eprintid: 10203575
rev_number: 14
eprint_status: archive
userid: 699
dir: disk0/10/20/35/75
datestamp: 2025-03-14 13:03:12
lastmod: 2025-03-14 13:03:12
status_changed: 2025-03-14 13:03:12
type: thesis
metadata_visibility: show
sword_depositor: 699
creators_name: Lin, Jiaqi
title: Plastic pyrolysis to organic liquids and gases using structured porous zeolitic solids and hierarchical analogues
ispublished: unpub
divisions: UCL
divisions: B04
divisions: C06
divisions: F56
note: Copyright © The Author 2025. Original content in this thesis is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) Licence (https://creativecommons.org/licenses/by-nc/4.0/). Any third-party copyright material present remains the property of its respective owner(s) and is licensed under its existing terms. Access may initially be restricted at the author’s request.
abstract: This thesis focuses on optimising mesopore design in zeolites, specifically FAU, MFI, and BEA frameworks, to mitigate diffusion limitations inherent in parent microporous structures. By employing a comprehensive suite of in situ and ex situ characterisation techniques, we aimed to enhance the understanding of mesopore formation and its impact on catalytic performance. The primary objective was to facilitate improved catalytic efficiency, specifically converting plastic waste to chemicals, through strategic design and modification of the microporous aluminosilicate to contain mesopores along with micropores.
The catalytic performance of both parent and treated (hierarchical) zeolites was evaluated through the pyrolysis of various plastics, ranging from polyethylene (PE), including both high-density (HDPE) and low-density (LDPE) variants, to polypropylene (PP) and polystyrene (PS). This study systematically investigated the influence of zeolite modifications on the pyrolysis process, assessing the yield and chemical distribution of the resultant liquid, solid, and gaseous products. The goal was to identify a correlation between zeolite acidity and porosity with the product distribution, thereby establishing a trend that could guide future catalyst design.
Moreover, the recyclability of zeolites was examined by analysing post-catalytic coking using solid-state NMR. This analysis aimed to elucidate the coking mechanisms within the catalysts, providing insights into how coking can be minimised in future iterations. By understanding the nature and location of coke deposition, strategies could be developed to enhance the longevity and efficiency of zeolite catalysts in plastic pyrolysis applications.
In conclusion, this thesis presents a thorough investigation into the optimisation of mesoporous zeolites for catalytic applications, highlighting the critical relationship between acidity, porosity, and catalytic performance. The findings offer valuable contributions towards the development of more efficient, durable, and recyclable zeolite-based catalysts, paving the way for improved processes in the catalytic pyrolysis of plastics.
date: 2025-01-28
date_type: published
full_text_type: other
thesis_class: doctoral_embargoed
thesis_award: Ph.D
language: eng
verified: verified_manual
elements_id: 2352217
lyricists_name: Lin, Jiaqi
lyricists_id: JLINA69
actors_name: Lin, Jiaqi
actors_id: JLINA69
actors_role: owner
full_text_status: restricted
pages: 257
institution: UCL (University College London)
department: Chemistry
thesis_type: Doctoral
editors_name: Sankar, Gopinathan
citation:        Lin, Jiaqi;      (2025)    Plastic pyrolysis to organic liquids and gases using structured porous zeolitic solids and hierarchical analogues.                   Doctoral thesis  (Ph.D), UCL (University College London).    
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10203575/9/Lin_10203575_Thesis.pdf