 mg⋅g−1, 1489.598 mg⋅g−1, and 546.392 mg⋅g−1, respectively. The specific surface area of the new composite (OSMG) was promoted to enhance the adsorption of methylene blue (MB). Experiments were conducted under various conditions, including contact time, initial dye concentration, adsorbent dosage, pH, and temperatures. Data from these experiments were analyzed using several adsorption models including Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich (D-R). The results indicated that, the adsorption fit best with the Freundlich model and that the adsorption process followed a pseudo-second-order kinetic mechanism. Additionally, the thermodynamic analysis indicated the adsorption of MB onto garnet(GA) adsorbents is endothermic, while the sorption onto (OS400) and (OSMG) is an exothermic and non-spontaneous process. The OSMG composite can be used for at least five cycles without significant loss of adsorptive performance, and can easily be separated from the water after treatment.

Some Mineralogical Characteristics of the Egyptian Black Sand Beach Ilmenite Part I: Homogeneous Ilmenite and Titanhematite-Ferriilmenite Grains

The high-grade Egyptian beach ilmenite concentrate contains various mineral textures in addition to the main homogeneous ilmenite grains (63%), which may contain solid solutions of geikielite (MgTiO3) and pyrophanite (MnTiO3) mineral components. Few homogeneous ferrilmenite grains (2%) associated with the concentrated ilmenite grains are detected. The contents of Fe2O3, MgO, Al2O3, and Cr2O3 in the ferrilmenite grains range between 7.3% and 22.8%, 3.4% and 6.6%, 0.2% and 0.7%, and 0% and 1.2% respectively. The detected hematite-ilmenite exsolved intergrowths (21.4%) have titanhematite exsolutions of different shapes, sizes, and orientations. They occupy 5%-40% of the whole intergrowth and may show one or two distinct generations. In some ferrilmenite components, MnO ranges between 1.5% and 8.6%. The Cr2O3 and Al2O3 contents range between 0% and 1.2% and 0% and 3.2% respectively. They are mostly between 0% and 0.1% for either of the ferrilmenite components, while relatively greater content is present in the titanhematite components. In some grains, the titanhematite exsolution bodies are replaced by goethite or hydrated iron oxides. In others, the ferrilmenite intergrowth may be partially or completely altered into leucoxene. Some minor composite grains are detected in the concentrate, where each grain consists of two parts, one part is titanhematite-ferrimenite and the other is ferrilmenite-titanhematite. The titanhematite exsolved components have relatively lower TiO2 content (5.8%-23.8%). Both MgO and MnO are positively correlated with FeO rather than Fe2O3. The presence of sphenes in the obtained ilmenite concentrate may be responsible for the recorded amounts of SiO2 (30.1%-30.8%) and CaO (28.1% and 28.8%). The Cr2O3 content is relatively much higher in sphene spots than in ilmenite spots, ensuring that Cr2O3 neither follows TiO2 nor FeO. The nature of the problem of the relatively lower Ti content and the relatively higher Fe and Cr contents of the obtained ilmenite concentrates is the target of the article. The problem is related to the mineralogy of ilmenite or to the used physical concentration flowsheet of the separated concentrate and the ability to improve the ilmenite concentrate’s specifications. It is concluded that although the homogeneous ilmenite is characterized by low Cr2O3 content, some of the other exsolved texture components, e.g. titanhematite and sphenes, have relatively higher Cr2O3, in addition to Fe2O3, SiO2, or CaO. They can negatively affect the marketable specifications of the separated Egyptian black sand ilmenite concentrate.

