Research Interests

At CityU, Chen’s group advances separation technologies with single-species selectivities that increase the sustainability of water treatment processes and resource recovery from wastewater. Our research combines experimental and computational engineering, and aims at applications in 1) circularizing battery manufacturing, 2) energy-efficient water purification/desalination, and 3) removal of emerging contaminants.

Active projects are 1) engineering polymer membrane materials for high-precision extraction of value-added components, 2) advancing membrane transport theory in complex environments, and 3) establishing assessment frameworks to compare different separation technologies used in water treatment and resource recovery.

Positions Available

We are looking for motivated Ph.D. students with a curiosity for science and an appetite for knowledge. Background in Environmental Engineering, Chemical Engineering, Mechanical Engineering, Materials Science & Engineering, or a closely related field is preferred. Prior research experience and industry training are both highly valued.

Interested candidates are encouraged to contact Prof. Chen anytime to discuss research opportunities. Please email Prof. Chen at xche26@cityu.edu.hk, with 1) a CV, 2) undergraduate and graduate transcripts, and 3) journal publications or manuscripts.

City University of Hong Kong is an equal opportunity employer and we are committed to the principle of diversity. We encourage applications from all qualified candidates, especially applicants who will enhance the diversity of our staff.

Selected Publications

1. Machala, M. L.^#; Chen, X.^#; Bunke, S. P.^#; Forbes, G.; Yegizbay, A.; de Chalendar, J.A.; Azevedo, I.; Benson, S.; Tarpeh, W. A. Life cycle comparison of industrial-scale lithium-ion battery recycling and mining supply chains. 10.26434/chemrxiv-2023-qwmb2-v4
2. Chen, X.; Verbeke, R.; Boo, C.; Dickmann, M.; Egger, W.; Ndamage, K.; Vankelecom, I. F. J.; Yip, N. Y. Elucidating the roles of polyamide layer structural properties in the permeability–selectivity tradeoff governing aqueous separations. ACS ES&T Engineering. 2022. doi.org/10.1021/acsestengg.2c00103
3. Chen, X.; Boo, C.; Yip, N. Y. Influence of solute molecular diameter on permeability–selectivity tradeoff of thin-film composite polyamide membranes in aqueous separations. Water Research. 2021, 117311. doi.org/10.1016/j.watres.2021.117311
4. Chen, X.; Boo, C.; Yip, N. Y. Transport and structural properties of osmotic membranes in high-salinity desalination using cascading osmotically mediated reverse osmosis. Desalination. 2020, 479, 114335. doi.org/10.1016/j.desal.2020.114335
5. Chen, X.; Boo, C.; Yip, N. Y. Low-temperature heat utilization with vapor pressure-driven osmosis: Impact of membrane properties on mass and heat transfer. Journal of Membrane Science. 2019, 588, 117-181. doi.org/10.1016/j.memsci.2019.117181
6. Chen, X.; Yip, N. Y. Unlocking high-salinity desalination with cascading osmotically mediated reverse osmosis: Energy and operating pressure analysis. Environmental Science & Technology. 2018, 52 (4), 2242-2250. doi.org/10.1021/acs.est.7b05774
7. Chen, X.^#; Huo, X.^#; Liu, J.; Wang, Y.; Werth, C. J.; Strathmann, T. J. Exploring beyond palladium: Catalytic reduction of aqueous oxyanion pollutants with alternative platinum group metals and new mechanistic implications. Chemical Engineering J 2017, 313, 745-752. doi.org/10.1016/j.cej.2016.12.058