Chemical Engineering Commons^™

Tarnish Resistance Of Silver Reinforced With Carbon Material To Artificial Sweat And Hydrogen Sulfide, Kunthida Chanthaban

Chulalongkorn University Theses and Dissertations (Chula ETD)

Due to its immense popularity, silver jewelry has undergone continual development, it an intriguing product. The most significant issue with silver jewelry is the tarnish of the silver metal's surface. Therefore, using a coin making technique, the study team evaluated the properties of silver metal reinforced by carbon materials. To evaluate the silver's to sweat and hydrogen sulfide tarnishing. Effects of adding carbon to samples after performing an artificial sweat test. It was discovered that the use of highly scattered carbon improved the ability to remove tarnish from fake sweat because it reduced the surface area of the silver (Ag) …

Effect Of Dispersion Of Carbon Nanotubes On Electrical Conductivity And Compressive Strength Of Cnt/Cement Composite, Rittikiat Wandaw

Chulalongkorn University Theses and Dissertations (Chula ETD)

Carbon nanotubes (CNTs) are promising nanomaterials due to their exceptional properties, including high electrical, mechanical, and stability characteristics. These advantageous features position CNTs as suitable candidates for diverse applications, particularly in additive formulations designed to enhance overall performance. One notable application is their use in cement composites to improve mechanical and electrical properties. However, the hydrophobic property of CNTs presents challenges for dispersion within the hydrophilic cement matrix. Consequently, methods have been developed to aid CNT dispersion in both water and cement matrices. In this thesis, Triton X-100 employed as a surfactant, was used to disperse CNTs in water using …

Activity And Stability Of Tio2-Encapsulated Cspbbr3/Cs4pbbr6 For Photocatalytic Degradation Of Rhodamine B, Nutzeya Plainoen

Chulalongkorn University Theses and Dissertations (Chula ETD)

Due to the excellent optoelectronic performance of cesium lead bromide(CsPbBr3), it has shown promising potential as a photocatalyst for the degradation of organic compounds under sunlight. During the synthesis of CsPbBr3, Cs4PbBr6, another formation of CsPbBr3, is also produced, which exhibits desirable properties such as strong and narrow photoluminescence (PL) and enhanced thermal stability. In this study, we successfully synthesized a mixture of CsPbBr3/Cs4PbBr6 nanoparticles using a simple precipitation method. However, the stability of CsPbBr3/Cs4PbBr6 was found to be sensitive to high temperatures, moisture, and oxygen, which could affect its photocatalytic degradation performance. To enhance both stability and activity, we …

Effect Of Type And Concentration Of Acid On Characteristics Of Functionalized Biochar And Its Performance In Converting Fructose To 5-Hmf, Pimlapas Bunwichian

Chulalongkorn University Theses and Dissertations (Chula ETD)

Biomass, with its high cellulosic content, represented renewable source capable of being converted into essential platform chemicals like 5-hydroxymethylfurfural, levulinic acid, formic acid, and furfural. Currently, conversion of fructose to 5-HMF was achievable through various acid homogeneous catalysts. Although these catalysts yield higher outputs, they might pose challenges in recycling and corrosion issues. This thesis's novel approach involved preparing heterogeneous catalysts through pyrolysis and hydrothermal treatment of watermelon rind to create watermelon rind biochar (WB). Subsequently, WB underwent functionalization using HCl, H2SO4, and H3PO4 at concentrations of 1.6, 3.2, and 4.8N, respectively, at temperatures of 150 °C. These treated WB …

A Comparative Study Of Sustainable Aviation Fuel Production From Hydroprocessing Process Between Hydrogen Recovery Unit From Steam Reforming And Hydrogen Generation Unit From Biomass Gasification, Praeva Pongsripipat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Sustainable aviation fuel (SAF) can be generated using various processes. Among the well-established approaches, one that stands out is the hydrotreating of esters and fatty acids (HEFA). However, the HEFA process requires a source of hydrogen for the hydroprocessing reactions. Hydrogen is often considered as an expensive component, and its cost can have a significant impact on the overall economic viability of renewable aviation fuel production. In this work, the SAF process is developed using Aspen Plus simulation. There are 2 scenarios to be considered. Scenario 1 involves a plant in which the hydrotreating of palm oil is performed to …