Natural Radionuclide characterization on Baltim-El Burullus coastal sediments and their risk assessments

The Egyptian black sand occurs especially along the beaches of northern part of the Nile Delta. Baltim-El Burullus coastal sediments lie between Longitudes 30° 10′ and 34° 15′E, and Latitudes 31° 10′and 31° 35′N. Sixty two samples from Baltim-El Burullus coastal plain were measured radio metrically by using Na-I detector for determination of 238U, 232Th, 226Ra eU and 40K concentrations. 238U concentration ranged from 1 to 5 ppm with 1.63 as an average, 232Th from 1 to 10 ppm with average 3.66 ppm, 226Ra (eU) from 1 to 6 with 1.92 as an average and 40K from 0.10 to 2.55 with average (0.76). The studied stream sediments could be intimated to different sources, leading to variability in contribution of the radioelements, thus the activity concentration of 40K > 232Th > 226Ra> 238U. eU / Ra eU ratios average (0.66), is lower than unity indicate the disequilibrium in the studied coastal sediments, suggesting disequilibrium with uranium migration out. The inter-element relations show the presence of U and Th in discrete minerals or their separate migration. The radiological hazard parameters, like the dose rate (D), the annual effective dose equivalent (AEDE), radium equivalent activity (Raeq), external (Hex), internal (Hin) hazard indices and gamma index (Iγ) were estimated for these sediments and compared with the permissible international limits. Nearly, all the studied samples are within the recommended permissible levels for most environmental parameters, with the exception of some samples lie out of the limits.

Mineralogical Studies and Radioactivity of the Top Meter Depth of the Egyptian Black Sand, El-Dibeh, Port Said Governorate, Northern Coast of Egypt

Mineralogical Studies and Radioactivity of the Top Meter Depth of the Egyptian Black Sand, El-Dibeh, Port Said Governorate, Northern Coast of Egypt

Processing of high temperature alumina/aluminum titanate ceramic composites from clean sources

Producing new technological materials with high performance from clean sources has become a global requirement. Alumina/aluminum titanate (Al2O3/Al2TiO5) composites are high-temperature portentous materials used in various advanced applications. In this work, different Al2O3/Al2TiO5 composites were obtained with high thermal and mechanical properties for high-temperature applications by a low-cost process. The targeted composites were produced from calcined alumina and, rutile ore extracted from the Egyptian black sands by pressureless sintering at a temperature of 1650 °C/2 h. Rutile was added to alumina with a different content (0–40 wt%) to promote its sinterability and thermo-mechanical response. Evaluation of the produced composites in terms of phase composition, densification, microstructural features, mechanical and thermal properties was investigated. The results indicated that the addition of small amounts of rutile (10 and 20 wt%) succeeded in forming a stable Al2O3/Al2TiO5 composite structure. However, higher content of rutile led to the formation of Al2TiO5 rich matrix composites. Moreover, highly dense composites with harmonic microstructure and enhanced mechanical strength were attained by increasing the rutile content. The composite with only 10 wt% rutile addition gave the highest density of 3.6 g/cm3 and the highest cold crushing strength and modulus of rupture values of 488.73 MPa and 106.19 MPa, respectively. Notably, the addition of rutile has a substantial effect on promoting the thermal properties and thermal stability of the obtained composites up to a high temperature of 1400 °C. The present study shows that addition of rutile ore to alumina is one economical way of improving the densification and thermal expansion of Al2O3 for high temperature applications. Using a clean source such as rutile ore that contains some thermal stabilizers as Fe2O3, Al2O3, SiO2, ZrO2, and MgO instead of pure TiO2 has played a noticeable role in improving the reaction sintering and resulting in a highly qualified material. Thus, sintered Al2O3/Al2TiO5 composites can be considered as a promising high-temperature material for advanced applications.

STUDYING THE COST AND BENIFIT TO INCREASE THE ADDED VALUE OF THE ILEMENIT MINERAL EXTRACTED FROM THE EGYPTIAN BLACK SAND USING A SHREDDER

