• Khalid Althumayri

Student thesis: Phd


Membrane-based gas separation processes are an area of interest owing to their high industrial demand for a wide range of applications, such as natural gas purification from CO2 or H2, and N2 or O2 separation from air. This thesis is focused on developing and investigating polymeric-based membranes. Firstly, novel mixed matrix membranes (MMMs) were prepared, incorporating few-layer graphene in the polymer of intrinsic microporosity PIM-1. Secondly, novel polyphenylene-based polymers of intrinsic microporosity (PP-PIMs) were synthesised.An optimum preparation method of graphene/PIM-1 MMMs (GPMMMs) was established from numbers of experiments. In this study, graphene exfoliation was a step towards GPMMM preparation. Starting from graphene exfoliation in chloroform, as a good solvent for PIM-1, enhancement in graphene dispersibility was obtained with addition of PIM-1. This result helped in GPMMM preparation with high graphene content (up to 4 wt.%). Characterizations techniques such as Raman spectroscopy and scanning electron microscopy (SEM) of GPMMMs, confirmed the few layer graphene content, with morphology changes in the polymeric matrix compared to pure PIM-1.Gas permeability results of GPMMMs showed an enhancement in permeability with low loading graphene (0.1 wt.%) using a relatively low permeability PIM-1 batch, due to high water content. However, less influence of graphene incorporation on permeability was observed with a highly permeable PIM-1 batch. Reduction in permeability over time, termed an ageing effect, is known for a polymer of high-free volume like PIM-1. However, the enhancement of GPMMMs permeability after eight months storage was shown to be retained.Novel PP-PIMs were prepared from novel precursors using a series known organic reactions. PP-PIMs were divided into two groups of polymers based on their polymerization reactions. A group of polymers were prepared from condensation polymerization between bis-catecol monomers and tetrafluoroterephthalonitrile (TFTPN). Another group of polymers were prepared from Diels Alder polymerization between monomers of terminal bisphenylacetylene groups and bis tetraphenylcyclopentadienones (TPCPDs). All of which yielded polymers with apparent BET surface area in the range 290-443 m2 g-1.
Date of Award1 Aug 2016
Original languageEnglish
Awarding Institution
  • The University of Manchester
SupervisorPeter Budd (Supervisor) & John Gardiner (Supervisor)


  • Mixed matrix membranes
  • Polymers of intrinsic microporosity
  • Graphene
  • Gas permeation

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