http://hdl.handle.net/2268.2/16790 Wed, 19 Aug 2026 04:10:16 GMT 2026-08-19T04:10:16Z http://hdl.handle.net/2268.2/26165 Title: Master Thesis : Development of short-cut cost correlations for CO2 capture technologies using data driven approaches: the case of the hot potassium carbonate process (including introduction to research methodology) Abstract: Post-combustion CO₂ capture by chemical absorption is the most mature and readily retrofittable route for decarbonising the existing industrial and power fleet, yet rapid economic screening across diverse CO₂ sources remains hampered by the need for case-by-case process simulation. While shortcut cost correlations exist for monoethanolamine (MEA) capture, none have been published for the unpromoted hot potassium carbonate (K₂CO₃) process, whose elevated-pressure operating regime remains largely unexplored. This thesis develops and validates the first shortcut cost correlation framework for unpromoted aqueous K₂CO₃ post-combustion capture. A rate-based Aspen Plus model employing the electrolyte non-random two-liquid (eNRTL) framework was used to perform a systematic CAPEX–OPEX optimisation over a a 20-point parametric grid spanning inlet CO₂ concentrations of 5 to 50 mol% and capture scales of 135 to 1500 kt CO₂/year with an absorber pressure between 4-50 bar. The optimal pressure, absorber height, and stripper height were identified at each point by minimising the total annualised cost per tonne of CO₂. From the resulting cost-optimised dataset, correlations were fitted expressing total equipment cost and specific utility consumption as explicit functions of CO₂ inlet concentration and flue gas molar flow rate, deliberately decoupled from final cost assembly so users can apply their own cost methodology and utility prices. The optimum capture cost falls roughly two-fold per step increase in concentration, from about 378 €/tCO₂ at 5 mol% to 65 €/tCO₂ at 50 mol% at the 1078 kt/year reference scale. The framework enables rapid economic screening of K₂CO₃ capture across a wide range of industrial CO₂ sources, while confirming that unpromoted K₂CO₃ remains comparable with MEA only at high inlet concentrations, motivating promoted formulations as future work. Sun, 28 Jun 2026 22:00:00 GMT http://hdl.handle.net/2268.2/26165 2026-06-28T22:00:00Z http://hdl.handle.net/2268.2/26162 Title: Master Thesis : Photocatalytic coatings for water purification from antibiotic contaminants (including introduction to research methodology) Abstract: The increasing presence of antibiotic contaminants in aquaculture wastewater poses significant risks to environmental and public health, particularly in intensive shrimp farming systems. This thesis focuses on developing photocatalytic coatings for water purification as part of the REMAOP project, which aims to implement sustainable and effective remediation technologies in shrimp ponds in Vietnam. Titanium dioxide (TiO₂) is a well-established photocatalyst due to its stability, low cost, and strong oxidative power; however, its efficiency in practical applications is often limited by low surface activity and difficulty in immobilization. The objective of this thesis is to design and fabricate a TiO₂-based photocatalytic coating capable of enhancing photocatalytic activity while ensuring strong adhesion to the inner walls of water-circulation pipes, where real-time decontamination occurs. The research will explore material modifications, coating strategies, and structural optimization to improve light absorption, charge separation, and overall degradation efficiency of antibiotic pollutants. The developed coating aims to provide a robust, scalable, and environmentally friendly solution for continuous water treatment in aquaculture systems, contributing to improved water quality and reduced antibiotic discharge in Vietnamese shrimp farming. Sun, 28 Jun 2026 22:00:00 GMT http://hdl.handle.net/2268.2/26162 2026-06-28T22:00:00Z http://hdl.handle.net/2268.2/26121 Title: Master Thesis : Synergistic visible-light photocatalysis by ZnO nanohybrids immobilized on activated halloysite for textile dyes degradation (including introduction to research methodology) Abstract: This study wanted to address the water pollution caused by textile azo dyes and synthesized advanced photocatalytic composite materials based on clay-supported ZnO nano hybrids for enhanced photocatalytic degradation of azo dyes, along with establishing their synergistic relationship. Due to the limited visible-light activity of ZnO in photocatalysis, different pure, metal-doped, and modified materials were synthesized,d and ZnO nanoparticles were successfully immobilized into them to form binary and ternary photocatalytic composite materials, i.e., ZnO nano hybrids, and tested for enhanced photocatalytic degradation of reactive black 5 (RB5) azo dyes in synthetic solution. Specifically, raw halloysite was modified by chemical treatment, and an activated clay (AC) was produced. Then, graphitic carbon nitride (g-C3N4) was synthesized and modified with Fe metal doping to form Fe/g-C3N4. After that, ZnO nanoparticles were synthesized using a precipitation process, and 4 different composite materials were formed, particularly [Fe/g-C3N4]/AC, ZnO/AC, [Fe/g-C3N4]/Zn, O, and [Fe/g-C3N4]/ZnO/AC. Then, 6 different analytical tests were carried out, namely SEM, XRD, DRS, Nitrogen adsorption-desorption, XP, S, and zeta potential for assessing the surface morphology, surface texture, crystal structure, optical properties, and surface charge, etc. of 8 synthesized materials. To evaluate the photocatalytic performance of 8 sample materials, photocatalytic experiments were carried out in the photocatalytic reactor for the degradation of RB5 azo dye under Visible light. The initial and residual concentrations of the dye were noted after 0, 2, 4, 6, and 8 h, and the RB5 degradation percentage was calculated. It was observed that the ternary composite [Fe/g-C3N4]/ZnO/AC is the best sample, showing a removal of 70% within 2 h, ending with the complete degradation of the azo dye after 8 h. For this sample, the RB5 degradation kinetic law was also determined, and a probable mechanism of RB5 dye degradation was proposed. To conclude, binary and ternary heterojunction composite materials like [Fe/g-C3N4]/ZnO and [Fe/g-C3N4]/ZnO/AC can enhance the photocatalytic performance of pure ZnO for the degradation of azo dyes, overcoming the barrier of limited visible light activity. Sun, 28 Jun 2026 22:00:00 GMT http://hdl.handle.net/2268.2/26121 2026-06-28T22:00:00Z http://hdl.handle.net/2268.2/25945 Title: Master Thesis : Investigation of Thermal Exposure on the Structural and Optical Properties of Textiles (including introduction to research methodology) Abstract: .This thesis investigated the effects of thermal exposure on the structural, optical, and mechanical properties of market, recycled, and post-consumer textile materials. Textile products are frequently exposed to heat during manufacturing and daily-use processes such as drying, finishing, and ironing, which could lead to discoloration, degradation, and loss of performance. The study focused on different textile compositions, including virgin and recycled cotton, virgin and recycled polyester, poly-cotton blends, and post-consumer textile products. Thermal treatments were applied under controlled conditions to evaluate the relationship between fiber composition and property changes after heat exposure. Structural and surface modifications were analysed using SEM-EDX, optical microscopy, FTIR spectroscopy and TG-DSC. In addition, tensile strength testing was performed to determine the impact of thermal aging on mechanical performance. The results contributed to the development of more sustainable textile materials while supporting improved recycling strategies and enhanced durability of textile products in circular economy applications. Sun, 28 Jun 2026 22:00:00 GMT http://hdl.handle.net/2268.2/25945 2026-06-28T22:00:00Z