an official journal of: published by:
Editor in Chief: RAFFAELLO COSSU


  • Ana Barrera - Unité Matériaux et Transformations, Université de Lille, France
  • Corinne Binet - Unité Matériaux et Transformations, Université de Lille, France
  • Frédéric Dubois - Unité de Dynamique et Structure des Matériaux Moléculaires, Université du Littoral Côte d'Opale, France
  • Pierre-Alexandre Hébert - Université de Littoral Côte d’Opale, Université du Littoral Côte d'Opale Laboratoire d’Informatique Signal et Image de la Côte d’Opale, France
  • Philippe Supiot - Unité Matériaux et Transformations, Université de Lille, France
  • Corinne Foissac - Unité Matériaux et Transformations, Université de Lille, France
  • Ulrich Maschke - Unité Matériaux et Transformations, Université de Lille, France


Released under CC BY-NC-ND

Copyright: © 2022 CISA Publisher


For several decades, Liquid Crystal Displays (LCDs) have been widely used in televisions, laptops, mobile phones, and other devices. Nowadays, liquid crystals (LCs) represent an important economic value of the recycling system of LCDs. The reuse of these organic molecules could become a profitable basis since it permits to preserve the value of these materials. In this context, the general objective of this work focuses on the recovery of LCs as well as on other valuable materials present in end-of-life LCDs. An orderly, manual LCD dismantling line is put into operation for differentiated recycling of electronic boards, cold cathode lamps that may contain mercury, polymers, metals, and other valuable materials. There is also an extraction line where LCD panels are opened and exposed to an ultrasonically activated organic solvent bath to recover LCs. The resulting solution contains LCs, solvent, organic and inorganic impurities. The LCs mixtures were purified and then characterized mainly by spectroscopic, chromatographic, and thermal techniques. A study of the influence of adding diamond nanoparticles at 0.05, 0.1 and 0.2 wt% to recycled LCs was also performed using dielectric spectroscopy. Dielectric properties of LCs were measured at room temperature, using an impedance analyzer in the frequency range from 0.1 to 106 Hz.


Editorial History

  • Received: 01 Jul 2022
  • Revised: 25 Oct 2022
  • Accepted: 06 Dec 2022
  • Available online: 31 Dec 2022


Barrera, A., Binet, C., Dubois, F., Hébert, P. A., Supiot, P., Foissac, C., & Maschke, U. (2021). Dielectric spectroscopy analysis of liquid crystals recovered from end‐of‐life liquid crystal displays. Molecules, 26(10).
DOI 10.3390/molecules26102873

Centre Européen de la Consommation. (2013). L’obsolescence programmée ou les dérives de la société de consommation.

Cheng, Z., Shi, Q., Wang, Y., Zhao, L., Li, X., Sun, Z., Lu, Y., Liu, N., Su, G., Wang, L., & Sun, H. (2022). Electronic-Waste-Driven Pollution of Liquid Crystal Monomers: Environmental Occurrence and Human Exposure in Recycling Industrial Parks. Environmental Science and Technology, 56(4), 2248–2257.
DOI 10.1021/acs.est.1c04621

Collings, P. J., & Hird, M. (2017). Introduction to liquid crystals: Chemistry and physics. In Introduction to Liquid Crystals: Chemistry and Physics (1 st ed.). Taylor & Francis Ltd: London, UK.
DOI 10.1201/9781315272801

D’Adamo, I., Ferella, F., & Rosa, P. (2019). Wasted liquid crystal displays as a source of value for e-waste treatment centers: a techno-economic analysis. Current Opinion in Green and Sustainable Chemistry, 19, 37–44.
DOI 10.1016/j.cogsc.2019.05.002

de la Fuente, R., & Dunmur, D. (2014). Dielectric properties of liquid crystals. In J. W. Goodby, C. Tschierske, P. Raynes, H. Gleeson, T. Kato, & P. J. Collings (Eds.), Handbook of Liquid Crystals (2 nd ed, pp. 1–10). Wiley‐VCH Verlag GmbH & Co. KGaA.: Weinheim, Germany.
DOI 10.1051/anphys/197803030197

EIT RawMaterials. (2020). DISPLAY: Upscale of material recovery from display applications and Printed Circuit Boards.

European Commission. (2020). Critical raw materials for the EU.

