Bài viết trình bày phương pháp thủy luyện kim được sử dụng để thu hồi kim loại đất hiếm từ các nam châm ổ cứng để tạo ra ôxít kim loại đất hiếm - sản phẩm có độ tinh khiết cao. Từ đó chế tạo chất ức chế ăn mòn cho hợp kim nhôm làm việc trong môi trường xâm thực mạnh như NaCl. | Transport and Communications Science Journal Vol 72 Issue 2 02 2021 204-214 Transport and Communications Science Journal RECOVERY RARE EARTH COMPOUNDS FROM NdFeB MAGNET OF WASTE HDDs AND EXPLORATION THE CORROSION INHIBITION ABITITY FOR ALUMINIUM ALLOY Bui Thi Thanh Huyen1 Pham Khanh Huy2 Ha Duy Dung3 Vu Thi Xuan4 1 National University of Civil Engineering No. 55 Giai Phong Street Hanoi Vietnam 2 Hanoi University of Mining and Geology No. 18 Pho Vien Street Hanoi Vietnam 3 4 University of Transport and Communications No 3 Cau Giay Street Hanoi Vietnam ARTICLE INFO TYPE Research Article Received 15 12 2020 Revised 20 1 2021 Accepted 26 1 2021 Published online 15 2 2021 https Corresponding author Email vuthixuan@ Abstract. The recovery of rare earth compounds from the magnet of waste HDDs and then fabricating a rare earth salt mixture used as an environmentally friendly corrosion inhibitor for metals is a prospective research direction. It has great significance in environmental protection and sustainable development. In this study permanent magnets are collected from some kinds of waste HDDs in Vietnamese market. Hydrometallurgical method is used to recover mixtures of rare earth oxides from permanent magnets. By analyzing EDX ICP-MS and XRD the mixture of rare earth metal oxide product obtained with high purity. The Nd content accounts for over 80 of the rare earth elements weight. Since then the mixture of rare earth chloride salts was fabricated and initially explored the corrosion inhibition ability of the rare earth salt mixture for the aluminum alloys in the strong aggressive environments like NaCl. The mixture of fabricated rare earth chloride salts exhibits an efficient inhibitor for corrosion process of aluminum alloy in NaCl. The inhibition efficiency is stable on time and reach over 92 after about 168 1344 hours immersion by the mass loss method. Keywords Electronic waste rare earth magnets FeNdB corrosion .
