Abstract
The separation of C3H4/C3H6 is one of the most energy intensive and challenging operations, requiring up to 100 theoretical stages, in traditional cryogenic distillation. In this investigation, the potential application of two MOFs (SIFSIX-3-Ni and NbOFFIVE-1-Ni) was tested by studying the adsorption-desorption behaviors at a range of operational temperatures (300–360 K) and pressures (1–100 kPa). Dynamic adsorption breakthrough tests were conducted and the stability and regeneration ability of the MOFs were established after eight consecutive cycles. In order to establish the engineering key parameters, the experimental data were fitted to four isotherm models (Langmuir, Freundlich, Sips and Toth) in addition to the estimation of the thermodynamic properties such as the isosteric heats of adsorption. The selectivity of the separation was tested by applying ideal adsorbed solution theory (IAST). The results revealed that SIFSIX-3-Ni is an effective adsorbent for the separation of 10/90 v/v C3H4/C3H6 under the range of experimental conditions used in this study. The maximum adsorption reported for the same combination was 3.2 mmol g−1. Breakthrough curves confirmed the suitability of this material for the separation with a 10-min gab before the lighter C3H4 is eluted from the column. The separated C3H6 was obtained with a 99.98% purity.
Highlights
Accepted: 16 April 2021Separation processes in the oil, gas and chemical industries account for up to 15%of their total energy requirements [1,2,3,4]
In this study, a systematic approach was considered to study the effect of two types of pyrazine-based inorganic anions SiF6 2−, NbOF5 2− ) metal organic frameworks (SIFSIX-3-Ni and NbOFFIVE1-Ni) under a range of temperatures (300–360 K) and pressures for the separation of propyne/propylene in various concentrations (10/90 v/v)
Both the Freundlich and Langmuir models represented the data between the other adsorbent adsorbate combinations. This may have been due to stronger monolayer type interactions between the propyne and SIFSIX compared to the NbOFFIVE gas system
Summary
Separation processes in the oil, gas and chemical industries account for up to 15%. of their total energy requirements [1,2,3,4]. These materials are based on 3D Zn/Cu/Ni coordination networks that contain metal nodes in addition to organic linkers Anions such as SiF6 2− (SIFSIX), NbOF5 2− (NbOFFIVE) form bridges in the MOF structure and are reported to have potential application in gas separations, such as. C3 H4 /C3 H6 separation was reported using [Cu(4,40 -bipyridine)(trifluo-romethanesulfonate (OTF)- 2 ](ELM-12) [21] This material showed good potential for adsorption selectivity through the estimation of the ideal adsorbed solution theory (IAST) selectivity at a trace concentration of propyne (ratio 1/99 C3 H4 /C3 H6 ), with good adoption capacity at lowpressure range. In this study, a systematic approach was considered to study the effect of two types of pyrazine-based inorganic anions SiF6 2− , NbOF5 2− ) metal organic frameworks (SIFSIX-3-Ni and NbOFFIVE1-Ni) under a range of temperatures (300–360 K) and pressures (up to 100 kPa) for the separation of propyne/propylene in various concentrations (10/90 v/v). Dynamic studies were conducted and breakthrough curves were established at varying numbers of cycles
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
