Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

A computational modelling study of chlorine dioxide and its role in water purification cycles

Thesis (PhD (Chemistry))--University of Pretoria, 2023.

Saved in:
Bibliographic Details
Other Authors: Pretorius, J.A.
Format: Thesis
Language:English
Published: University of Pretoria 2023
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613718388408320
access_status_str Open Access
author2 Pretorius, J.A.
author_browse Pretorius, J.A.
author_facet Pretorius, J.A.
collection Thesis
dc_rights_str_mv © 2023 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.
description Thesis (PhD (Chemistry))--University of Pretoria, 2023.
format Thesis
id oai:repository.up.ac.za:2263/93452
institution University of Pretoria (South Africa)
language English
last_indexed 2026-06-10T12:40:36.114Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2023
publishDateRange 2023
publishDateSort 2023
publisher University of Pretoria
publisherStr University of Pretoria
record_format dspace
source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/93452 A computational modelling study of chlorine dioxide and its role in water purification cycles Pretorius, J.A. natasha.misheer@gmail.com Misheer, Natasha UCTD Ab initio Chlorine dioxide Quantum Water purification Chemical structure geometries Natural and agricultural sciences theses SDG-06 SDG-06: Clean water and sanitation Thesis (PhD (Chemistry))--University of Pretoria, 2023. This study involves the computational investigation into the perceived reactivity of a group of sixty (60) sub- and extended- chlorine oxide species with the general formulae of CℓxOy applied to water purification. In order to achieve the ultimate objective of elucidating their chemical role in aqueous media, acting as oxidative agents, an intensive computational approach has been followed to determine their thermochemical properties. The extended species of CℓO2 display a complex sequence of bonding character with an appreciable charge dissipation (extracted as partial charges), which complicates the effective selection of basis sets and electronic structural optimization, during Ab Initio analyses. Besides a single molecular computational analysis, an alternative grand canonical ensemble approach was introduced, applying Gibbs ensemble Monte Carlo simulations, supported by revised force field parameters to derive at optimum model sizes. In this context, this approach proved highly efficient, resulting in consistent thermochemical properties for all species, through optimum selection of Hamiltonians and appropriate basis sets, during quantum chemical analyses. Excellent correlations with published Heat of Formation energies were obtained for almost all the ensemble derived species. A few energy discrepancies identified during Ab Initio (VASP and Gaussian software) calculations will need to be investigated more thoroughly in a further study. Chemical structure geometries were typically maintained for all models and self-consistency reached in all the quantum chemical refinement cycles. Some of these species are presented as radical and ionic entities, which complicates their quantum atom potential representations. This observation specifically applies to species exhibiting variable spin conditions. This spin variability can further promote spin contamination, through extensive polarization contributions. Charged species were unfortunately not exposed to empirical ensemble simulations (reasons given) and had to be considered as single molecular entities Chemistry PhD (Chemistry) Unrestricted Faculty of Natural and Agricultural Sciences SDG-06:Clean water and sanitation 2023-11-27T06:00:53Z 2023-11-27T06:00:53Z 2024-04 2023 Dissertation * April 2024 http://hdl.handle.net/2263/93452 DOI: https://doi.org/10.25403/UPresearchdata.24630918.v1 https://doi.org/10.25403/UPresearchdata.24630918 en © 2023 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University of Pretoria
spellingShingle UCTD
Ab initio
Chlorine dioxide
Quantum
Water purification
Chemical structure geometries
Natural and agricultural sciences theses SDG-06
SDG-06: Clean water and sanitation
A computational modelling study of chlorine dioxide and its role in water purification cycles
title A computational modelling study of chlorine dioxide and its role in water purification cycles
title_full A computational modelling study of chlorine dioxide and its role in water purification cycles
title_fullStr A computational modelling study of chlorine dioxide and its role in water purification cycles
title_full_unstemmed A computational modelling study of chlorine dioxide and its role in water purification cycles
title_short A computational modelling study of chlorine dioxide and its role in water purification cycles
title_sort computational modelling study of chlorine dioxide and its role in water purification cycles
topic UCTD
Ab initio
Chlorine dioxide
Quantum
Water purification
Chemical structure geometries
Natural and agricultural sciences theses SDG-06
SDG-06: Clean water and sanitation
url http://hdl.handle.net/2263/93452
https://doi.org/10.25403/UPresearchdata.24630918