CC3 is a New Material That Can Trap Radioactive Gases

         We usually think of radioactive contamination in terms of solid radioactive elements such as uranium and plutonium. However, there are also radioactive gases such as radon. This gas is created as naturally occurring uranium decays. In some parts of the country, natural radon can accumulate in basements and pose a health threat. When nuclear fuel is burned in a reactor, radioactive isotopes of xenon and krypton are generated. Radon, krypton and xenon are members of the noble gases in the periodic table of elements. Noble gases do not normally interact and form compounds with other elements. These three gases pose a human health threat and it is very important for us to develop an efficient and cost-effective way to remove them from air and water.

         A recent research report details how a newly discovered material is more efficient at removing radioactive gases from the atmosphere and water than any other material known. The new material is called CC3. There is an artist's rendering of the CC3 molecule at the bottom of this post. The capability of CC3 to trap noble gases is surprising because of the normally non-reactive nature of these gases.

        The standard method of removing noble gases from air depends on cooling the air far below freezing. Because this process is complicated and expensive, scientists have been searching for an alternative. One avenue of research has focused on metal-organic frameworks (MOFs) that might be able to trap noble gases without the cooling now necessary. They did find MOFs that could remove noble gases in low concentrations at room temperature but they continued searching for a more efficient alternative.

        A different approach to capture of noble gases focused on what are called porous organic cages. These materials have a repeating three dimensional structure that forms "cages" that could hold atoms of xenon, radon or krypton. CC3 has cages that are just about the right size for these noble gas atoms. Computer simulations show that the cages open and close by about twenty percent. They are only open fully about seven percent of the time but that is enough for xenon atoms to enter. Xenon atoms are more likely to enter an empty cage than to leave a cage. This makes CC3 an excellent material to trap noble gases.

        The researches took a piece of CC3 and pumped a mixture of gases through the material to test its retention of specific gases. The mix contained oxygen, carbon dioxide, argon, krypton, xenon and nitrogen. The krypton and xenon were at very low concentrations. They found that while the O2, CO2, N2 and Ar passed freely through the CC3, xenon and krypton were trapped. CC3 trapped twice as much xenon as the best MOF material tested. The CC3 also trapped twenty times as much xenon as krypton. This property is known as selectivity and it is a very important capability.

        CC3 has been identified as the best noble gas trapper developed so far. The researches do not yet know exactly how CC3 functions when it traps noble gases. When they do understand the way that CC3 functions, it may be possible to fine tune this type of noble gas trapping material to trap different noble gases as desired.

Artist's rendering of the CC3 molecule:

Nuclear Weapons 84 - India - Pakistan - Warheads and Water

         I have blogged about Pakistan and India before in the context of their hostilities and the danger that they might engage in an  exchange of nuclear warheads. They have around a hundred warheads each. It has been estimated that the detonation of only one hundred warheads might be sufficient to trigger a nuclear winter that would end human civilization. They have gone to war three times since India and Pakistan were created in 1949.

         Both India and Pakistan claim the Kashmir region. The name Kashmir used to designate only the valley between the Himalaya and the Pir Panjai mountain ranges. Now the term "Kashmir" refers to a much bigger area. It includes the Indian state of Jammu and Kashmir, the Pakistani territories of Azad Chin and Gilgit-Baltistan and the Chinese controlled Aksai Kashmir and the Trans-Karakoram Tract. Most of the border between the Pakistani and Indian controlled parts of Kashmir is marked by a double twelve foot fence with barbed wire on the top. Much of the rest contains thousands of land mines. There is often automatic weapons fire and mortar fire between the two nations across the border also called "Line of Control" which is really only the cease fire line drawn following hostilities in 1972. This openly contested region could be the trigger for a new war between Pakistan and India.

       Pakistan is dependent on the Indus river for ninety percent of its irrigation water and fifty percent of its employment. The Indus river runs through India before it reaches Pakistan. An agreement over water rights and usage was reached some time ago. Since then, the populations of both countries have exploded and water resources have become more scarce. Now India is building forty five new hydroelectric dams on the Indus in India to supply desperately needed power to India. Pakistan is claiming that India is stealing their water and breaking the agreement. Most nuclear nations have made it official policy to not be the first to launch nuclear missiles in a dispute with another nation. Pakistan has stated that it reserves the right to launch a first nuclear strike against India if India seriously interferes with the flow of water in the Indus River before it reaches Pakistan.

      Pakistan is a  very unstable country. Eight different Islamist militant groups including Al-Qaeda and the Taliban have just joined together in a united jihad coalition against India. There is great international concern that the current government of Pakistan might be overthrown and replaced with a fanatic Islamist government that would have nuclear warheads. India has just elected a new nationalist government which is taking a hard line against Pakistan. Tensions are on the rise  between the two nations. The presence of religious fanaticism in the hostilities between India and Pakistan make the idea of mutually assured destruction preventing nuclear war much less likely.

