A new sorbent, thorium oxalate incorporated in silica gel matrix was prepared. This material was characterized by X-ray, Thermo-gravimetric
Analysis, surface area and porosity analysis. The material was obtained in the form of granular particles in the mesh size
range of 80–150 American Standard of Testing Materials, yielding good liquid flow, when packed in ion exchange column. This
sorbent was investigated for the sorption of americium from various aqueous media such as nitric acid, oxalic acid and sulphuric
acid by distribution coefficient studies. Column experiments were carried out to study the practical application of this sorbent
for removal of americium from oxalic acid-nitric acid solutions. Elution studies were also carried out for the recovery of
promise recently. At present, adsorption is one of the promising methods for CO 2 capture from flue gas. Many solid sorbents have been, or are currently being, investigated, such as activated carbons [ 2 – 4 ], zeolites [ 3 – 7 ], coal [ 8 ], fly ash [ 9
sorbents and hybrid materials. Particularly often used mineral substances of highly developed surface are silica and alumina while among organic substances are both chemical compounds of defined composition like acenaphthene, naphthalene, formaldehyde
Literature references present the possibilities of use of various mineral and carbon substances to produce complex sorbents. Often used mineral substances of highly developed surface are silica and alumina while
Inorganic sorbents are often used in separation of metals and radionuclides in radioanalytical application and they were also used in technological scale for separation of radionuclides in cleanup of Three Mile Island NPP. Inorganic sorbents become popular in the last years because no problem with organic contamination, there are stable against radiation, sorption efficiency can be tailor made for selective separation of chosen metal. Contrary to the organic sorbents they have usually lower capacity and chemical stability is limited to narrower pH. Nevertheless of some problems, many good properties of inorganic sorbents make them very attractive for sorption study.
A modified sorbent for99mTe generators of higher activities has been developed. The sorbent consists of two layers. The layer in which (F.P.)99Mo is adsorbed contains alumina and silica gel mixture in the weight ratio 4060%. The underlaying layer contains 0.5% g of pure alumina. The performances of the columns filled with this sorbent are compared to these containing pure alumina with respect to the total elution efficiency of99mTc and the elution efficiency ratio of subsequent elutions. Radiochemical and radionuclidic purities (99Mo breakthrough) of eluates from both kinds of columns have also been determined and compared.
The properties of a composite ion exchanger containing potassium nickel ferrocyanide incorporated in silica gel matrix are described. The sorbent was prepared in the form of spherical beads. For the characterisation of the ion exchanger X-ray diffraction, electron microscopy, IR and Mössbauer spectrometry were used. The sorbent was used for the sorption of radiocesium from model solutions as well as from radioactive waste solutions (NPP Jaslovské Bohunice, Slovakia).
The history of sorption and ion-exchange processes starts with the use of natural materials which properties were discovered
coincidentally and ends with the age of polymer and anorganic—or synthetic sorbents specifically made for a particular project.
Its objectives are focused on sorption of anthropogenic radionuclides originating from nuclear power plant operations (fission,
activation, corrosion products and transuranium elements) on bentonites, zeolites, hydroxyapatites, magnetic sorbent, ferrocyanides,
and silica sorbent. Bentonites from Slovak deposits should be used as part of multi-barrier system in deep geological repository
for spent nuclear fuel and high level radioactive waste. Zeolites are used as molecular sieves, catalysts, ion-exchangers,
sorbents, water softeners, in wastewater treatment, in chemistry industry, buildings. Hydroxyapatite is a suitable sorbent
for heavy metals and radionuclides due to its low water solubility, high stability under reducing and oxidizing conditions,
high specific surface area and good buffering properties. The leaching wastes from the Sereď hydrometallurgical plant represent
a large stock of inexpensive, ready-to-use magnetic sorbent for the decontamination of soil or sediments in their common suspensions,
followed by the magnetic separation and sorbent recycling. Insoluble ferrocyanides of nickel are highly selective sorbents
for heavy alkali metals ions, and therefore can be used to separate cesium from liquid radioactve waste. Silica sorbents modified
with imidazole can be used for the separation of cobalt ions from aqueous solution.
Composite sorbents based on potassium nickel ferrocyanide embedded in silica gel matrix were prepared and characterised by
powdered X-ray diffraction analysis, IR spectra, Mössbauer spectra and electron microscopy. The sorbent exhibits very good
efficiency for cesium uptake and radiation resistance. The sorption capacity for cesium ions is comparable with the capacity
for the pure ferrocyanides.