Pulling uranium from seawater

A new material in development may make fueling nuclear reactors with uranium harvested from the ocean more feasible.

09/19/2012


ISS SourceA new material in development may make fueling nuclear reactors with uranium harvested from the ocean more feasible.

By combining Department of Energy’s Oak Ridge National Laboratory’s (ORNL) high-capacity reusable adsorbents and a Florida company’s high-surface-area polyethylene fibers creates a material that can rapidly, selectively and economically extract valuable and precious dissolved metals from water.

The material, HiCap, outperforms today’s best adsorbents, which perform surface retention of solid or gas molecules, atoms or ions. HiCap also effectively removes toxic metals from water, according to results verified by researchers at Pacific Northwest National Laboratory.

“We have shown that our adsorbents can extract five to seven times more uranium at uptake rates seven times faster than the world’s best adsorbents,” said Chris Janke, one of the inventors and a member of ORNL’s Materials Science and Technology Division.

HiCap effectively narrows the fiscal gap between what exists today and what they need to economically extract some of the ocean’s estimated 4.5 billion tons of uranium. Although dissolved uranium exists in concentrations of just 3.2 parts per billion, the sheer volume means there would be enough to fuel the world’s nuclear reactors for centuries.

The goal of extracting uranium from the oceans began with research and development projects in the 1960s, with Japan conducting the majority of the work. Other countries pursuing this goal include Russia, China, Germany, Great Britain, India, South Korea, Turkey and the United States. Researchers developed adsorbent materials, but none has emerged as being economically viable.

What sets the ORNL material apart is the adsorbents are made from small diameter, round or non-round fibers with high surface areas and excellent mechanical properties. By tailoring the diameter and shape of the fibers, researchers can significantly increase surface area and adsorption capacity. This and ORNL’s patent pending technology to manufacture the adsorbent fibers results in a material able to selectively recover metals more quickly and with increased adsorption capacity, thereby dramatically increasing efficiency.

“Our HiCap adsorbents are made by subjecting high-surface area polyethylene fibers to ionizing radiation, then reacting these pre-irradiated fibers with chemical compounds that have a high affinity for selected metals,” Janke said.

After the processing, scientists can place HiCap adsorbents in water containing the targeted material, which ends up quickly and preferentially trapped. Scientists then remove the adsorbents from the water and the metals end up extracted using a simple acid elution method. They can then regenerate and reuse the adsorbent after conditioning it with potassium hydroxide.

In a direct comparison to the current state-of-the-art adsorbent, HiCap provides significantly higher uranium adsorption capacity, faster uptake and higher selectivity, according to test results. Specifically, HiCap’s adsorption capacity is seven times higher (146 vs. 22 grams of uranium per kilogram of adsorbent) in spiked solutions containing 6 parts per million of uranium at 20 degrees Celsius. In seawater, HiCap’s adsorption capacity of 3.94 grams of uranium per kilogram of adsorbent was more than five times higher than the world’s best at 0.74 grams of uranium per kilogram of adsorbent. The numbers for selectivity showed HiCap to be seven times higher.

“These results clearly demonstrate that higher surface area fibers translate to higher capacity,” Janke said.

ORNL researchers conducted field tests of the material at the Marine Sciences Laboratory of Pacific Northwest National Laboratory in Sequim, WA, and at the Rosenstiel School of Marine & Atmospheric Science and Broad Key Island in collaboration with the University of Miami.



Top Plant
The Top Plant program honors outstanding manufacturing facilities in North America.
Product of the Year
The Product of the Year program recognizes products newly released in the manufacturing industries.
System Integrator of the Year
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
October 2018
Tools vs. sensors, functional safety, compressor rental, an operational network of maintenance and safety
September 2018
2018 Engineering Leaders under 40, Women in Engineering, Six ways to reduce waste in manufacturing, and Four robot implementation challenges.
July/Aug
GAMS preview, 2018 Mid-Year Report, EAM and Safety
October 2018
2018 Product of the Year; Subsurface data methodologies; Digital twins; Well lifecycle data
August 2018
SCADA standardization, capital expenditures, data-driven drilling and execution
June 2018
Machine learning, produced water benefits, programming cavity pumps
Spring 2018
Burners for heat-treating furnaces, CHP, dryers, gas humidification, and more
October 2018
Complex upgrades for system integrators; Process control safety and compliance
September 2018
Effective process analytics; Four reasons why LTE networks are not IIoT ready

Annual Salary Survey

After two years of economic concerns, manufacturing leaders once again have homed in on the single biggest issue facing their operations:

It's the workers—or more specifically, the lack of workers.

The 2017 Plant Engineering Salary Survey looks at not just what plant managers make, but what they think. As they look across their plants today, plant managers say they don’t have the operational depth to take on the new technologies and new challenges of global manufacturing.

Read more: 2017 Salary Survey

The Maintenance and Reliability Coach's blog
Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
One Voice for Manufacturing
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Maintenance and Reliability Professionals Blog
The Society for Maintenance and Reliability Professionals an organization devoted...
Machine Safety
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
Research Analyst Blog
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Marshall on Maintenance
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
Lachance on CMMS
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.
Material Handling
This digital report explains how everything from conveyors and robots to automatic picking systems and digital orders have evolved to keep pace with the speed of change in the supply chain.
Electrical Safety Update
This digital report explains how plant engineers need to take greater care when it comes to electrical safety incidents on the plant floor.
IIoT: Machines, Equipment, & Asset Management
Articles in this digital report highlight technologies that enable Industrial Internet of Things, IIoT-related products and strategies.
Randy Steele
Maintenance Manager; California Oils Corp.
Matthew J. Woo, PE, RCDD, LEED AP BD+C
Associate, Electrical Engineering; Wood Harbinger
Randy Oliver
Control Systems Engineer; Robert Bosch Corp.
Data Centers: Impacts of Climate and Cooling Technology
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
Safety First: Arc Flash 101
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
Critical Power: Hospital Electrical Systems
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
Design of Safe and Reliable Hydraulic Systems for Subsea Applications
This eGuide explains how the operation of hydraulic systems for subsea applications requires the user to consider additional aspects because of the unique conditions that apply to the setting
click me