Highly selective recovery of rare earth elements from mine wastewater by modifying kaolin with phosphoric acidShow others and affiliations
2023 (English)In: Separation and Purification Technology, ISSN 1383-5866, E-ISSN 1873-3794, Vol. 309, article id 123117Article in journal (Refereed) Published
Abstract [en]
Recovery of rare earth elements (REEs) from mine wastewater is essential for maintaining rare earth reserves and sustainable application of REEs. In the present study, we prepared a phosphoric acid modified kaolin (P-K) adsorbent by a simple mechanochemical process for the selective recovery of REEs from rare earth wastewater. The impacts of phosphoric acid dosage, milling duration, initial pH, temperature, initial ion concentration, and adsorbent dosage on the selective adsorption of REEs were investigated. The findings demonstrate that the adsorption of REEs by P-K follows pseudo-second-order kinetic model and the Langmuir isotherm model, and is dominated by chemical adsorption, with a maximum adsorption capacity of 19.82Â mg/g at 50 â. Additionally, in an original mine wastewater, the recovery rate of REEs can reach more than 90%, whereas the adsorption rates of calcium, magnesium and, ammonia nitrogen (whose concentration is 18 times that of REEs) are nearly zero, indicating that P-K has extremely high selectivity for REEs. Furthermore, the feedstock solution containing 40Â mg/L of REEs may be concentrated to 3510Â mg/L following enrichment treatment, and 99.9% of the REEs are eluted using a low concentration of hydrochloric acid. The findings illustrate that P-K has a wide range of potential applications in the treatment of rare earth industrial effluents.
Place, publisher, year, edition, pages
Elsevier, 2023. Vol. 309, article id 123117
Keywords [en]
Modified kaolin, Rare earth wastewater, Adsorption, Selective recovery
National Category
Earth and Related Environmental Sciences
Research subject
Energy Engineering
Identifiers
URN: urn:nbn:se:ltu:diva-100409DOI: 10.1016/j.seppur.2023.123117ISI: 000978746000001Scopus ID: 2-s2.0-85146019997OAI: oai:DiVA.org:ltu-100409DiVA, id: diva2:1788344
Note
Validerad;2023;Nivå 2;2023-08-16 (marisr);
Funder: Jiangxi Province Key Laboratory of Cleaner Production of Rare Earths (no. E03MYB0302); Research Projects of Ganjiang Innovation Academy, Chinese Academy of Sciences (no. E055ZA01); Self-deployed Projects of Ganjiang Innovation Academy, Chinese Academy of Sciences, and the Key Research Program of the Chinese Academy of Sciences (no. ZDRW- CN-2021-3); China National Key R & D Program (Grant no. 2022YFB3504303)
2023-08-162023-08-162025-02-07Bibliographically approved