ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Preparation of chitosan-copper material and its application on propylene-propane adsorption separation

Dongyu Jin, Yuming Tu, Zidong Zhang, Zhiyong Zhou, and Zhongqi Ren

State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, People’s Republic of China

E-mail: zhouzy@mail.buct.edu.cn

Received: 10 August 2023  Accepted: 12 March 2024

Abstract:

Propylene is one of the most important olefins in the industry, and conventional separation of propylene/propane relies on low-temperature distillation, which consumes huge amounts of energy. The adsorption separation technique requires low energy consumption and has developed into an important method for the separation of propylene/propane. In this work, chitosan is used as the carbon source, and Cu(II) is immobilized in the molecule through the coordination of –OH and –NH₂ in chitosan with Cu(II). By freeze-drying and high-temperature calcination, Cu(II) in chitosan was reduced to Cu(I), resulting in a porous carbon material containing Cu(I). The adsorption properties of the materials were tested for propylene and propane at 298 K, 1 bar. The Langmuir–Freundlich model was used to fit the adsorption curves and the IAST theory was combined to calculate the selectivity of propylene/propane. The adsorption capacity of carbon materials for propane/propylene under different preparation conditions showed that the best adsorption separation performance for propylene/propane was obtained when the freezing temperature difference was 15 ℃ − (− 18 ℃) and the concentrations of Cu(II) were 0.025 mol/L and 0.0125 mol/L. The breakthrough experiment using a propylene/propane mixture (V_C3H6/V_C3H8 = 50/50) revealed that the Chitosan-Cu (0.025 mol/L) material exhibited a lower adsorption capacity for propane, as compared to its higher adsorption capacity for propylene. Therefore, the adsorption selectivity of propylene/propane reached an impressive 3.877, revealing the potential of carbon materials in the separation of propylene/propane.

Graphical abstract

Keywords: Chitosan; Copper; Propylene-propane; Adsorption separation

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-024-03422-5

Chemical Papers 78 (8) 4751–4765 (2024)