Four-step eco-friendly energy efficient recycling of contaminated Nd₂Fe₁₄B sludge and coercivity enhancement by reducing oxygen content.

ABSTRACT: Complete recycling of Nd₂Fe₁₄B sludge by chemical methods has gained significance in recent years, however, it is not easy to recycle highly contaminant sludge and obtain product with good magnetic properties. Herein we report a simple four-step process to recycle the Nd₂Fe₁₄B sludge containing ~ 10% of contaminants. Sludge was leached in H₂SO₄ and selectively co-precipitated in two steps. In the first co-precipitation, Al³⁺ and Cu²⁺ were removed at pH 6. Thereafter, in the second co-precipitation Fe²⁺ and RE³⁺ sulfates were converted to the Fe and RE hydroxides. By annealing at 800 °C RE and Fe hydroxides precipitates were converted to the oxides and residual carbon was oxidized t

SUBMITTER: Haider SK 

PROVIDER: S-EPMC8593190 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature