Electrochemical Probe for Rapid Scrap Metal Sorting

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Palo Alto,
Project Term:
12/12/2013 - 05/31/2016

Critical Need:

Recycling light metals such as aluminum, titanium, and magnesium from scrap is primarily done manually, making it an inefficient and expensive process. Existing automated technologies are unable to distinguish different types of alloys. Innovation in light metal recycling is crucial because light metals can be used to reduce the weight of cars and aircraft, which could significantly reduce both energy use and carbon dioxide (CO2) emissions from transportation. Cost-effective scrap recycling could dramatically reduce the cost of light-weight metals, such as those used for aircraft construction and vehicle light-weighting.

Project Innovation + Advantages:

Palo Alto Research Center (PARC) is developing an advanced diagnostic probe that identifies the composition of light metal scrap for efficient sorting and recycling. Current sorting technologies for light metals are costly and inefficient because they cannot distinguish between different grades of light metals for recycling. Additionally, state-of-the-art electrochemical probes rely on aqueous electrolytes that are not optimally suited for separating light metal scrap. PARC’s probe, however, uses a novel liquid, which enables a chemical reaction with light metals to represent their alloy composition accurately. A probe that is more accurate than existing methods could separate scrap based on alloy quality to obtain low-cost, high-quality aluminum.

Potential Impact:

If successful, PARC’s diagnostic probe would facilitate the recycling of discarded light metal scrap.


Light-weighting vehicles to improve fuel efficiency could reduce U.S. dependence on foreign fossil fuel resources used in the transportation industry.


Recycling metals rather than producing them from primary ores consumes less energy and reduces CO2 emissions associated with light metals manufacturing.


Light metal recycling enables aggressive fuel efficiency standards to be met and saves as much as 1.2B gallons of fuel per year, which would save the U.S. over $4 billion in fuel costs.


ARPA-E Program Director:
Dr. Jason Rugolo
Project Contact:
Dr. Jessy Rivest
Press and General Inquiries Email:
Project Contact Email:


Alcoa, Inc.

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