There are three ways of removing radioactive nuclides using zeolites:

METHOD 1. CATION EXCHANGE. “Zeolite” refers to a group of minerals that are basically hydrated calcium potassium sodium alumina-silicates in which the water is held in cavities and in the lattice.  The lattices are negatively charged and they hold cations. Their ability to exchange one cation for another is known as their “cation- exchange capacity or “CEC.”  Cation-exchange capacity is a measure of the number of cations per unit weight available for exchange, usually expressed as mill equivalents per 100 grams of material.  

As a result of its high cation exchange capacity, BRZ is able to exchange various cations into its lattice depending on their molecular size, competing cations, and concentrations. In the lattice, they are not water soluble. Following is a list of some of the cations:

METHOD 2. SURFACE MODIFIED ZEOLITE (SMZ).

Often some of the radioactive isotopes are compounded with anions. To remove them, the surface charge of BRZ can be modified to a positive charge to exchange anions into the lattice. It is called a “surface modified zeolite” or “SMZ”. The anions would include bicarbonates (HCO3-1), carbonates (CO3-2), sulphates (SO4-2), sulfites (SO3-1),   chlorides (CL-1), arsenates (As-1), nitrates (NO3-1), nitrites (NO2-1), and phosphates (PO4-3).  The modifier is typically a quaternary amine.

METHOD 3. CATION EXCHANGE IN SERIES WITH SMZ.

This method also may have the advantage of removing arsenates and other undesirable compounds/elements.

METHODS OF APPLICATION

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REACTOR SITES.  Contaminated ground must be excavated and removed to a HAZMAT site. Merely covering the site will not remove the radioactive nuclides.

PERMEABLE TREATMENT WALLS (PTWs).

PTW’s should be installed down-stream from the source of contamination to stop the migration of contaminated groundwater. These involve digging a trench up to 4 foot wide and 0-40 deep and filling it with 14 x 40 BRZ zeolite. PTWs are very effective for shallow ground water migration.

PUMP BACK SYSTEM. Pump back wells are drilled down-stream of nuclear sites where the migrating groundwater is too deep to access with a PTW. The water is pumped back up gradient and filtered through a gravity bed or pressure filer filled with 14 x 40 BRZ.  

WATER FILTRATION PLANTS.  Sand and anthracite filter media in municipal plants should be immediately replaced with BRZ to remove radionuclides. Typically 14 x 40 would be used.

DOMESTIC AND COMMERCIAL FILTRATION.

RRZ should be made immediately available to domestic and commercial facilities for the removal of radionuclides in the washing of clothing, milk, any liquid food products, etc.

HUMAN CONSUMPTION.  Children and adults should be put on a steady diet of clinoptiolite. This involves very small amounts usually less than 1% by weight of the average daily diet. The BRZ will chelate the radioactive nuclides and they will pass from the body.

ENCAPSULATION OF NUCLEAR WASTE.  All nuclear waste removed from contaminated areas, filtration media, etc. should be encapsulated with BRZ. Permanent encapsulation would involve mixing the contaminated material and BRZ with Portland cement and storing it at HAZMAT sites.

REVISITING THE HISTORY OF SOME APPLICATIONS 

CHERNOBYL, UKRAINE,1986

The Chernobyl meltdown is probably the largest electric nuclear generating plant catastrophe. Reportedly the Russians used 450,000 metric tons of clinoptiolite to eventually bury the reactor to a depth of more than 100 feet. Little is known about the levels of radiation prior to or after the remediation. More than 93% of the radiation was generated by isotopes of Cs and Sr. “The addition of zeolites to soil reduced the supply of radionuclides to plants by a factor of 2-3 times for 137Cs by 50-70% for 90Sr. The use of zeolite dietary additions to polluted fodder (1-3 games zeolite/kg of body weight) reduced the concentration of radio nuclides in meat by factors of 2 to 3 and in milk, by factors of 5 to 7. Natural clinoptiolite has been successful in removing radioactive nuclides from the human body.” (Nikolai F. Chelishochev)   The Russians countered the Sr-90 in children by feeding each one of them a chocolate cookie per day containing zeolite. The zeolite removed the 90Sr from ingestion by the children. They also remediated other food products, sewage, laundry waste (using zeolite detergents); animal feeds, and prepared zeolite drugs for humans.