Carboxymethyl Cellulose As Artificial Solid/Electrolyte Interphases And Separator For Zn-Based Battery, Phonnapha Tangthuam

Chulalongkorn University Theses and Dissertations (Chula ETD)

As the quest for robust large-scale energy storage systems (EESs) intensifies, aqueous rechargeable zinc-based batteries are gaining traction for grid-scale applications due to their high theoretical capacity and safety. Despite this, their practical application is compromised by several zinc anode issues, including hydrogen evolution, corrosion, dendritic growth, and passivation. An artificial solid electrolyte interphase (ASEI) using polyelectrolytes, such as carboxymethyl cellulose (CMC), is emerging as a solution, offering economic and environmental advantages. CMC's structure, enriched with carboxyl groups, allows for the refined management of zinc ion distribution at the electrode surface, promising enhanced surface stability. This study delves into CMC's …

Techno-Economic Analysis And Intensification Of Biosurfactant Production From Palm Fatty Acid For Oil Recovery Enhancement, Chanapol Charoentanaworakun

Chulalongkorn University Theses and Dissertations (Chula ETD)

Currently, Biosurfactants are receiving the interest as a substitute for surfactants synthesized from petroleum products due to their biodegradability. Palm oil derivatives are one of the interesting candidates of biosurfactant production because of the superior properties of hydrocarbon structure in the range of C16-C18. Thus, this research studied the economic and environmental impact analysis of production processes, and adsorption and oil recovery performance for different anionic biosurfactants synthesized from palm oil derivatives, i.e. palm fatty acid distillate (PFAD). Moreover, the optimal design and essential operating condition of batch reactive distillation column were also studied to intensify the equilibrium limitation of …

Green Synthesis For Silver Nanoparticle /Natural Rubber/ Nanocellulose Bio-Polymeric Composites, Puttakhun Meemai

Chulalongkorn University Theses and Dissertations (Chula ETD)

A green synthesis method was developed to produce biobased semiconducting composites of silver nanoparticles (AgNPs), skim natural rubber (SNR), and bacteria cellulose. A solution of silver nitrate (AgNO3) ranging from 40 to 160 mM was added to skim natural rubber latex (SNRL) to facilitate the reduction of silver ions to AgNPs at temperatures between 50 and 80 °C. Subsequently, BC pellicle was immersed in the prepared AgNPs-SNRL suspension for 48 hours, followed by washing and drying. The resulting AgNPs/SNR/BC films were then analyzed for their chemical, mechanical, antibacterial, and electrical properties. The strain at break of the films was significantly …

Sustainable Toughening Of Polylactic Acid With Ultra-Fine Fully Vulcanized Powdered Natural Rubber, Reza Gholami

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study investigated the sustainable toughening of polylactic acid (PLA) by incorporating ultra-fine fully vulcanized powdered natural rubber graft-copolymerized with poly-styrene-co-acrylonitrile (UFPNR-SAN). We investigated the effect of the styrene-to-acrylonitrile ratio (ST:AN) used during the grafting process on the final UFPNR-SAN compatibility with PLA. The ST:AN ratio was systematically varied during the grafting reaction to prepare UFPNR-SAN with a range of different surface energies. The ST:AN ratio of 4:1 resulted in higher compatibility of UFPNR-SAN with the PLA matrix among other ratios. This could be explained by the desirable interfacial interactions and better dispersion shown by the contact angle measurements and …

Shape Memory Polymer Based On Copolybenzoxazines: Effects Of Chain Length Of Aliphatic Monoamines On Shape Memory Performance, Attachai Sriwattana

