Egyptian Black Sands Research Articles

Europium separation from a middle rare earths concentrate derived from Egyptian black sand monazite

Europium separation from a middle rare earth concentrate has been achieved successfully by using the combined chemical reduction–precipitation technique. The separation method depends on the reduction of europium by metallic zinc to its bivalent oxidation state followed by selective precipitation of the sparingly soluble europium (II) sulphate, while leaving the other rare earth sulphates in solution. This process consists of two steps; the first is reduction, which involves passing europium (III) chloride solution through a column packed with zinc particles. The other step involves the precipitation of the produced europium (II) chloride using a sulphate salt under inert atmosphere. Variables such as column dimensions, acidity, europium concentration in feed solution, contact time, ageing time, and concentration of the precipitating agent, have been evaluated with a pure europium synthetic solution. Based on the obtained results, a separation process was suggested for the separation of europium from a middle rare earth concentrate extracted from an Egyptian beach sand monazite. The result of this working-up is a europium yield of about 91% of the amount employed with a purity of about 97%.

Characterization of the electrical behaviour of rare earth elements during the upgrading of monazite

Electrical properties of rare earth elements (REEs) in some geological materials were characterized during the upgrading of monazite from Egyptian black sand. It has been found that there was a significant relationship between concentrations of REEs and dc conductivity. Also, dielectric constant, dielectric loss, polarization, relaxation time and resonance frequency of samples containing REEs, were measured at a frequency range up to 1 MHz. From these measurements, it has been found that the values of electrical conductivity, resonance frequency and dielectric polarization are inversely proportional to the concentration of REEs. For most relations, the correlation coefficients were found to be better than 99%.

Alkaline pressure leaching of mechanically activated Rosetta ilmenite concentrate

Hydrometallurgical processing of ilmenite concentrate separated from Egyptian black sands is attained through leaching with sodium hydroxide of mechanically activated ilmenite concentrate under relatively high temperature (200 °C) in the presence of oxygen pressure (6 bar). The effects of temperature, sodium hydroxide concentration, grinding time and oxygen partial pressure on titanium extraction were studied as well as the kinetics of the leaching process.

Cubic Zirconia from Zircon Sand by Firing with CaO/MgO Mixture.

Cubic Zirconia from Zircon Sand by Firing with CaO/MgO Mixture.

Estimation of Ra-224 Content in Egyptian Black Sand by the Can- and Alpha-Autoradiography Techniques using LR-115 Plastic Detectors

Sealed can- and alpha-autoradiography techniques were used to estimate the effective and real contents of Ra-224 respectively in Egyptian black sand samples collected from Rosetta City in the Nile Delta at the North Coast of Egypt. The effective Ra-224 content was found to be 15 ± 3 Bq · kg−1. From the average chemical composition of the black sand samples, the range-energy relation for the alpha-particles of the thorium series was calculated. Assuming radioactive equilibrium, the real Ra-224 content for samples collected from different regions were found to range from 90 to 900 Bq · kg−1. As a result, the total emanation power was measured and then used to estimate grain diameter of the black sand. The average mass exhalation rate of the different locations in Rosetta City was also estimated.