Low temperature and facile synthesis of nitrogen-doped hierarchical porous carbon derived from waste polyethylene terephthalate for efficient CO2 capture

Shaojie Zhou; Haiyang Xu; Shurong Wang; Hongyu Feng; Yanjun Hu; Shicheng Zhang

doi:10.1016/j.scitotenv.2023.169856

Low temperature and facile synthesis of nitrogen-doped hierarchical porous carbon derived from waste polyethylene terephthalate for efficient CO₂ capture

Sci Total Environ. 2024 Mar 1:914:169856. doi: 10.1016/j.scitotenv.2023.169856. Epub 2024 Jan 6.

Authors

Shaojie Zhou¹, Haiyang Xu², Shurong Wang³, Hongyu Feng¹, Yanjun Hu⁴, Shicheng Zhang⁵

Affiliations

¹ State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.
² College of Advanced Materials Engineering, Jiaxing Nanhu University, Jiaxing 314001, China.
³ State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China. Electronic address: srwang@zju.edu.cn.
⁴ Institute of Thermal and Power Engineering, Zhejiang University of Technology, Hangzhou 310023, China. Electronic address: huyanjun@zjut.edu.cn.
⁵ Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China.

PMID: 38190916
DOI: 10.1016/j.scitotenv.2023.169856

Abstract

Waste polyethylene terephthalate (PET) with high carbon content (>60 wt%) has shown great potential in the field of synthesizing carbon materials for CO₂ capture, attracting increasing attention. Herein, an innovative strategy was proposed to synthesize nitrogen-doped hierarchical porous carbon (PC) for CO₂ capture using PET as precursor and sodium amide (NaNH₂) as both nitrogen dopant and low-temperature activator. As-synthesized N-doped PC exhibited a significantly high micropore volume of 0.755 cm³/g and a rich content of N- and O-containing functional groups, offering ample active sites for CO₂ molecules. Further, the adsorbents demonstrated excellent CO₂ capture capacity, achieving 5.7 mmol/g (0 °C) and 3.3 mmol/g (25 °C) at 1 bar, respectively. This was primarily attributed to the synergistic effect of narrow micropores filling and electrostatic interactions. Moreover, as-synthesized PC exhibited rapid CO₂ adsorption capability, and its dynamic adsorption process was effectively described using a pseudo-second-order kinetic model. After five consecutive cycles, PET-derived PC still maintained ~100 % of adsorption capacity. They also possessed good CO₂/N₂ selectivity and reasonable isosteric heat of adsorption. Therefore, as-synthesized nitrogen-doped PC is a promising CO₂ adsorbent through low-temperature activation of carbonized PET with NaNH₂. Such findings have substantial implications for waste plastic recycling and mitigating the greenhouse effect.

Keywords: Carbon dioxide capture; Nitrogen-doped porous carbon; Polyethylene terephthalate; Sodium amide activation.