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research was successful in completely synthesizing benzoxazine copolymers for shape memory polymers (SMPs) by mixing bisphenol A-aniline (BA-a) and bisphenol A-aliphatic monoamines of various chain lengths (BA-aMAs). Our studies have shown that shorter chain lengths will provide higher crosslinking densities, which play an important role in promoting the stiffness of the polymer, resulting in a higher shape-fixity ratio (Rf). While longer chains result in a lower crosslinking density and a larger free volume, thus promoting a higher shape-recovery ratio (Rr), Therefore, selecting the appropriate aliphatic monoamine chain length is crucial. From the study of this work, it was found …

Methyl Isobutyrate Production Via Hydrogenation Of Methyl Methacrylate Derived From Pyrolysis Of Acrylic Plastic Waste, Ramzi Nasser Ahmed Saif

Chulalongkorn University Theses and Dissertations (Chula ETD)

According to zero waste and upcycling policy, this work aims to utilize waste polymethyl methacrylate (PMMA) to methyl isobutyrate (MIB) via hydrogenation over nickel (Ni) based catalysts supported on commercial zeolites: HY, H-Beta-27 (SiO2/Al2O3 = 27 by mole), H-Beta-40 (SiO2/Al2O3 = 40 by mole) and H-ZSM-5. The appropriate catalyst support was first screen by using MMA monomer as the substrate for hydrogenation. Under 30 bar initial H2 pressure (PH2) at 250 °C for 3 h, Ni/H-Beta-27 catalyst effectively promoted hydrogenation to achieve 85% MMA conversion with 56.2 wt% MIB yield because of its larger external surface area and pore size. …

Phosphorus Release And Recovery From Simulated Ferric Wastewater Sludge, Aseel Alnimer

Theses and Dissertations (Comprehensive)

Phosphorus (P) is a fundamental element necessary for all life forms and a key component in the fertilizer industry. Meanwhile, the excessive load of P to water bodies due to human activities has the potential to promote eutrophication. Wastewater treatment plants remove P either biologically or chemically and produce P rich sludge which could be a potential renewable source for P. At present, commercial technologies exist for P recovery from biological wastewater sludge. However, P recovery from chemical sludge particularly iron(III)-phosphate (Fe-P) sludge generated in chemical P removal plants that use iron(III) salts remains a challenge.

This study explored, in …

Investigation Of Mechanical Regulation On Stat3 Activity And Mmp Production, Jaxson R. Libby

Honors Theses and Capstones

Transcription factor, STAT3, is inappropriately expressed in cancer cells, and has contrasting activation in 2D versus 3D microenvironments. 2D plates are often used for drug screening and do not always recapitulate in vivo responses. To combat inaccurate 2D drug studies, a 3D hydrogel was created to support the growth of cancer cells into a tumor-like environment. The hydrogel consists of a biocompatible dextran homopolysaccharide, cell adhesion RGD sequences, and crosslinker MMP labile peptides. A pH dependent reaction couples the RGD sequences to dextran then the polymers are crosslinked into a gel. Crosslinking is accomplished using terminal cysteine peptide sequences, allowing …

Experimental Study On The Mechanical Controlling Factors Of Fracture Plugging Strength For Lost Circulation Control In Shale Gas Reservoir, Chengyuan Xu, Lingmao Zhu, Feng Xu, Yili Kang, Haoran Jing, Zhenjiang You

Research outputs 2022 to 2026

The geological conditions of shale reservoir present several unique challenges. These include the extensive development of multi-scale fractures, frequent losses during horizontal drilling, low success rates in plugging, and a tendency for the fracture plugging zone to experience repeated failures. Extensive analysis suggests that the weakening of the mechanical properties of shale fracture surfaces is the primary factor responsible for reducing the bearing capacity of the fracture plugging zone. To assess the influence of oil-based environments on the degradation of mechanical properties in shale fracture surfaces, rigorous mechanical property tests were conducted on shale samples subsequent to their exposure to …

Application Of A Novel Green Nano Polymer For Chemical Eor Purposes In Sandstone Reservoirs: Synergetic Effects Of Different Fluid/Fluid And Rock/Fluid Interacting Mechanisms, Abbas K. Manshad, Alireza Kabipour, Erfan Mohammadian, Lei Yan, Jagar A. A., Stefan Iglauer, Alireza Keshavarz, Milad Norouzpour, Amin Azdarpour, S. Mohammad Sajadi, Siyamak Moradi