The researchers aim to shed light on the economic importance of the Egyptian black sands and the economic minerals extracted from them, and to determine the global and Egyptian reserves from them. The study also deals with raising the added value of ilmenite extracted from Egyptian black sand in order to produce ferotitanium alloy, and prepare an integrated vision to determine the possibility of establishing industrial projects to raise the economic value of ilmenite through the application of methods used in rationalizing costs, using the descriptive analytical method in order to increase the national product accordingly. This study was applied to the black sands of the Rosetta site in the North Delta, which is one of the field work sites of the Nuclear Materials Authority. Ferrotitanium alloy is one of the most widely used alloys in the steel and stainless steel industries, the paint industry, and the missile and aircraft industry. The study concluded that it is possible to increase the revenue generated from the production of ferotitanium alloy and raise the economic added value of ilmenite by using raw materials in different mixing methods that lead to rationalization of costs, achieving sustainable development goals and increasing national income. The researchers recommend expanding the application of the proposal to use the shredder machine in extracting the aluminite metal due to the rationalization of costs, an increase in the revenue, and raising the added value of the aluminite mineral, the need to maintain the quality of production and the introduction of continuous improvements to rationalize the indirect costs, as well as the necessity to supply the Nuclear Materials Authority with supplies, tools and devices used in the exploration of black sand areas throughout Egypt, and the use of fuel derived from solid waste plastic (RDF) instead of natural gas to save energy costs.

Economic and Environmental Study for Added Value of Separation, Treatment and Process of Egyptian Black Sand Monazite Practical Study (Nuclear Material Authority)

Economic and Environmental Study for Added Value of Separation, Treatment and Process of Egyptian Black Sand Monazite Practical Study (Nuclear Material Authority)

Evaluation of the use of Egyptian black sand for water reuse

The presented article refers to studies that examined the catalytic properties of black sand (AR Egypt) for its further use in water purification in fishery complexes. Also, black sand was used as a filter material in a radial filter model. According to experimental data, the stated hypotheses were confirmed.

Preparation of La2Zr2O7 ceramic from Egyptian black sand

Lanthanum zirconates has been suggested as a thermal barrier coating for many high temperature applications. This work is focusing on the possibility of La2Zr2O7 from economic natural resources using Egyptian monazite and zircon. For this purpose, the prepared product of monazite REEs concentrate was subjected to Ce separation by its oxidation and precipitation as Ce (IV) at pH 3 with contact time 15 min and 30% excess amount of KMnO4. The REE-cake almost free from Ce (IV) was passing through Dowex50X8 cation exchange resin for the separation of pure product of La2O3. A homogeneous single phase compound of La2Zr2O7 has been formed at 3 h sintering time with sintering temperature 1100 °C and ZrO2/La2O3 ratio 50% this confirmed with XRD (X-ray diffraction), Raman and EDX analysis techniques.

Study of some requirements of the environmental management system at the test-work facilities of the Egyptian black sands at Abu Khashaba and Rasheed.

30May 2016 Study of some requirements of the environmental management system at the test-work facilities of the Egyptian black sands at Abu Khashaba and Rasheed. Abdel-Razek , Y. A. , Abu-Diab , A. A. , El-Kassas , H. I. , El Miniawy , Aisha M. and Bakhit , A. A. Nuclear Material Authority. Cairo, Egypt, P.O. box 530, El Maadi, Cairo. Institute of Environmental Studies & Research- Ain Shams University, El Abbasiya, Cairo, Egypt. Faculty of Commerce – Ain Shams University, El Abbasiya, Cairo, Egypt.

Distribution of Some Elements in the Egyptian Black Sands from Abu Khashaba Beach Area

Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) technique was used to determine the concentrations of titanium (Ti), vanadium (V), Chromium (Cr), Manganese (Mn), iron (Fe), zinc (Zn), arsenic (As), zirconium (Zr), cadmium (Cd) and hafnium (Hf) in black sands samples. 18 black sands samples were collected from the Mediterranean coast-Abu Khashabou Rosetta area, Egypt. Alkaline fusion procedure using mixture of Li-meta borate and tetra borate was used for the digestion of black sands samples. The average concentrations of Ti, V, Cr, Mn, Fe, Zn, As, Zr, Cd and Hf were 435.06 ppm, 322.32 ppm, 2515.03 ppm, 596.45 ppm, 185894 ppm, 249.95 ppm,309.32 ppm, 1077.26 ppm, 33.56 ppm and 3520.32 ppm, respectively. The procedure was tested with Basalt Hawaiian Volcanic Observatory (BHVO-2) standard reference material.

