De’an Pan

Challenges in legislation, recycling system and technical system of waste electrical and electronic equipment in China.

Waste electrical and electronic equipment (WEEE) has been one of the fastest growing waste streams worldwide. Effective and efficient management and treatment of WEEE has become a global problem. As one of the worlds largest electronic products manufacturing and consumption countries, China plays a key role in the material life cycle of electrical and electronic equipment. Over the past 20 years, China has made a great effort to improve WEEE recycling. Centered on the legal, recycling and technical systems, this paper reviews the progresses of WEEE recycling in China. An integrated recycling system is proposed to realize WEEE high recycling rate for future WEEE recycling.

Bonded cylindrical Terfenol-D-epoxy/PZT magnetoelectric composites prepared by the one-step compression molding

Magnetoelectric composites with bonded Terfenol-D-epoxy (TDE) and PZT cylindrical ceramics were prepared by the one-step compression molding at room temperature. The PZT cylindrical ceramics not only provided the piezoelectric phase, but also acted as a mold for TDE. The axial ME voltage coefficient of the cylindrical composites, αE,A, was studied. By contrast, the new structure has a larger ME voltage coefficient compared with the effective planar laminated composites due to the self-bound state. This study decreases the ME composite dimensions, making it a promising candidate for the magnetic field sensor applications.

WITHDRAWN: A critical review of recycling rare-earths from waste phosphor.

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

Edge geometry effects on resonance response of electroplated cylindrical Ni/PZT/Ni magnetoelectric composites

Trilayer Ni/PZT/Ni cylindrical magnetoelectric (ME) composites were prepared by electrodeposition, a process, which creates sub-millimeter raised edges due to current concentration near sharp points. The ME response in both axial and vertical modes was measured with the edges, with only outer edges removed, and with both outer and inner edges removed. The ME voltage coefficient improved at resonance by 40% and 147% without the edges in the vertical and axial modes, respectively. The observed improvements in three different samples were only present at the ME resonance and no changes were detected outside of the ME resonance. Mechanical quality factor at resonance also improved with no effect on the resonant frequency. Experimentally demonstrated minor geometry changes resulted in substantial ME improvement at resonant frequency. This study demonstrates device performance optimization. The observed effects have been attributed to improved vibrations in terms of decreased damping coefficient and enhanced vi...

Recycle Rare Earth from Wastephosphor by a Two‐Step Method

In this paper, a new two acid hydrolysis (TAH) method has been studied for leaching rare earth (RE) from waste rare earth tricolor phosphor powders collected from spent fluorescent lamps and cathode ray tubes. Firstly, red phosphor powders (Y2O3: Eu) were dissolved by hydrochloric acid. Blue phosphor powders (Ba0.9Mg2Al16O27:0.1Eu) and Green phosphor powders (MgAl11O19: Ce, Tb) of the waste powder could not be dissolved by acid, which is named as “residue 1”, Leaching rate of yttrium and europium were 96.767% and 93.686%, respectively. Secondly, the residue 1 was decomposed into the mixture of NaAlO2, MgO, BaCO3 and Rare Earth Oxide (REO) by alkali fusion at 800°C for 2 hours. The mixture was separated into NaAlO2 solution and residue 2 containing REO by water-washing and filtrating. Finally, residue 2 was dissolved by hydrochloric acid. The total RE (TRE) leaching rate was 97.87% and the leaching rates of yttrium, europium, terbium and cerium after two acid hydrolysis were 98.405%, 99.02%, 98.45% and 96.16%, respectively. Ca2+, Mg2+ and Ba2+, were removed by adding Na2SO4. Compared to traditional method, one acid hydrolysis (OAH), TAH method could decrease the consumption of caustic soda, which is only 1/3~1/2, and reduce the burden of later RE extraction, separation and purification.