کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4989539 1456929 2018 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
An environmentally friendly electro-oxidative approach to recover valuable elements from NdFeB magnet waste
ترجمه فارسی عنوان
یک رویکرد الکترو اکسیداتیو سازگار با محیط زیست برای بازیابی عناصر ارزشمند از زباله آهنربا NdFeB
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی تصفیه و جداسازی
چکیده انگلیسی


- An electro-oxidative process to recover REEs from NdFeB magnet waste is proposed.
- >95% REEs are recovered as mixed rare-earth oxides with ≥99% purity.
- Valuable FeCl3 by product was obtained that can be used in water treatment industry.
- Speciation of iron is shown to be a critical parameter to recycle NdFeB magnets.

In this manuscript, we demonstrate a room temperature electrochemical process for efficiently recycling NdFeB magnet waste. First, the magnet waste was completely leached with HCl and then, in-situ electrochemical oxidation was performed to selectively oxidize Fe(II) in the leachate to Fe(III). Finally, oxalic acid was added directly to the electro-oxidized leachate which selectively precipitated more than 98% of rare earth elements as rare-earth oxalates. The calcination of rare-earth oxalates produced mixed rare-earth oxides of 99.2% purity and a marketable Fe(III) solution as by-product. The electro-oxidized leachate was also subjected to an alternative neutralization route in which ammonium hydroxide was added to remove iron as ferric hydroxide. The iron free leachate with rare earth elements and cobalt was then subjected to oxalic acid precipitation treatment, which finally produced rare-earth oxides of 99.7% purity. Furthermore, a cobalt-rich solution was obtained in the end and electrowinning studies performed on the solution showed the feasibility of recovering pure metallic cobalt.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Separation and Purification Technology - Volume 191, 31 January 2018, Pages 384-391
نویسندگان
, , , ,