Fontana, D., Forte, F., Pietrantonio, M., & Pucciarmati, S. (2020). Recent developments on recycling end-of-life flat panel displays: A comprehensive review focused on indium. Critical Reviews in Environmental Science and Technology, 51(5), 429–456.
DOI 10.1080/10643389.2020.1729073

Forti, V., Baldé, C. P., Kuehr, R., & Bel, G. (2020). The Global E-waste Monitor 2020: Quantities, flows and the circular economy potential. United Nations University (UNU)/United Nations Institute for Training and Research (UNITAR)

Garbovskiy, Y. (2016). Switching between purification and contamination regimes governed by the ionic purity of nanoparticles dispersed in liquid crystals. Applied Physics Letters, 108(12), 3–8.
DOI 10.1063/1.4944779

Garbovskiy, Y., & Glushchenko, I. (2015). Nano-objects and ions in liquid crystals: Ion trapping effect and related phenomena. Crystals, 5(4), 501–533.
DOI 10.3390/cryst5040501

Goodship, V., Stevels, A., & Huisman, J. (2019). Waste electrical and electronic equipment (WEEE) Handbook (2nd ed.). Woodhead Publishing, Cambridge, UK.
DOI 10.1016/C2016-0-03853-6

ITRI. (2018). LCD Waste Recycling System-Circular Economy-Sustainable Environment-Innovations & Applications-Industrial Technology Research Institute.

Jonscher, A. K. (1977). The “universal” dielectric response. Nature, 267(June), 673–679.

Kelly, S. M., & O’Neill, M. (2001). Liquid crystals for electro-optic applications. In Hari Singh Nalwa (Ed.), Handbook of Advanced Electronic and Photonic Materials and Devices (1 st, Vol. 7, pp. 1–66). Stanford Scientific Corporation: Los Angeles, California, USA

Maschke, U., Moundoungou, I., & Fossi-Tabieguia, G. J. (2015). Method for extracting the liquid crystals contained in an element that comprises a first support and a second support - associated device, FR3017808 (A1), EP3111276 (A1), WO2015128582 (A1): 2017-01-04.

Merck. (1988, 1997 and 2002). Licristal, Liquid crystal mixtures for electro-optic displays

Osipov, M. A., & Gorkunov, M. V. (2016). Nematic liquid crystals doped with nanoparticles: Phase behavior and dielectric properties. In P. F. Jan & G. Scalia (Eds.), Liquid Crystals with Nano and Microparticles. Series in Soft Condensed Matter. (1 st. ed., Vol. 1, pp. 135–175). World Scientific Publishing Company, Singapore.

Oswald, P., & Pieranski, P. (2005). Nematic and Cholesteric Liquid Crystals. In The Liquid Crystals Book Series (1 st ed.). CRC Press Taylor & Francis Group: Boca Raton, FL, USA.
DOI 10.1201/9780203023013

Platform for accelerating the circular economy (PACE). (2019). A New Circular Vision for Electronics Time for a Global Reboot. In World Economic Forum (Issue January).

ReVolv. (2021). ReVolv – Automated Recycling Technologies, LCD recycling, flat screen recycling.

Shen, M., Feng, Z., Liang, X., Chen, H., Zhu, C., Du, B., Li, Q., & Zeng, L. (2022). Release and Gas-Particle Partitioning Behavior of Liquid Crystal Monomers during the Dismantling of Waste Liquid Crystal Display Panels in E-Waste Recycling Facilities. Environmental Science and Technology, 56(5), 3106–3116.
DOI 10.1021/acs.est.1c07394

Singh, S. (2002). Liquid Crystals Fundamentals. In Springer Handbooks (1st ed). World Scientific Publishing Co. Pte. Ltd.
DOI 10.1007/978-0-387-29185-7_38

Song, Q., Zhang, L., & Xu, Z. (2020). Indium recovery from In-Sn-Cu-Al mixed system of waste liquid crystal display panels via acid leaching and two-step electrodeposition. Journal of Hazardous Materials, 381(August 2019), 120973.
DOI 10.1016/j.jhazmat.2019.120973

Su, H., Ren, K., Li, R., Li, J., Gao, Z., Hu, G., Fu, P., & Su, G. (2022). Suspect Screening of Liquid Crystal Monomers (LCMs) in Sediment Using an Established Database Covering 1173 LCMs. Environmental Science & Technology, 56(12), 8061–8070.
DOI 10.1021/acs.est.2c01130

United Nations News. (2019). Environment and health at increasing risk from growing weight of ‘e-waste.’

Viciosa, M. T., Nunes, A. M., Fernandes, A., Almeida, P. L., Godinho, M. H., & Dionísio, M. D. (2002). Dielectric studies of the nematic mixture E7 on a hdroxypropylcellulose substrate. Liquid Crystals, 29(3), 429–441.
DOI 10.1080/02678290110113478

Yang, D. K., & Wu, S. T. (2014). Fundamentals of Liquid Crystal Devices. In Display Technology (1st ed). John Wiley & Sons Ltd, West Sussex, UK.
DOI 10.1002/9781118751992

Zhu, M., Shen, M., Liang, X., Chen, H., Zhu, C., Du, B., Luo, D., Lan, S., Feng, Z., & Zeng, L. (2021). Identification of Environmental Liquid-Crystal Monomers: A Class of New Persistent Organic Pollutants - Fluorinated Biphenyls and Analogues - Emitted from E-Waste Dismantling. Environmental Science and Technology, 55(9), 5984–5992.
DOI 10.1021/acs.est.1c00112