Effect of density change on flux response systems

  • Alexis MCDONALD

Student thesis: Doctoral Thesis


Flux response technology is a technique for using differential measurements of flow rates as changes occur caused by adsorption, reaction and desorption in a continuous flow reactor. This work looks at using a gas chromatographic column as the reactor and uses the concepts of capillary and perturbation viscometry to quantify the effects of density change on fluxresponse on the reactor. Experiments were conducted using basic equipment including a volume and different resistance set up in a Wheatstone bridge arrangement so that differential measurements can be obtained. Firstly, changes were made by perturbing the flow into the system with pressure. Secondly, changes were made to the system by perturbing with a gas flow. Measurements were taken using a differential pressure transducer (DPT) to measure the flux response and the results were used to determine the volume in the system. Further experiments were conducted to validate theoretical derivations of the operation of a gas density detector (GDD) which could be used as a gas chromatographic detector. Experiments using nitrogen and argon as the main and perturbation gases were completed. Results were obtained using the DPT and the GDD and verified the theoretical derivations. The results showed that when the perturbation gas is of a higher density to that of the main gas, there is a distinct positive step in the both the DPT and GDD readings. There is negative step when the perturbation gas has a lower density which was as expected. Helium experiments proved problematic as there were potential issues with viscosity change affecting the detector response producing some anomalous results so further work is required to investigate this. Additional work using different gas components would be advantageous.
Date of Award21 Sep 2018
Original languageEnglish
Awarding Institution
  • University Of Strathclyde
SupervisorEsther Ventura-Medina (Supervisor) & Miguel Jorge (Supervisor)

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