Navigation Links
Filter developed by VTT helps recover 80 percent of gold in mobile phone scrap
Date:4/10/2014

Mobile phone scrap can contain precious metals, such as gold and copper. VTT Technical Research Centre of Finland has developed a biological filter made of mushroom mycelium mats enabling recovery of as much as 80% of the gold in electronic scrap. Extraction of copper from circuit board waste, on the other hand, can be enhanced significantly by flotation the crushed and sieved material.

Although research into the biological methods is active, these are still rarely used in metal recovery chains. In a European "Value from Waste" project, VTT developed both biological and mechanical pre-treatment methods for more efficient recovery of precious metals from electronic waste. Other methods developed by researchers included recovery of gold from dissolved materials by biosorption and extraction, using as few harmful chemicals as possible.

Fungi catch gold and filter out impurities

VTT has developed a method that harnesses biosorbents, such as fungal and algae biomass, for the recovery of precious metals converted to a solution. In VTT tests, more than 80% of the gold in the solution adhered to the biomass, compared with only 1020% of the harmful process chemicals.

The uniqueness of the method lies in the structure of the biomass. Different filament structures can be formed, for example, into biological filters, which makes further industrial processing of precious metals easier.

Gold also separates well in liquid-liquid extraction

The project developed a method with high extraction capacity for gold recovery, using the newest environmentally-friendly extraction reagents. In VTT experiments, it was possible to recover more than 90% of the metal solution dissolved from a circuit board with the help of functional ionic liquid. The method facilitates extraction of desired components from impurities.

Recovering copper from circuit boards by flotation

The new pre-treatment methods developed by VTT allow separation of most plastics and ceramics from waste. In VTT experiments, cell phones were crushed and the particles sieved and separated magnetically and by eddy current into circuit board fraction. Treating once more by crushing, sieving and flotation, resulted in a fraction with high concentration of valuable metals for solution extraction experiments. Flotation raised the copper content of circuit board fraction from 25% to 45%, while gold content increased by a factor of 1.5.

"Value from Waste" project

The growth of cleantech industry, the rise in the world market prices of metals, and concentration of metal production in China have resulted in a situation in which extraction of several metals from waste streams has become advisable even in Finland. Ever stricter recycling and utilisation rates for electronic waste are also pushing the development of recycling technologies. The purpose of the EU project "Value from Waste" was to develop recovery processes on a more sustainable basis, to clean materials of impurities that reduce opportunities for further use, and to increase the amount of recovered materials.

The methods developed in the project included mechanical pre-treatment, solution extraction, use of biological methods, and optimisation of treatment chains. The new treatment methods will enable the metal refining industry to use cleaner electronic waste in larger amounts.

In the two-year "Value from Waste" project of the research consortium AERTO (Associated European Research and Technology Organizations), VTT participated in joint technology R&D with the following six European research institutes: Fraunhofer ICT and Umsicht (Germany), CEA (France), TNO (the Netherlands), SINTEF (Norway), Tecnalia (Spain) and SP (Sweden). The project was co-ordinated by SINTEF from Norway.

Flotation

Flotation is a separation method that separates hydrophobic particles from hydrophilic particles by blowing air into sludge containing both types of particles. Hydrophobic particles are picked up by air bubbles and float to the top of the sludge as froth that can be skimmed off mechanically.

Liquid-liquid extraction

Liquid-liquid extraction is a method that extracts metals at aqueous interface selectively into another organic interface immiscible with water. This method, widely used in industrial processes, enables selective extraction of precious and heavy metals from water. The metal solution concentrated into an organic interface is thus extracted in purer form for further processing.


'/>"/>

Contact: Olli Salmi
olli.salmi@vtt.fi
358-207-225-216
VTT Technical Research Centre of Finland
Source:Eurekalert

Related biology news :

1. Nano-paper filter removes viruses
2. Special air filter blocks small particles called UFPs from getting inside cars
3. Living biofilters could reduce greenhouse gas emissions
4. Solar-powered nanofilters pump in antibiotics to clean contaminated water
5. Medical societies to launch large-scale study on vein filter use
6. Synthetic biofilter wins through to the top Sweet 16 in Boston
7. A brain filter for clear information transmission
8. Innovative solutions for lab-automation developed by Bioprocess Engineers from Dresden
9. Ancient food webs developed modern structure soon after mass extinction
10. The basis of a new bioinsecticide is developed to control a pest of banana plantations
11. Caltech-developed method for delivering HIV-fighting antibodies proven even more promising
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/28/2016)... SAN FRANCISCO and BANGALORE, India ... part of EdgeVerve Systems, a product subsidiary of Infosys (NYSE: ... service provider, today announced a global partnership that ... convenient way to use mobile banking and payment services. ... Mobility is a key innovation area for financial services, but ...
(Date:4/28/2016)... Sweden , April 28, 2016 First ... M (139.9), up 966% compared with the first quarter of 2015 ... profit totaled SEK 589.1 M (loss: 18.8) and the operating margin ... 7.12 (loss: 0.32) Cash flow from operations was SEK ... The 2016 revenue guidance is unchanged, SEK 7,000-8,500 M. ...
(Date:4/26/2016)... LONDON , April 26, 2016 ... EdgeVerve Systems, a product subsidiary of Infosys (NYSE: ... a partnership to integrate the Onegini mobile security ... (Logo: http://photos.prnewswire.com/prnh/20151104/283829LOGO ) The ... enhanced security to access and transact across channels. ...
Breaking Biology News(10 mins):
(Date:4/28/2016)... ... April 28, 2016 , ... As ... recruiting top industry experts, and expanding its LATAM network and logistics capabilities. ... clients to manage their clinical trial projects. , The expansion will provide unmatched ...
(Date:4/27/2016)... ... April 27, 2016 , ... ... screen mobile devices with fingerprint recognition for secure access, voice recognition for hands-free ... few ways consumers are interacting with biometrics technology today. But if they ...
(Date:4/27/2016)... ... 2016 , ... PathSensors, Inc., a leading environmental testing company, ... assist PathSensors in expanding the use of the company‚Äôs CANARY® technology in the ... for the detection of harmful pathogens, including a number of bacteria, viruses, toxins, ...
(Date:4/27/2016)... 27, 2016 ReportsnReports.com adds ... specific focus on US, EU, China ... to the healthcare business intelligence collection of its ... Complete report on the Flow Cytometry market spread ... with 282 tables and figures is now available ...
Breaking Biology Technology: