Our energy needs are encouraging us to be enthusiastic in atomic power as it is a must for our dream of strong , independent Srilanka to our future generation in the global situation.Srilanka is rich of Thorium sources that can be used for production of Uranium, a well known and widely used nuclear fuel.Thorite, Thorinite,Thorium monosite are abundant around some of coastal areas near Beruwala, Panadura,kaikawala,Ahungalla,Galle, Potuvil as well as rural areas such as Galgamuwa, Rakwana,Passara,,Mahaoya,Udawalawe and polonnaruwa.Here i discuss the effective fluid extraction- ion exchange methods that are used internToday oationally for Thorium and Uranium extraction for the use of nuclear plants and other purposes. Further reserches are required to get accurate data to consolidate whether or not above Thorium percentages are profitable for further processes.In my previous article i have described more information about above resources in Srilanka and it's possible access to nuclear power.
Thorium (Th) is a dense (11.7 grams per cubic centimeter) silvery metal that is softer than steel. It has a high melting temperature of approximately 1,750 °C (3,180 °F). Below about 1,360 °C (2,480 °F), the metal exists in the face-centered cubic (fcc) crystalline form; at higher temperatures up to its melting point, it takes on the body-centered cubic (bcc) form. Finely divided thorium metal will burn in air, but the massive metal is stable in air at ordinary temperatures .Although it will react with oxygen to form a surface tarnish.My purpose in this article to describe eligible percentages of Thorium contents to be profitable in industrial nuclear power generation and some of effective fluid ionized extraction methods as well as physical methods in Thorium extraction.
In superficial fluid extraction (sfe) of Thorium is such of method which is industrially improved fluid extraction method of Thorium where solid samples were prepared by spiking 10 micro grams each of a mixture of Uo2+ and Th4+ on p rewashed filters or sand . These filters or sand are allowed to air dry at a room temperature of 23 celcious degrees.Water samples are prepared from a 0.1Mole LiClo4 solution containing 2.5 micro gram/ml each of (Uo2)+2 and Th+4 at a ph 3.5 controlled by an acetate buffer (HAc/LiAc).A commercial extraction vessel can be used for this process and it's main body should be made from a stainless steel column and the in fittings can be obtained from swagelock.The vessel is modified for used with liquid samples (Hendrick it al 8).The chealating agent such as (Li bis(trifluoroethyl)dithyocarbomate)-LiFDDC( THIS IS NOT COMMERCIALLY AVAILABLE) but fluorinated beta-dekatones are available commercially and make stable complexes with lanthanides and actinides which are potentially useful ligands for SFE of the F block elements.Extraction and separation of actinides by superficial fluids are of particular interest today because of potential application nuclear waste analysis and management.
The chelating agent is placed in a stainless steel high pressure cylinder connected upstream of the liquid extraction vessel.The ligand cylinder and the extraction vessle is kept in an oven with the temperature controlled to +1-(-1)celcious by an omega temperature controller.A fused sillica tubing is used for pressure restriction for exit gas.In the experimental condition for the solid samples usually set duration of static extraction and same duration of dynamic flushing of Co2 ( yl/min) at 60 c and 150 atm.These conditions is found satisfactory to extract Uranyl ions from cellulose or sand base by superficial Co2.In the extraction of Actinides TTA is used as chelating agent in above conditions of temperature and pressure.
In the superficial extraction of Thorium and Uranium from nitric acid solution with organo phosphate, such a extraction techniques for the recovery of Uranium and transuranic elements from acid wastes solution are important in nuclear waste management.current technology for the removal of the Uranium and Plutonium from acidic nuclear wastes and dissolved spent fuel relies on solvent extraction with tributyl phosphate(TBP)diluted in a hydrocarbon solvent such as kerosine.Recent studies in solid and liquid materials can be effectively extracted by Co2 containing a mixture of TBP and a fluorinated beta diketone at 60c and 150 atm, while superficial Co2 modified with 30% TBP v/v at 60C and 350 atm has also been shown to extract trivalent lanthanide ions in acid solutions yielding extraction efficiency varying 61% to 92% ranges.in this extraction products of organic solvent debris are minimized.
All nitric solutions used in this method contain 50 microgram/ml each Uranium and Thorium ions.The SFE experiments includes a restrict or of stainless steel tube/ way is used to maintain the extraction pressure.The flow rate of superficial Co2 under 60 C and 200 atm with y l/min, as above i explained the main body of the liquid extraction vessel should be made of a stainless steel column and swagelock infittings.TBP placed in a liquid vessle connected upstream of the extraction vessle was dissolved in superficial Co2 by bubbling.To increase supernaturation of extract ants in fluid phase the solid phosphate oxides such as TBPO,TOPO,TPPO are place in high pressure stainless steel cell.Superficial Co2 flowed first through a cylinder containing a phospine oxides(TBPO,TOPO,TPPO) and then bubble through liquid extraction cell containing acid solution of Uranium and Thorium.superficial Co2 dissolved complex ant without opening the exit valve.After that exit valve of the extraction cell is opened and sample is extracted as well as flushed under the dynamic condition under the pressurization of superficial Co2 flowing through the cell.
When the extraction was completed , the sample was removed from the extraction cell and can analyses by nutron activation analysis(NAA). The extraction efficiency is determined by the amount of Uranium and Thorium ions remaining in sample solution after extraction divided to each elements.
Here i discussed two of fluid extraction methodes that can be used to separate Uranium and Thorium ions in soil samples or nuclear wastes liquids that can be used to manage nuclear debris as well as thorium separation.Such of fluid ionized method does not require refining or purification
Today our energy needs are encoraging us to be enthusiastic in atomic power as it is a must for our dream of , independent SriLANKA to our future generation.
Anuradha Senarathna Bsc(Hon's) , Pg dip in socio,
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