journal article·2025-09-12Open access

Inline Monitoring of Lithium Brines with Low-Field NMR

Eric Schmid, Rahel Lerner, Thomas Rudszuck, Hermann Nirschl, Gisela Guthausen

Applied Sciences· Volume 15· Issue 18

Abstract

The importance of and demand for lithium are high and are expected to further increase. Therefore, efficient lithium exploitation processes are essential, for example, Li extraction from brines. Powerful analytical methods are needed, especially with an inline capability. Nuclear Magnetic Resonance is a widely used analytical tool with extensive possibilities. Low-field NMR is particularly suitable for inline quality control thanks to its customizable applications. This study investigates the possibilities of measuring the lithium content in aqueous solutions and brines using 1H and 7Li NMR based on transverse relaxation measurements, using two different low-field NMR instruments. Both static and measurements under flow are presented. The influence of other parameters, such as sample temperature and sodium content of the brine, has also been investigated. The results demonstrate the proof of concept of quantifying lithium content by low-field NMR and provide detailed insights, whilst showing the prerequisites for future industrial applications for inline quality control in lithium extraction processes.
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Research context

OpenAlex topics: NMR spectroscopy and applications · Advanced MRI Techniques and Applications · Advanced NMR Techniques and Applications

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Institute of Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany

Vulcan Energie Ressourcen GmbH, 76227 Karlsruhe, Germany

Chair of Water Chemistry and Water Technology, Engler-Bunte-Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany

References (30)

Show source-provided references
1. Steiger, K., Hilgers, C., and Kolb, J. (2022). Lithiumbedarf Für Die Batteriezellen-Produktion in Deutschland Und Europa Im Jahr 2030, KIT.
2. A review of in-line and on-line measurement techniques to monitor industrial mixing processes10.1016/j.cherd.2019.10.045 ↗
3. NMR studies of structure and function of biological macromolecules10.1023/B:BIRE.0000007689.27614.7c ↗
4. Qualification of Automated Low-Field NMR Relaxometry for Quality Control of Polymers in a Production Setting10.1016/j.polymertesting.2007.07.005 ↗
5. Flexible automation with compact NMR spectroscopy for continuous production of pharmaceuticals10.1007/s00216-019-01752-y ↗
6. Low-field permanent magnets for industrial process and quality control10.1016/j.pnmrs.2013.09.001 ↗
7. Recent developments in the food quality detected by non-invasive nuclear magnetic resonance technology10.1080/10408398.2018.1441124 ↗
8. Lithium Mobility in Graphite Anodes at Different States of Charge as Observed by NMR10.1021/acs.jpcc.4c08394 ↗
9. The first in situ 7Li NMR study of the reversible lithium insertion mechanism in disorganised carbons10.1016/j.jpcs.2003.10.022 ↗
10. 7Li - NMR of Well-Graphitized Vapor-Grown Carbon Fibers and Natural Graphite Negative Electrodes of Rechargeable Lithium-Ion Batteries10.1149/1.1392009 ↗
11. Chemical analysis by ultrahigh-resolution nuclear magnetic resonance in the Earths magnetic field10.1038/nphys211 ↗
12. Fukushima, E., and Roeder, S.B.W. (1981). Experimental Pulse NMR, A Nuts and Bolts Approach, Addison-Wesley Publishing Company Inc.
13. Abragam, A. (1961). Principles of Nuclear Magnetism, Oxford University Press.10.1063/1.3057238 ↗
14. Blümich, B., Blümich, P. (2005). Essential NMR, Springer Nature.
15. Schmid, E., Rondeau, S., Rudszuck, T., Nirschl, H., and Guthausen, G. (2023). Inline NMR via a Dedicated V-Shaped Sensor. Sensors, 23.10.3390/s23052388 ↗
16. Schmid, E., Pertzel, T.O., Nirschl, H., and Guthausen, G. (2024). Characterization of Flow with a V-Shaped NMR Sensor. Sensors, 24.10.3390/s24196163 ↗
17. Online Rheo-TD NMR for analysing batch polymerisation processes10.1016/j.micromeso.2013.03.001 ↗
18. In-line non-contact check weighing (NCCW) with nuclear magnetic resonance (NMR) presents new opportunities and challenges in process control
19. Why is Inline NMR Rarely Used as Industrial Sensor? Challenges and Opportunities10.1002/ceat.201300380 ↗
20. NMR flow tube for online NMR reaction monitoring10.1021/ac502300q ↗
21. Flow techniques in NMR spectroscopy10.1016/S0066-4103(07)62001-8 ↗
22. Dedicated NMR sensor to analyze relaxation and diffusion in liquids and its application to characterize lubricants10.1002/mrc.5155 ↗
23. Effects of Diffusion on Free Precession in Nuclear Magnetic Resonance Experiments10.1103/PhysRev.94.630 ↗
24. Modified spin-echo method for measuring nuclear relaxation times10.1063/1.1716296 ↗
25. Towards Online-Rheo-TD-NMR in Bypass Lines for Analysing of Batch Polymerization Processes10.1002/cite.201100080 ↗
26. Schmid, E., Kontschak, L., Nirschl, H., and Guthausen, G. (2024). NMR in Battery Anode Slurries with a V-Shaped Sensor. Sensors, 24.10.3390/s24113353 ↗
27. Spin dynamics of Carr–Purcell–Meiboom–Gill-like sequences in grossly inhomogeneous B0 and B1 fields and application to NMR well logging10.1006/jmre.1999.1967 ↗
28. Callaghan, P.T. (1991). Principles of Nuclear Magnetic Resonance Microscopy, Oxford University Press.10.1093/oso/9780198539445.001.0001 ↗
29. Quantitative NMR Imaging of Flow10.1002/cmr.1820050402 ↗
30. Inflow effects on functional MRI10.1016/j.neuroimage.2011.09.088 ↗