The prepared amine-impregnated cellulose (AIC) was found to be an efficient adsorbent for uranium originated from El-Sebaiya phosphate ore. The impregenation process was carried out by copolymerization between pretreated cellulose and a mixture of (tri-ethyl amine and epi-chorohydrine).In the present work, two working solutions were used. The first solution was a synthesized phosphoric acid (35% P 2 O 5 and 100 ppm U) used for optimizing the loading process of uranium. The second one was used as a case study for adsorption of uranium from a real phosphoric acid (WPPA) prepared from El-Sebaiya phosphate ore (P 2 O 5 35%, 100 ppm U).The obtained equilibrium data were found to be satisfactory fitted with Langmuir isotherm.A maximum-metal uptake of 56.5 mgU/g AIC was observed at the obtained optimum conditions. Also, elution process of uranium has been achieved at 1 M of 30 ml Na 2 CO 3 solution/g AIC after 15 min contact time. From the latter, a marketable product of sodium di-uranate was prepared.
To avert excessive sulfuric acid exhaustion in the classical leaching procedure and to avoid leaching of other undesirable impurities, proper alkaline leaching has been achieved for dolostone of Gabal Allouga, Southwestern Sinai, Egypt. The relevant factors for alkaline leaching of a technological sample assaying 1.2% Cu and 0.15% U were examined using a mixture of Na 2 CO 3 / (NH 4) HCO 3 solution upon two samples namely; roasted sample at 540°C and raw materials un-roasted. The leaching kinetic results showed that the leaching procedure of uranium and copper from dolostone is controlled by shrinking core kinetic model 1-2/3(X)−(1−X) 2/3 = k d t.
Lanthanum zirconates has been suggested as a thermal barrier coating for many high temperature applications. This work is focusing on the possibility of La 2 Zr 2 O 7 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 KMnO 4. The REE-cake almost free from Ce (IV) was passing through Dow-ex50X8 cation exchange resin for the separation of pure product of La 2 O 3. A homogeneous single phase compound of La 2 Zr 2 O 7 has been formed at 3 h sintering time with sintering temperature 1100 C and ZrO 2 /La 2 O 3 ratio 50% this confirmed with XRD (X-ray diffraction), Raman and EDX analysis techniques.
The quartz vein cutting the granodiorite of Ras Abda, along the western shear zone, exhibits high radioactive potentiality (up to 3000 ppm for Th and 1600 ppm for U. The microscopic investigation of the quartz vein revealed that it is composed mainly of quartz and iron oxides enclosing squadrons of the accessory minerals. Granitic fragments are corroded and digested from the wall-rock affecting the chemical composition of the studied rock. Chemically, it is characterized by low alumina and medium potassium contents with peralkaline affinity. It is also characterized by high concentrations of the trace elements (Zr >10000, Nb 3481, Y 8621, U 903 and Th 2340 ppm) and the total rare earth elements (up to 24246 ppm) specially the HREEs with very low degree of fractionation in the melt (0.014) and in turn, high degree of fractionation in the accessory minerals. The mineralogical investigation using ESEM and XRD techniques revealed the minerals are responsible for the radioactivity in the anomalous rock such as zircon, thorite, uranothorite and Nb-Ta minerals (columbite, euxenite and uranopolycrase). Experimental work in this study agreed with the previous experiments and concluded that metamictization is attributed to the heat of self-annealing that responsible for transformation of U-euxenite to metamictized euxenite and transformation of Ti-U-euxenite to metamictized uranopolycrase. The present study concluded that the studied quartz vein originated from silicic magma rich in the trace and rare earth elements; hence it is considered as good hostile for the radioelements and possesses high radioactive potentiality.
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