Novelty synthesis of MOFs based mixed matrix membranes for mixture gases separation
Bachelor’s / Master’s Thesis
as soon as possible
Background and motivation
Gas separation are essential processes in the energy and petrochemical industrials (including olefins/paraffins separation, CO2 separation in terms of pre-combustion (CO2/H2 separation) and post-combustion (CO2/N2 separation), oxyfuel combustion (O2/N2 separation), and natural gas purification). Compared with traditional technology (amine adsorption CO2 from natural gas, fractional distillation for olefins from paraffins et. al.), membrane separation offers a potentially more energy efficient technology with smaller capital cost and physical footprint, as well as minimal environmental concerns.
Mixed matrix membranes (MMMs) formed by dispersing highly selective molecular sieve particles (filler phase) in a continuous polymer matrix are promising approaches that combine the ease of processing polymeric membranes with the superior separation performance of molecular sieving materials. With appropriate choice of polymer and molecular sieve, MMMs able to overcome the Robeson upper bound of pure polymeric materials for permeability and selectivity. Metal–organic frameworks (MOFs) consisting of metal ions/clusters connected by organic linkers represent an important class of crystalline porous materials with potential molecular sieving properties for gas separations, owing to the relatively flexible and tunable pore size and pore structure.
However, MMMs often do not operate at their predicted separation performance behavior, due to an insufficient adhesion between the polymer matrix and the MOFs. The two main issues that may influence membrane performance are poor compatibility between the MOF fillers and polymer matrices (leading to interface defects) and particle agglomeration and sedimentation (resulting in nonselective voids and brittle membranes). Therefore, Membranes with uniform and defect-free structures are desirable, especially for separation applications. In order to address these problems, our aim is to develop the novelty synthesis methods (include the selection of suitable polymer and MOFs) and further optimize the synthesis conditions to prepare defect free MOFs-MMMs composite membranes for mixture gases separation.
This work is mainly experimental and based on the combined knowledge of polymer chemistry and membrane technology. The following specific task will be performed as part of the project:
- Literature review on the topic (MOF based MMMs with a focus on the novel membrane materials and the related synthesis process, membranes application in the mixture gases of CO2/N2, ethene/ethane and propene/propane separations).
- Preparation of MOFs based MMMs via membrane casting technology.
- Characterization of the synthesized MOFs, pure plyometric membranes and MOFs based MMMs.
- Perform the gas separation experiments with pressure-decay and mixed gas separation system to evaluate the membrane permeability and separation performance.
Start date: as soon as possible
Examiner: Dr. Bradley Ladewig email@example.com
Supervisor: Dr. Jinju Zhang
Contact: Jinju.firstname.lastname@example.org Tel: 0721/608-24088