Enhanced adsorption purification of fluoromethane electronic gas using carbon adsorbent with rich ultramicroporosity

• Published in: Chemical engineering science 2024-08, Vol.296, p.120250, Article 120250
• Main Authors: Wei, Xuan, Du, Shengjun, Huang, Jiawu, Peng, Junjie, Liao, Jiamin, Fu, Zhuhong, Chen, Yanshan, Liu, Zewei, Miao, Guang, Liao, Neng, Xiao, Jing
• Format: Article
• Language: English
• Subjects: Adsorption purification; Carbon; Electronic gas; Pore size; Ultramicroporosity
• ISSN: 0009-2509; 1873-4405
• DOI: 10.1016/j.ces.2024.120250

•Highly-efficient purification of CH3F electronic gas was realized using carbon adsorbent C-HCP-1.•C-HCP-1 performs C3H8 uptake of 0.164 mmol g−1 at 0.01 kPa and 298 K, and record C3H8/CH3F IAST selectivity up to 40.0.•C-HCP-1 demonstrates one-step CH3F purification from 4 N to 7 N-grade with a CH3F breakthrough capacity of 3715 L kg−1. Ultra-pure fluoride electronic gas is an indispensable cleaning and etching gas in the semiconductor industry. Adsorptive separation based on porous materials can be a promising technology to effectively separate ultra-pure CH3F (>99.9999 %) from trace C3H8 impurity (∼100 ppm). Herein, a series of glucose-derived carbon adsorbents (GCAs) were prepared using a combination strategy of pre-oxidation and KOH activation. Among obtained adsorbents, C-HCP-1 showed a high micropore surface area of 1472 m2 g−1 and ultramicropore ( 0.98) has been observed between C3H8/CH3F selectivity and ultramicropore volume. Breakthrough experiments verified that 7 N-grade CH3F could be produced from C3H8/CH3F mixtures (1/9999, v/v) with a record productivity of 3715 L kg−1. Meanwhile, excellent cycle stability and moisture stability suggest C-HCP-1 as a competitive candidate for highly-efficient purification of industrial electronic gas.