High-Gradient Magnetic Separation of Compact Fluorescent Lamp Phosphors: Elucidation of the Removal Dynamics in a Rotary Permanent Magnet Separator

In an ongoing effort towards a more sustainable rare-earth element market, there is a high potential for an efficient recycling of rare-earth elements from end-of-life compact fluorescent lamps by physical separation of the individual phosphors. In this study, we investigate the separation of five fluorescent lamp particles by high-gradient magnetic separation in a rotary permanent magnet separator. We thoroughly characterize the phosphors by ICP-MS, laser diffraction analysis, gas displacement pycnometry, surface area analysis, SQUID-VSM, and Time-Resolved Laser-Induced Fluorescence Spectroscopy. We present a fast and reliable quantification method for mixtures of the investigated phosphors, based on a combination of Time-Resolved Laser-Induced Fluorescence Spectroscopy and parallel factor analysis. With this method, we were able to monitor each phosphors’ removal dynamics in the high-gradient magnetic separator and we estimate that the particles’ removal efficiencies are proportional to (d2·χ)1/3. Finally, we have found that the removed phosphors can readily be recovered easily from the separation cell by backwashing with an intermittent air–water flow. This work should contribute to a better understanding of the phosphors’ separability by high-gradient magnetic separation and can simultaneously be considered to be an important preparation for an upscalable separation process with (bio)functionalized superparamagnetic carriers.

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A High-Gradient Magnetic Separation System for Separating Magnetic Nanobeads from Aqueous Solution

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.505.39 ◽

2012 ◽

Vol 505 ◽

pp. 39-43

Author(s):

Xiao Fei Yan ◽

Jian Han Lin ◽

Rong Hui Wang ◽

Mao Hua Wang ◽

Dong An ◽

...

Keyword(s):

Aqueous Solution ◽

Magnetic Separation ◽

Flow Rate ◽

Separation System ◽

Magnetic Separator ◽

High Gradient Magnetic Separation ◽

High Gradient ◽

Separation Time ◽

Electronic Timer ◽

Magnetic Nanobeads

Magnetic separation is an emerging and promising technology in biological sample preparation. In this paper, a high-intensity and high-gradient magnetic separation system was developed to separate magnetic nanobeads from aqueous solution. This system mainly consisted of a magnetic separator, a micropump and an electronic timer. The magnetic separator was designed by placing two columns of permanent magnets in an aluminum holder. Two magnets in each column were laid out in repelling mode and a hole between the two columns was used to accommodate a 1.5 ml tube. Working with the electronic timer, the micropump was employed to remove waste solution at a certain rate after magnetic nanobeads captured onto the sides of the tube wall. The experiments for separation of magnetic nanobeads with diameters of 150 nm and 50 nm using the developed magnetic separation system were conducted to optimize the key parameters of the system including nanobeads concentration, separation time and flow rate. The separation efficiencies of magnetic nanobeads increased as the nanobeads concentration and the separation time increased, whereas decreased when the flow rate was increased. Experimental results proved that the proposed magnetic separation system was able to separate magnetic nanobeads (diameters of 150 nm and 50 nm) with separation efficiencies of 99% and 90% in 30 min and 150 min respectively.

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Purification of Refractories Andalusite of High Quality

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.443.609 ◽

2013 ◽

Vol 443 ◽

pp. 609-612

Author(s):

Jun Xun Jin ◽

Hui Min Gao ◽

Jun Fang Guan ◽

Xiao Fei Feng

Keyword(s):

Magnetic Separation ◽

Isoelectric Point ◽

Refractory Materials ◽

High Quality ◽

Magnetic Separator ◽

High Gradient Magnetic Separation ◽

High Gradient ◽

Petroleum Sulfonate ◽

Developing Trend ◽

Flotation Cell

It is a developing trend for the refractory materials industry that producing refractories using the andalusite ore with minute amounts of titanium. The tests were conducted with an ore sample by a high gradient magnetic separator and a mechanical flotation cell. The isoelectric point of the andalusite ore was found to be pH 5.9. Petroleum sulfonate was found to be an effective collector for andalusite flotation. 52.08% Al2O3 is produced with 52.92% andalusite recovery by grinding, desliming, high gradient magnetic separation and andalusite flotation.

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Application of Super Conducting High Gradient Magnetic Separation Technology on Resource Utilization of Low Grade Iron Ore

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.968.168 ◽

2014 ◽

Vol 968 ◽

pp. 168-172 ◽

Cited By ~ 1

Author(s):

Hai Tao Wen ◽

Su Qin Li ◽

Chang Quan Zhang ◽

Wei Wei

Keyword(s):

Magnetic Separation ◽

Steel Industry ◽

Iron Ore ◽

Environmental Problems ◽

Low Grade ◽

Magnetic Separator ◽

High Gradient Magnetic Separation ◽

High Gradient ◽

Separation Technology ◽

Super Conducting

Nowadays, steel industry develops rapidly. However, lots of iron ore needed by China’s steel industry are imported from abroad. China’s dependence on foreign iron ore exceeds 70%. As a result, not only have large amounts of foreign currencies been spent but also a potential threat has been posed to the economic development of our country. Therefore, it is necessary for China to serve its economic production with lots of low grade iron ore. Since traditional beneficiation methods can cause serious environmental problems, High gradient magnetic separation(HGMS) is discussed in this paper. It can recycle tailings when disposing of low grade iron ore as well as solve the environmental problems caused by tailings and arising during the production process. Besides, high gradient magnetic separator can also raise the processing efficiency of low grade iron core. Therefore, high-gradient magnetic separation can not only increase economic returns but also protect ecological environment. With the maturity of super-conduction high gradient magnetic separation technology, super-conducting high gradient magnetic separation will produce better production effects.

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