University of Houston researchers have molecular crystals It has been developed that can capture radioactive iodine, which is a by-product of nuclear waste. The crystals are reusable, cost-effective, and can also be used to capture carbon dioxide.
- One of the biggest points of contention over nuclear power is the disposal of nuclear waste.
- A group of researchers used molecular crystals to capture iodine, a major by-product of nuclear fission.
- Crystals can also be used to fix carbon.
Facing the challenges of nuclear waste
Nuclear waste, which is a by-product of nuclear reactors, is classified into low, medium and high level waste, the latter containing most of the radioactivity. Although only a small part of the total waste generated, the management of high-level waste, especially spent fuel, has been a point of contention for many years.
Current methods involve storing spent nuclear fuel in wet or dry storage facilities prior to recycling or disposal. Recycling is a viable option, as about 97 percent of the materials, including uranium and plutonium, can be reused as fuel in certain reactors. Countries like France, Japan, Germany, Belgium, and Russia have used plutonium recycling to generate electricity and reduce the radioactive footprint of their waste.
A pioneering solution to a pervasive problem
So the problem of nuclear waste disposal has always been a great challenge. Existing methods are not only very expensive, but also take up space. Perhaps the Houston researchers cracked the code with a promising solution — molecular crystals based on cyclotetrabenzylhydrazones. These versatile crystals are able to capture radioactive iodine, one of the most common fission products — fission is the process of extracting energy from uranium atoms — in nuclear waste.
This groundbreaking discovery, originally made in 2015 by the same team, has the potential to redefine the way we manage and dispose of nuclear waste. The innovative technology behind these molecular crystals exhibits remarkable iodine adsorption capacity comparable to that of porous MOFs and covalent organic frameworks, materials previously considered the leading solutions for iodine scavenging.
Multiple application options
The applications of these crystals are not limited to nuclear waste management. They also have the potential to capture carbon dioxide, which contributes to global efforts for a cleaner, more sustainable world. In addition, the structure of these crystals is very similar to the materials used in lithium-ion batteries, indicating potential energy-related applications.
The process of producing these crystals is another feather in their cap. They can be manufactured cheaply and on a large scale using commercially available chemicals, with potentially lower cost in an industrial setting. Known as an “octopus” because of its ringed structure, the crystals can be produced in an academic lab at a cost of about $1 per gram.
Step towards a net zero future
The development of these molecular crystals is not only an important step towards a revolution in nuclear waste management, but also a step towards a cleaner and more sustainable world. While the practical applications of these crystals have yet to be explored, the researchers are excited about the possibilities they offer.
Meanwhile, fast breeder reactors (FBRs), another potential solution to the nuclear waste problem, are being considered again in Europe. Recent advances in FBR technology, such as improved designs and heat treatment technologies, offer improved safety features, better fuel efficiency, and reduced waste. However, discussions continue about their role in a greener future, and investment in FBR development and research is seen as critical.
