scholarly journals Mineralogical Investigation and Hydrometallurgical Characteristics of Uranium and Rare Earth Elements, Mineralization of El Hammamat Sediments, G. Gattar, Eastern Desert - Egypt

2016 ◽  
Vol 2 (3) ◽  
Author(s):  
El Nahas, H.A., Abd-El fattah, N. A., El Monsif, M. Z
Keyword(s):  
Clay Fraction ◽  
Acid Leaching ◽  
Eastern Desert ◽  
Chemical Processing ◽  
Light Elements ◽  
Uranium Deposits ◽  
Uranium Mineral ◽  
Oxalate Precipitation ◽  
Technological Sample ◽  
Two Alternatives

The uranium occurrence of GV is considered as perigranitic uranium deposits while all the others are considered as intragranitic ones. The principal economic minerals were separated and identified. Uranophane was found to represent the main uranium mineral while the REEs occur in the form of very fine disseminated grains of light elements or else in the form of heavy elements associated with the iron oxides and clay fraction of the host rock. For geochemical and hydrometallurgical works, a technological sample of (4000ppm U and 3500ppm REE) at the Northern part of the Eastern Desert, Hammamat GV mineralization of G. Gattar was collected. The collected ore material was then subjected to chemical processing involving sulphuric acid leaching and the dissolved U and REE were separated from the obtained leach liquor. Two alternatives have been studied, namely ion exchange for U following oxalate precipitation for the REEs or else selective successive precipitation.  

Chemical Processing of BaTiO3 Based ceramics

1986 ◽  
Vol 72 ◽  
Author(s):  
J. L. Rehspringer ◽  
J. C. Bernier
Keyword(s):  
Dielectric Properties ◽  
Chemical Processing ◽  
Grain Sizes ◽  
Oxalate Precipitation

AbstractFor multilayers capacitors, submicron BaTiO3 powders are synthetised by chemical routes including gels. Three routes are described, oxalate precipitation, alkoxide gels and carboxyalkoxide polymerisations. Powders characteristics, relations between grain sizes, agglomerates, sintering capabilities and dielectric properties are discussed

scholarly journals ACID LEACHING OF URANIUM FROM KAOLINIZED GRANITE OF EL SELA AREA, SOUTH EASTERN DESERT, EGYPT

2017 ◽  
Vol 6 (1) ◽  
pp. 181-190
Author(s):  
MOHAMED DEMERDASH ◽  
REDA GHAZALA ◽  
MONA FAWZY
Keyword(s):  
Acid Leaching ◽  
Eastern Desert ◽  
South Eastern

scholarly journals Acidic heap leaching behavior of uranium from El-Sela area, South Eastern Desert, Egypt

2021 ◽  
Author(s):  
Mohamed S Nagar ◽  
Walid M Morsy
Keyword(s):  
Particle Size ◽  
Fine Particles ◽  
Acid Leaching ◽  
Eastern Desert ◽  
Leach Solution ◽  
Order Kinetic ◽  
Agglomeration Effect ◽  
Dissolution Efficiency ◽  
Kinetics Of ◽  
Leaching Efficiency

Abstract The column percolation technique was used to examine the leachability of uranium from El-Sela uranium mineralization. The agglomeration effect, particle size, flow rates, acid concentration, solid to liquid ratio, and sand agglomeration effect were all studied in the kinetics of uranium leaching. The acidic leach solution causes alteration and thus dissolves the oxides that fill joints and fractures, resulting in a reduction in ore particle size, as well as the swelling of fine particles caused by acid leaching over time. As a result, the focus of this research is on the possibility of increasing the permeability of ore heaps by adding cobblestone. At a height of 3.0 m within the column, the optimal ratio of cobblestone to ore was found to be 1:4, and the irrigation rate was reduced from 0.15 to 0.1L/ m2/min, increasing the uranium dissolution efficiency from 47.5 to 79 percent. Finally, the column leaching efficiency is confirmed by fitting data from an application first-order kinetic law with data collected.

U series age and origin of two secondary uranium deposits, central Eastern Desert, Egypt

1999 ◽  
Vol 94 (2) ◽  
pp. 273-280 ◽  
Author(s):  
J. K. Osmond ◽  
Adel A. Dabous ◽  
Yehia H. Dawood
Keyword(s):  
Eastern Desert ◽  
Uranium Deposits ◽  
Central Eastern Desert ◽  
Central Eastern

scholarly journals Towards the Circular Economy of Rare Earth Elements: Lanthanum Leaching from Spent FCC Catalyst by Acids

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1369
Author(s):  
Corradino Sposato ◽  
Enrico Catizzone ◽  
Alessandro Blasi ◽  
Marilena Forte ◽  
Assunta Romanelli ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Information And Communication Technologies ◽  
Market Price ◽  
Acid Leaching ◽  
Soil Extraction ◽  
Spent Fcc Catalyst ◽  
Fcc Catalyst ◽  
Oxalate Precipitation ◽  
The Impact

Rare earth elements (REEs) are strategic materials widely used in different applications from Information and Communication Technologies (ICT) to catalysis, which are expected to grow more in the future. In order to reduce the impact of market price and reduce the environmental effect from soil extraction, recovery/purification strategies should be exploited. This paper presents a combined acid-leaching/oxalate precipitation process to recover lanthanum from spent FCC catalyst using nitric acid. Preferred to hydrochloric and sulphuric acid (preliminary assessed), HNO3 showed a good capability to completely leach lanthanum. The combination with an oxalate precipitation step allowed demonstrating that a highly pure (>98% w/w) lanthanum solid can be recovered, with a neglectable amount of poisoning metals (Ni, V) contained into the spent catalyst. This could open a reliable industrial perspective to recover and purify REE in the view of a sustainable recycling strategy.

Scattering-angle dependence of signal/background ratio of inner-shell electron excitation loss in EELS

1983 ◽  
Vol 41 ◽  
pp. 390-391
Author(s):  
T. Oikawa ◽  
M. Inoue ◽  
T. Honda ◽  
Y. Kokubo
Keyword(s):  
Energy Loss ◽  
Electron Excitation ◽  
Heavy Elements ◽  
Background Intensity ◽  
Light Elements ◽  
Energy Analyzer ◽  
High Background ◽  
Scattering Angle ◽  
Angle Dependence ◽  
Shell Electron

EELS allows us to make analysis of light elements such as hydrogen to heavy elements of microareas on the specimen. In energy loss spectra, however, elemental signals ride on a high background; therefore, the signal/background (S/B) ratio is very low in EELS. A technique which collects the center beam axial-symmetrically in the scattering angle is generally used to obtain high total intensity. However, the technique collects high background intensity together with elemental signals; therefore, the technique does not improve the S/B ratio. This report presents the experimental results of the S/B ratio measured as a function of the scattering angle and shows the possibility of the S/B ratio being improved in the high scattering angle range.Energy loss spectra have been measured using a JEM-200CX TEM with an energy analyzer ASEA3 at 200 kV.Fig.l shows a typical K-shell electron excitation edge riding on background in an energy loss spectrum.

Sign in / Sign up

Export Citation Format

Share Document