Prof. Xi CHEN

Education
PhD in Environmental Engineering, Columbia University, U.S.
Staff title
Assistant Professor

Dr. Xi Chen received his Ph.D. in Environmental Engineering from Columbia University in 2020. He completed his M.S. and B.S. trainings at University of Illinois at Urbana-Champaign (2015) and Nankai University (2013), respectively. He joined City University of Hong Kong as an assistant professor in Jan. 2024, and he was a postdoctoral researcher in Chemical Engineering at Stanford University before starting the independent career.

Dr. Chen focused his studies on developing separation technologies for various applications in the water-energy nexus, including 1) evaluating and designing separations for recycling lithium-ion batteries, 2) treatment and management of high-salinity brines, 3) advancing membrane transport theory for water purification, and 4) utilization of low-temperature heat. He is an Early Career Board member of Desalination and Environmental Science and Ecotechnology.

Other Information

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 permeabilityselectivity 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
Staff Image
Xi CHEN
Contact Information
Office: YEUNG-B5437
Phone: +(852)-3442-9971
Fax: +(852)-3442-0688
Email: xche26@cityu.edu.hk
Website: https://www.see-chenlab-xeparation.com/

Time slots for consultation

Research Interests
  • Circularizing battery manufacturing
  • Energy-efficient water purification/desalination
  • Removal of emerging contaminants