Mineralogical Characteristics of the Separated Magnetic Rutile of the Egyptian Black Sands

AbstractThe Egyptian black sands contain several economic minerals, such as ilmenite, magnetite, garnet, zircon, rutile and monazite. During the concentration and separation of a high‐grade rutile concentrate a bulk magnetic fraction is obtained. This fraction is composed mainly of opaques, titanhematite, ilmenite–titanhematite exsolved intergrown grains, magnetic leucoxene in addition to chromite, and magnetic rutile. The magnetic rutile occupies 6 wt.% of the bulk magnetic fraction or approx. 4 wt.% of the original rutile content in the raw sands. Most of magnetic rutile crystals are contaminated with opaque inclusions, staining‐coating and/or composite locked grains. This magnetic rutile has a magnetic range from strongly paramagnetic to very weak paramagnetic. Electron microprobe analysis for twenty‐three magnetic rutile grains identified mineral components of rutile, titanhematite, pseudorutile, leached pseudorutile and ilmenite in decreasing order of abundance. Some other inclusions are also detected in the different magnetic rutile grains. They are most probably garnet, silica, amphibole, ilmenite, feldspar, mica and zircon. The presence of these inclusions reflect the derivation of magnetic rutile of various crystalline igneous and metamorphic rocks. The magnetic susceptibility of magnetic rutile depends on the associated mineral components and their relative volumes in comparison to the rutile mineral component. Magnetic susceptibility of magnetic rutile is also related to both type and size of the associated mineral inclusions. The average chemical composition of the magnetic rutile is 66.34 wt.% TiO2, 21.71 wt.% Fe2O3, 6.39 wt.% SiO2, 1.80 wt.% Al2O3, 1.19 wt.% CaO and 0.10 wt.% Cr2O3. Thus, the contamination of magnetic rutile in the non‐magnetic rutile concentrate would decrease the market value of the rutile concentrate. Alternatively these magnetic rutile grains are recommended to be blended with magnetic leucoxene or some types of ilmenite concentrate to improve the overall marketable specifications especially for both of Ti, Fe and Cr contents.

Physical and Chemical Beneficiation of the Egyptian Beach Monazite

AbstractThe Egyptian black sands contain several economic minerals, especially ilmenite. Monazite can reach concentrations up to 0.6 wt.%. The majority of monazite grains have light to deep canary and lemon yellow colors, whereas enigmatic monazite grains have brown, red, resinous, yellow and colorless to pinkish colors. The behavior of monazite with the electrostatic field setting of the roll‐type electrostatic separator was studied for the different variables of the separator. Most of the monazite grains are reversible negative and are attracted towards the positively charged static electrode. Using wet gravity concentration, both low and high intensity magnetic separation, and electrostatic separation techniques, a high grade concentrate assaying 97 wt. % monazite with a recovery of 76.8% can be obtained.The Egyptian beach monazite contains high concentrations of Ce, La and Nd in addition to minor amounts of Y, Pr, Sm, Gd, Dy and Eu. It is particularly rich in the lighter rare earth elements (cerium subgroup). By a new method of ion exchange technique after chemically dissolving the mineral with sulfuric acid, both of REEs, Th and U, could be individually separated. The efficiency of the separation has been tested with sulfuric acid concentration at 2M H2SO4 where the thorium and uranium could be obtained with a cation exchange synthetic resin column, while rare earth metal ions are adsorbed and then individually separated. A highly pure thorium product could be obtained by oxalate precipitation followed by uranium precipitation as diuranate using NaOH.

Contribution to the external surface of a titanium-rich sand (Abou-Khashaba, Egypt) in the uranium uptake processes

The present study reports the U(VI) uptake from solution on a Ti-rich Egyptian black sand, showing that the crystal surfaces exhibit a marginal influence to the total process of U(VI) uptake onto Ti-containing micro- and mesoporous silicate materials. The results were evaluated using Lagergren first order equation and the apparent thermodynamic parameters of uranium uptake onto the considered materials were calculated.