Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

From the Ocean into the Reactor

19.11.2013
New sorbents efficiently extract uranium from seawater

Uranium mining for the nuclear industry causes immense environmental damage, which becomes more severe as reserves are depleted.



The isolation of uranium from seawater would be a much more environmentally friendly alternative. In the journal Angewandte Chemie, American researchers have now introduced a process by which they can produce tailored, highly effective adsorption agents to do this job.

Because the concentration of uranyl ions in seawater is very low, adsorption agents used for this process must be particularly efficient. By carefully controlling the surface and pore structures, a team from Oak Ridge National Laboratory and the University of Tennessee has now been able to significantly increase both the rate and capacity of adsorption of a new polymer adsorbent.

Their success stems from a special polymerization technique. Sheng Dai’s team begins by producing a porous polymer framework based on the monomer vinylbenzyl chloride (VBC) with divinylbenzene (DVB) as a cross-linking agent. It is possible to vary the surface properties and pore volume of the product by changing the ratio of VBC to DVB.

The interiors of the resulting frameworks contain many accessible chloride species that then serve as starting points for the next polymerization step, which is known as atom-transfer radical polymerization (ATRP).

This reaction allows the researchers to grow polyacrylonitrile chains within the framework. The advantage of ATRP is that the length of the chains is highly controllable and uniform. In the final step, the polyacrylonitrile is converted to polyamidoxime because amidoxime groups bind well to uranyl ions.

Tests with simulated seawater resulted in distinctly higher and significantly faster uranium adsorption than with conventional, polyethylene-based adsorbents. Experiments showed that the adsorption capacity of the new adsorbent is strongly dependent on the density of amidoxime groups—a parameter that can be tailored by means of the pore size and the number of accessible chloride species in the original nanoporous framework.

“These frameworks are the first example of ATRP initiators in which the initiator species is located within the nanoporous support network,” reports Dai. “This new process puts materials with tailored adsorption and surface properties within reach. The method can be used to produce a wide variety of polymer nanocomposites for applications including the removal of heavy-metal ions from solutions or novel catalysts.”

About the Author
Dr. Sheng Dai is currently a Group Leader of the Nanomaterials Chemistry Group at Oak Ridge National Laboratory (ORNL) and Professor of Chemistry at the University of Tennessee, Knoxville. He had made a number of important contributions to the fields of mesoporous materials and ionic liquids. Because of his outstanding research achievements, he was named a UT-Battelle Corporate Fellow in 2011, the highest designation a researcher can receive at ORNL.

Author: Sheng Dai, Oak Ridge National Laboratory (USA), http://web.ornl.gov/sci/csd/Research_areas/NC_staff.htm

Title: Seawater Uranium Sorbents: Preparation from a Mesoporous Copolymer Initiator by Atom-Transfer Radical Polymerization

Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201307825

Sheng Dai | Angewandte Chemie
Further information:
http://pressroom.angewandte.org.

Further reports about: Angewandte Chemie CHEMISTRY Pacific Ocean ionic liquid oxime group uranium

More articles from Life Sciences:

nachricht Gasoline from a nanoreactor
01.04.2015 | Paul Scherrer Institut (PSI)

nachricht Lizard activity levels can help scientists predict environmental change
01.04.2015 | University of Missouri-Columbia

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Lizard activity levels can help scientists predict environmental change

Research study provides new tools to assess warming temperatures

Spring is here and ectotherms, or animals dependent on external sources to raise their body temperature, are becoming more active. Recent studies have shown...

Im Focus: Hannover Messe 2015: Saving energy with smart façades

Glass-fronted office buildings are some of the biggest energy consumers, and regulating their temperature is a big job. Now a façade element developed by Fraunhofer researchers and designers for glass fronts is to reduce energy consumption by harnessing solar thermal energy. A demonstrator version will be on display at Hannover Messe.

In Germany, buildings account for almost 40 percent of all energy usage. Heating, cooling and ventilating homes, offices and public spaces is expensive – and...

Im Focus: Nonoxide ceramics open up new perspectives for the chemical and plant engineering

Outstanding chemical, thermal and tribological properties predestine silicon carbide for the production of ceramic components of high volume. A novel method now overcomes the procedural and technical limitations of conventional design methods for the production of components with large differences in wall thickness and demanding undercuts.

Extremely hard as diamond, shrinking-free manufacturing, resistance to chemicals, wear and temperatures up to 1300 °C: Silicon carbide (SiSiC) bundles all...

Im Focus: Experiment Provides the Best Look Yet at 'Warm Dense Matter' at Cores of Giant Planets

In an experiment at the Department of Energy's SLAC National Accelerator Laboratory, scientists precisely measured the temperature and structure of aluminum as...

Im Focus: Energy-autonomous and wireless monitoring protects marine gearboxes

The IPH presents a solution at HANNOVER MESSE 2015 to make ship traffic more reliable while decreasing the maintenance costs at the same time. In cooperation with project partners, the research institute from Hannover, Germany, has developed a sensor system which continuously monitors the condition of the marine gearbox, thus preventing breakdowns. Special feature: the monitoring system works wirelessly and energy-autonomously. The required electrical power is generated where it is needed – directly at the sensor.

As well as cars need to be certified regularly (in Germany by the TÜV – Technical Inspection Association), ships need to be inspected – if the powertrain stops...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

World Conference On Regenerative Medicine 2015: Registration And Abstract Submission Now Open

25.03.2015 | Event News

University presidents from all over the world meet in Hamburg

19.03.2015 | Event News

10. CeBiTec Symposium zum Big Data-Problem

17.03.2015 | Event News

 
Latest News

Gasoline from a nanoreactor

01.04.2015 | Life Sciences

Saving costs with antifouling coatings

01.04.2015 | Process Engineering

Diversity prevents resistance

01.04.2015 | Agricultural and Forestry Science

VideoLinks
B2B-VideoLinks
More VideoLinks >>>