Abstract

1.1.1.2-Tetrafluoroethane (R134a) is developed as a tracer for mechanical leakage detection in military chemistry. Due to the weaker physical adsorption properties, water vapor competitive adsorption limits the use of tracer R134a. Thus, it is urgent to the analyze dynamic competitive adsorption behavior of R134a and water vapor on the activated carbon. In this study, R134a breakthrough curves on the fixed beds packed with activated carbons under different relative humidity and moisture content levels were systematically measured. Combining mass spectrometry, gas chromatography, and a novel fiber Bragg grating temperature sensor, the dynamic competitive adsorption processes and axial temperature of fixed beds were first reported. Interestingly, with increasing moisture content, R134a breakthrough time decreased, but dynamic adsorption capacity increased. This was attributed to the fact that the residual water vapor could increase the specific surface area and pore volume of activated carbon to enhance R134a dynamic adsorption capacity. Using the R134a as the standard, the dynamic competitive adsorption process was first revealed and could be divided into four stages including Co-adsorption, Co-breakthrough, Competitive Adsorption (“Rolling Up” and “Adsorption Platform”), and Dynamic Adsorption Equilibrium. “Rolling Up” and “Adsorption Platform” phenomena are mainly determined by the strength of intermolecular interactions, the concentration difference of adsorbate, and the thermal effect induced by water vapor adsorption/desorption.

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 call

Disclaimer: 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.