Synergetic thermodynamic/kinetic separation of C₃H₈/CH₃F on carbon adsorbents for ultrapure fluoromethane electronic gas

Abstract

Atomic layer etching (ALE) using the environmentally friendly electronic gas fluoromethane (CH3F) is guided for fabricating nanoscale electronic components. The adsorptive purification of CH3F provide a viable direction to remove trace amounts of impurities to produce highly pure CH3F (>99.9999%) for the ALE process. Herein, to remove trace propane (~100 ppm) in CH3F, we report synergetic thermodynamic and kinetic separation of C3H8/CH3F over glucose‐derived carbon molecular sieve CMS‐T, (T as pyrolysis temperature). With pore size slightly larger than the kinetic diameter of C3H8, CMS‐600 allows both strong confined adsorption of C3H8 and a higher diffusion rate of C3H8 over CH3F, resulting in a remarkable separation factor of 51.1. Breakthrough experiment demonstrates a high dynamic production capacity of 457 L kg−1 of 7 N CH3F (<100 ppb of C3H8) over CMS‐600 with excellent cycling stability. Adsorption purification over carbon provides a feasible approach for industrial hyperpurification of electronic gas.

2D MOF with multifunctionalized catalytic sites for one‐pot tandem synthesis of cyclic carbonates from olefins and CO2

“…Noticeably, bulk Zr‐BTB displayed almost no micropores and very few mesopores (Figure 2B), however, the formation of densely packed layers may cause transformation of pores to a smaller size 31 . With a smaller molecular size of 3.3 Å than that of N 2 , CO 2 was further applied as the probing gas to analyze the adsorption behaviors 32 . From CO 2 isotherms at 195 K, the microporous volumes were calculated as 0.12, 0.23, and 0.24 cm 3 g −1 for bulk Zr‐BTB, 2D Zr‐BTB, and Zr‐BTB/PA‐Co, respectively (Table 1).…”

“…31 With a smaller molecular size of 3.3 Å than that of N 2 , CO 2 was further applied as the probing gas to analyze the adsorption behaviors. 32 From CO 2 isotherms at 195 K, the microporous volumes were calculated as 0.12, 0.23, and 0.24 cm 3 g À1 for bulk Zr-BTB, 2D Zr-BTB, and Zr-BTB/PA-Co, respectively (Table 1). The comparation with the results from N 2 tests demonstrated that some inherent micropores cannot be detected by N 2 probe.…”

Influence of Structural Domain Evolution in Carbon Materials on the Selective Separation of Alkenes from Alkanes

“…7 Adsorptive separation is considered as a potential alternative technology with broad prospects owing to its energy-and cost-effective features. 8,9 Adsorptive separations based on porous adsorbents can mainly be divided into three categories, including equilibrium separation, 10,11 kinetic separation, 12,13 and molecular sieving. 14−16 It is well known that the molecular sieving mechanism can realize superior separation efficiency.…”

Porous materials with suitable pore size and dual‐functional sites for benchmark one‐step ethylene purification

“…The significant advance in porous materials [5][6][7][8][9][10][11][12][13][14][15][16][17] in the last decade has aroused interests of researchers to seek adsorptive separations to make the challenging separation processes more energy-efficient. The developed ordered-assembly porous materials, like metal-organic frameworks (MOFs), [18][19][20][21][22][23][24] covalent organic frameworks (COFs), 25,26 etc, provide an excellent platform for tailor-made porous materials that are adaptive for different guest molecules and have obtained considerable achievements in C 2 H 4 purification.…”