A Study of Direct NH4VO3 Crystallization from Dilute V Solutions and the Effect of Impurities (Fe, Mn) on Crystallization
Kokko, Maria; Hu, Tao; Lassi, Ulla; Pesonen, Janne (2025-02-01)
Springer
01.02.2025
Kokko, M., Hu, T., Lassi, U. et al. A Study of Direct NH4VO3 Crystallization from Dilute V Solutions and the Effect of Impurities (Fe, Mn) on Crystallization. Waste Biomass Valor (2025). https://doi.org/10.1007/s12649-025-02943-8
https://creativecommons.org/licenses/by/4.0/
© The Author(s) 2025. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
https://creativecommons.org/licenses/by/4.0/
© The Author(s) 2025. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
https://creativecommons.org/licenses/by/4.0/
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:oulu-202503172048
https://urn.fi/URN:NBN:fi:oulu-202503172048
Tiivistelmä
Abstract
Industrial side streams, such as steel slag, can contain significant amounts of vanadium (V), and its recovery is important for their beneficial use. This study presents a simple approach for recovery of NH4VO3 by direct crystallization from (NH4)2CO3 matrix without significant reagent additions and a V separation stage. This study investigated several factors (seed crystals, ultrasonic pretreatment, pH, vanadium concentration [V], Fe and Mn impurities) affecting direct NH4VO3 crystallization from dilute V-containing ([V] 1.2–2.4 g/L) synthetic solutions. Besides [V], pH had a significant effect on crystallization, especially in the presence of a main impurity Fe. Fe precipitated rapidly with an amorphous structure during pH adjustment. At sufficiently low pH (< 6.8), NH4VO3 crystallized slowly after Fe-containing precipitate formation. The total V recovery (R%) reached 81% but due to co-precipitation of V and Fe, V losses (2–35%) varied depending on the variation in Fe concentration. To minimize V loss, washing the Fe-containing precipitate with an alkaline solution was carried out with promising results (V R% 16–80%). The presence of Mn increased V R% despite almost complete co-precipitation with NH4VO3. The utilization of seed crystals accelerated the crystallization, but the effect of a three-minute ultrasonic pretreatment had an insignificant effect. The method was applied to authentic leachates ([V] 1.6 g/L) which showed comparable results (V R% 81%). Based on SEM-EDS, NH4VO3 crystals contained only marginally Si. This study demonstrates the significant applicability of direct NH4VO3 crystallization for dilute V solutions and offers a functional method from an industrial perspective.
Industrial side streams, such as steel slag, can contain significant amounts of vanadium (V), and its recovery is important for their beneficial use. This study presents a simple approach for recovery of NH4VO3 by direct crystallization from (NH4)2CO3 matrix without significant reagent additions and a V separation stage. This study investigated several factors (seed crystals, ultrasonic pretreatment, pH, vanadium concentration [V], Fe and Mn impurities) affecting direct NH4VO3 crystallization from dilute V-containing ([V] 1.2–2.4 g/L) synthetic solutions. Besides [V], pH had a significant effect on crystallization, especially in the presence of a main impurity Fe. Fe precipitated rapidly with an amorphous structure during pH adjustment. At sufficiently low pH (< 6.8), NH4VO3 crystallized slowly after Fe-containing precipitate formation. The total V recovery (R%) reached 81% but due to co-precipitation of V and Fe, V losses (2–35%) varied depending on the variation in Fe concentration. To minimize V loss, washing the Fe-containing precipitate with an alkaline solution was carried out with promising results (V R% 16–80%). The presence of Mn increased V R% despite almost complete co-precipitation with NH4VO3. The utilization of seed crystals accelerated the crystallization, but the effect of a three-minute ultrasonic pretreatment had an insignificant effect. The method was applied to authentic leachates ([V] 1.6 g/L) which showed comparable results (V R% 81%). Based on SEM-EDS, NH4VO3 crystals contained only marginally Si. This study demonstrates the significant applicability of direct NH4VO3 crystallization for dilute V solutions and offers a functional method from an industrial perspective.
Kokoelmat
- Avoin saatavuus [38865]
Ellei muuten mainita, aineiston lisenssi on https://creativecommons.org/licenses/by/4.0/