Preparation, characterisation and application of ordered mesoporous materials
Abstract
The history of ordered mesoporous materials starts with the discovery of MCM-41(Mobil
Composition of Matter-41) in 1992 using an organic template as structure directing agent.
Mesoporous materials have not only proved to be ideal candidates in various fields like,
for example, catalysis but could also be potentially used as a hard template for
synthesising other useful mesoporous materials. The aim of this research was to develop
industrially feasible and environmentally friendly methods for the preparation of ordered
mesoporous materials, to characterise these and to study their applications. The main
techniques used for the characterisation of these mesoporous materials were N₂
physisorption, XRD and TEM. In the first part of the study, metal- and halogen-free
ordered mesoporous polymer and carbon materials having 2D hexagonal (P6mm) and
body centered cubic (Im3̅m) mesostructures were made using a modified two phase
method employing alternative polymerisation and condensation catalysts. These
materials had high surface area and pore volume and had narrow pore size distributions.
Their physical evolution with increasing calcination temperature was examined as were
the effects of varying synthesis parameters on the nature of the final mesostructure. The
second part of the study was focused on the synthesis of ordered mesoporous ceria using
metal- and halogen-free ordered mesoporous carbon materials - made in the first part of
the study - as the hard template. The mesoporous ceria having 2D hexagonal arrangement
of pores were successfully synthesised using a solid-liquid method which is a solvent
free, easy to use and environmentally friendly method. The carbon template calcined at
400 °C was found to be the best template in terms of giving high loading of precursor and
giving high quality product. The synthesis of body centered cubic ceria was less
successful than hoped due to the small pore openings in this template material. The third
part of study involved the preparation of mesoporous carbon supported Pd catalysts and
their use in the hydrodechlorination of trichloromethane (TCM). The results were very
promising, and 100 % conversions were obtained at 175 °C with high selectivity to
alkanes and low selectivity to intermediate chlorinated products.
Type
Thesis, PhD Doctor of Philosophy
Rights
Embargo Date: 2021-03-20
Thesis restricted in accordance with University regulations. Print and electronic copy restricted until 20th March 2021
Thesis restricted in accordance with University regulations. Print and electronic copy restricted until 20th March 2021
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