Oxidative desulphurisation using cavitation and complimentary techniques

Abstract

This thesis focuses on developing a viable means for removing thiophene’s from fuels. New results are presented on oxidizing single ring thiophenes in a model fuel with only water over an extended range of volume fraction of organic phase from 2.5 to 80 v/v % in HC systems. The influence of type and scale of HC device on performance of oxidative desulphurization is also presented and aeration was utilised as an enhancement technique. HC was shown to be able to remove single ring thiophenes from dodecane without using any external catalyst or additives, however, in absence of catalyst or additives, it was not possible to remove dual ring thiophenes such as dibenzothiophene using HC. Therefore, in the second phase of this work, various strategies based on use of catalyst or additives to augment cavitation-based process were investigated. AC based experiments were opted for shortlisting suitable catalysts and additives for intensifying cavitation-based processes. The influence of using oxidant (H2O2) and carboxylic acid catalysts on efficacy of removal of dual ring thiophenes is presented in Chapter 3. Chapter 4 focuses on investigation of enhancement strategies for improving oxidation such as aeration, UV, photocatalysis and regeneration of solvents utilising on Oxidative Desulphurisation. Optimal results from the AC based studies with additives were then scaled up in a HC system for oxidation of dual ring thiophenes with n-dodecane and n-hexane as model fuels and typical transport fuels (diesel, kerosene, and petrol). The observed performance with HC was compared with results obtained from a stirred tank and AC set-up. The presented data indicates that HC is able to intensify oxidation of sulphur species. The presented results provide a sound basis for further developments on HC based oxidative desulphurization processes.

Date of Award	Jul 2024
Original language	English
Awarding Institution	Queen's University Belfast
Sponsors	Northern Ireland Department for the Economy
Supervisor	David Rooney (Supervisor) & Peter Robertson (Supervisor)