     As always, when examined closely, issues of nuclear weapons and nuclear power intertwine with economic, social and resource issues. India must increase both energy production and availability of clean water in the near future or face social chaos. Part of India's plan includes building new nuclear reactors, developing a commercial thorium reactor and desalinating water from the ocean (which requires a great deal of energy.) India has sufficient sunshine to power solar energy arrays that could provide the needed electricity the nation and also provide as much water as India requires through desalinization. Hopefully India will be able to meet its energy, water and security needs without the need for nuclear power or nuclear weapons. 

Radioactive Waste 86 - Update on the Recent Accident at the Waste Isolation Pilot Plant 9

         Time for another update on the evolving situation at the Waste Isolation Pilot Plant near Carlsbad, New Mexico. Back in February, something happened in this transuranic geological repository in a salt deposit. Plutonium and americium were detected outside of the plant. When it became possible to examine the big underground room where drums of waste from U.S. nuclear weapons production, it was found that a drum had ruptured and allowed its contents to escape. Further research pointed to a set of waste drums that had been sent to WIPP by the Los Alamos National Laboratory. It was surmised that changes in chemical additives to the barrels resulted in generation of either ammonium nitrates or hydrogen gas which exploded, releasing radioactive materials.

       On the basis of photographs of the breached drum, a small discolored area of the steel shell of the drum indicates that that area reached a temperature of at least six hundred and forty four degrees Fahrenheit. Examination of the damage to gaskets, plastic backfill bags, shrink wrap and slip sheets in the room suggest that the temperature throughout the room must have risen high enough to melt these materials. Some surfaces of the waste drum reached sixteen hundred degrees Fahrenheit. The waste in a large part of the room must have been heated up to four hundred and forty six degrees Fahrenheit.

      Fifty more drums from LANL containing the same nitrate salts as the breached drum may pose a further risk. Temperatures of four hundred and forty six degrees Fahrenheit are sufficient to dry out the nitrate salts in some of these drums. These possible reactions have not been sufficient to show visible evidence but they may result in more breached containers and released radioactive materials. There is a great fear that a chain reaction could occur where exploding drums might trigger even more drums to explode. If sufficient plutonium is released from the drums to pool on the floor and reach a critical mass, a nuclear explosion might occur.

      The operators of the WIPP have been asked if there is any plan for them to go in and removed the dangerous waste drums from LANL. Their response is that there is no such plan at this time because of the danger of radiation exposure to any workers who enter the room with the bad drums.

      The WIPP is the only permanent geological repository for this type of waste. It is becoming more and more likely that the WIPP will not be opened for business any time in the near future. This leaves dangerous drums of waste in room 7 at WIPP, dangerous drums still at LANL and dangerous drums at a temporary waste disposal depot in Texas which is ill prepared to deal with problems caused by chemical reactions from the drums. Going forward, not only is there the usual danger from drums of radioactive waste but also the danger that the drums may explode and spread radioactive materials into the environment. So far, it does not appear that public officials and WIPP operators have found a way to deal with the situation.

WIPP diagram:

Nuclear Reactors 146 - The U.S. General Accounting Office Criticizes the National Nuclear Security Administration

         The security of the U.S. nuclear stockpile and classified nuclear research sites in the United States is overseen by the National Nuclear Security Administration (NNSA). Now a new report by the General Accounting Office accuses the NNSA of increasing risks and reducing security in the past few years to reduce overhead costs.

          In 2009, the NNSA worked to reform security measures with the intent of cutting costs by about fifty three million dollars. The reforms gave independent contractors working for the NNSA "greater authority to make security decisions and accept risks." In addition, the contractors were allowed to self-monitor and self-evaluate the performance. The GAO report charges that these reforms “increased security risks and reduced security performance” at sites secured by the NNSA. The NNSA now admits that some of the changes made after 2009 called for cutting critical protective posts and patrols critical to securing sensitive sites.

          Two years ago there was a major breach in security at Y-12 National Security Complex in Tennessee , one of the sites secured by NNSA. Three people gained access to a protected area adjacent to one of the U.S.'s most important nuclear weapons facilities in the U.S. Although security reforms were enacted by the NNSA because of the 2012 breach, the GAO says that the new reforms have not diminished the risks of further security breaches of this kind. It has been suggested that the breach in security at the Y-12 complex in 2012 was made possible by the reforms started in 2009.

          The GAO report states that the NNSA suffers from a chaotic and dysfunctional security policy. The NNSA security procedures vary from site to site and the NNSA have been unable to “fully [resolve] long-standing security management and oversight problems,” according the GAO report. The GAO report states that the NNSA has put into place "short-lived or ineffective responses to its security problems, on which GAO and others have reported for more than a decade.”

         “The NNSA took a number of actions designed to improve its security performance and oversight but did so without first developing a clear vision and path forward for its security program and an implementation strategy, including milestones and responsibilities for carrying them out,” according the GAO report.

        Since the breach at the Y-12 complex, the NNSA started and then cancelled a security inspection program. They also reorganized their headquarters security twice. What the NNSA has not done is create an NNSA security "road map" as advised by an NNSA security task force in response to the Y-12 complex breach. The GAO continues to pressure the NNSA to create such a road map.

       Considering the havoc that a terrorist attack on a NNSA secured site could wreak, it seems that cutting corners in nuclear security to save fifty three million dollars is a very bad idea.

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