The 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 H 2SO4 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.
Rare earth elements concentrate (REEs) which has been prepared from Rosetta monazite assays 44, 23, 16.94 and 5.91% for Ce, La, Nd and Pr, respectively. Highly pure individual separation of Pr(III) from this concentrate was achieved using a cationic Dowex 50W-X8 ion exchange resin. An EDTA solution assaying 0.015 mol L −1 was used for the complete REEs elution. In this study, the proposed method was applied for the determination of individual Pr(III) after the separation of Ce(IV) by oxidation at 200 °C and separation of Pr(III) from REEs concentrate via ion exchange. Simple perchlorate method was applied at the achieved optimum conditions for the separate spectrophotometric determination of Pr(III) at λ max 444 nm using the fourth derivative spectrum. A fourth derivative molecular absorption spectrophotometric was used to overcome the overlapped interfering spectra to determine the individual components.
Wadi (Valley) Nasab (WN) and its surroundings, is an area of mining located at the southwestern Sinai, Egypt for some heavy metals and radioactive elements from Lower Carboniferous. This activity represent a source of environmental contamination. This contamination is the main target of this study. Ore material, solid wastes and soil samples were collected from 10 stations. Whereas, plants samples were collected from two types of herb weeds (i.e., Zygophyllum siplex and Haloxylon salicornicum) from WN and its surroundings southwestern of Sinai. The original ore material is chemically consisted of around 50% SiO2, 10.6% Al2O3, 10.2 Fe2O3, 13% (CaO + MgO) and around 10% loss on ignition. This figure means high carbonate and total iron contents. The mineralogic constituents of solid waste are consisted of Quartz, Kaolinite, Jarosite and Gypsum. The milling waste contains 60.2% SiO2, 6.8% Al2O3, 9.4% Fe2O3, 4.7% (CaO + MgO) and 14.8% loss on ignition. The picture of some trace elements is as follow; Cu is 2900 ppm in ore materials and 359 ppm in milling waste. In the same order, Zn is 1865 and 92 ppm, Th is 14 and 26 ppm, U is 346 and 184 ppm, Ra 226 is 135 and 179 Bq/ kg. This picture of ore material and milling waste is reflected on the soil profile after the flash flood. The degree of contamination is pronounced in the upstream water of W. Nasab and decrease in the direction of downstream. Thorium (Th) ranged from 5 to 13 ppm at the upstream and from 4 to 5 ppm in the downstream. On the other hand, U ranged from 5 to 9 ppm in the upstream and from 2 to 7 in downstream. The contamination effect is also clear in two types of Herb weeds of WN. Uranium in roots of (Zygophyllum siplex) plant, ranged from 4 to 6 ppm while in roots of (Haloxylon salicornicum) plant was not detected. Also, it was not detected in the vegetable parts of the two herb plants and Th was not detected in roots and the vegetable parts of the two herb plants.
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