WEST VALLEY DEMONSTATION PROJECT, WEST VALLEY, NEW YORK, 2010. 

In 2010, BRZ was chosen by the U. S. Department of Energy for the remediation of the West Valley Demonstration Project near Buffalo, New York.  This was an old Westinghouse fuel rod processing facility that sprung a 90Sr leak some 30 years ago underground that contaminated the groundwater in a large plume. They dug a trench some 580 feet long to a depth of approximately 30 foot with a width of 3 foot and placed more than 2,460 metric tons of 14 x 40 BRZ in it. This was a permeable treatment wall or “PTW”. BRZ was chosen over all other domestic zeolites after extensive laboratory testing. Final testing of the groundwater below the PTW has shown that the 90Sr has been removed to below the detection level. The PTW is expected to last 20 years before a break-through.

FUKUSHIMA, JAPAN, 2014

This is a generalized synopsis of what we believe is happening in the wake of the nuclear event in Japan.

 Five nuclear reactors are in a melt- down stage. The containment structures of each reactor have been breached. Nothing can be done until the melt down has been completed, and this will be on the order of 30 years. At that point, the seawater must be washed out with fresh water. Zeolite will not work as well with the sodium presence in the seawater. It will exchange with the sodium first and will exchange only minor amounts of the radionuclides. Preliminary estimates are that more than 90,000,000 tons of zeolite will be needed to cover the reactor sites and to place PTWs. The zeolite should be accrued during this 30-year period.

 Massive amounts of seawater are being applied to each reactor to cool them down. The seawater is returning to the ocean with the radionuclides. Seawater is being used, because the amount of water needed far exceeds the available fresh-water supply in Japan.

Radioactive elements have been spread by airborne methods in stream and air, by natural flowing groundwater, and by the application of the seawater. Tokyo Electric Power Company (TEPCO) has reported the release of 137Cs with a half-life of 30.1 years and 131I with a half-life of 8.0 days in the seawater being returned to the ocean. The ratio of 131I/137Cs has indicated that there has not been any significant chemical fractionation between the two isotopes prior to their release into the ocean other than the decay of 131I. Most of the iodine produced in fission reactions are short-lived isotopes such as Iodine 131I.  The only radioactive isotope of iodine with a long half-life produced in a fission reactions is 129I, and it has a half- life of 15.7 MY.  Only 0.65% of all the isotopes produced in a fission reaction of 235U are 129I and it is not a high-energy radioactive source.  Consequently, iodine is not as high on the priority list as 137Cs, 90Sr or 89RB for remediation. They all are high energy radioactive sources with moderately long half lives and make up a large percentage of the isotopes produced in a fission reaction. Unofficially we have heard that 90Sr is also being released. Although the chemistry becomes very involved, 90Sr is symptomatic of a cool down. It is particularly bad, because it will replace Ca especially in adolescent bones and teeth.

Polluted areas include (1) the point source reactor areas themselves, (2) the ocean seawater, (3) inhabited areas including playgrounds, (3) farmlands, (4) forested areas, (5) a section of beach 300 kilometers long and 3 kilometers wide, and (6) more important the area of contamination may be spreading on a world-wide basis.

CHALK RIVER TO ONTARIO, CANADA, 2012 AND 2013

In 2012 and 2013 BRZ shipped 808 metric tons for the remediation of Chalk River, Ontario in. (Enter picture only). The first reactor meltdown occurred in 1952 when the cooling system failed. The cooling rods could not be lowered into the core and spent fuel rods overheated and released radiation that contaminated 4,500 tons of water in the basement. Hydrogen explosions accompanied the melt down. The water was dumped in nearby ditches that created a plume up to 1,600 meters from the Ottawa River.