Research outputs 2022 to 2026

In this research, a novel natural-based polymer, the Aloe Vera biopolymer, is used to improve the mobility of the injected water. Unlike most synthetic chemical polymers used for chemical-enhanced oil recovery, the Aloe Vera biopolymer is environmentally friendly, thermally stable in reservoir conditions, and compatible with reservoir rock and fluids. In addition, the efficiency of the Aloe Vera biopolymer was investigated in the presence of a new synthetic nanocomposite composed of KCl-SiO2-xanthan. This chemically enhanced oil recovery method was applied on a sandstone reservoir in Southwest Iran with crude oil with an API gravity of 22°. The Aloe Vera biopolymer’s …

Experimental Investigation Of The Interface And Wetting Characteristics Of Rock-H2-Brine Systems For H2 Geological Storage, Mirhasan Hosseini

Theses: Doctorates and Masters

The projected rise in demand for hydrogen (H2) production is a response to several factors, including greenhouse gas emissions caused by burning fossil fuels, depletion of fossil fuel reserves, and their uneven distribution around the earth. Thus, increased requirement for large-scale hydrogen storage solutions is anticipated to overcome imbalance between energy demand and supply. Deep underground formations such as salt caverns and porous reservoir rocks (e.g., depleted hydrocarbon reservoirs and deep saline aquifers) are necessary to achieve such volumes in practice. This process is known as underground hydrogen storage (UHS) which is technically very similar to underground natural gas storage. …

Comparative Study On Development Of Novel Catalytic Oxidation For Removing Emerging Contaminants, Abdul H. Asif

Theses: Doctorates and Masters

‘Wastewater treatment’ is not itself a new concept, where global water bodies have been polluted since the evolution of mankind. As a result of human activities including domestic, industrial and commercial practices, levels of water pollution through aqueous contaminants are increasing every day. Moreover, rapid industrialisation and recent human progress has given rise to a new classification of pollution, that of emerging contaminants (ECs). Further, these chemicals are highly resistant to biodegradation and are capable of travelling, where they can penetrate from one part of the world to another. Whilst traditional wastewater treatment techniques, such as adsorption, might be effective …

Shale Wettability Characteristics Via Air/Brines And Air/Oil Contact Angles And Influence Of Controlling Factors: A Case Study Of Lower Indus Basin, Pakistan, Darya Khan Bhutto, Abdul Majeed Shar, Ghazanfer Raza Abbasi, Ubedullah Ansari

Research outputs 2022 to 2026

Wettability is the fundamental parameter that influences the productivity of hydrocarbon reservoirs. The knowledge of this regarding shale formation is yet inadequate; thus, detailed analysis is essential for successful development of such reservoirs. The Early Cretaceous Sembar formations in the Lower Indus Basin, Pakistan, is considered as the key target for energy exploration; however, it exhibits large uncertainties due to the lack of data availability. Sembar shales hold significant hydrocarbon volumes rich in organic content; however, prior to this, no comprehensive research has been conducted to quantify the wetting behavior of these shales. Thus, precise information about the wetting behavior …

Using Magnesium Oxide Nanoparticles In A Magnetic Field To Enhance Oil Production From Oil-Wet Carbonate Reservoirs, F. Amrouche, M. J. Blunt, Stefan Iglauer, M. Short, T. Crosbie, E. Cordero, D. Xu

Research outputs 2022 to 2026

Enhanced oil production can maximise yield from depleted reservoirs, and in the face of dwindling global oil reserves can reduce the need for exploratory drilling during the transition away from fossil fuels. A hybrid technique, merging a magnetic field (MF) and magnesium oxide (MgO) nanoparticles (NPs), was investigated as a potential method of enhancing oil production from oil-wet carbonate reservoirs. The impact of this hybrid technique on rock wettability, zeta potential, and interfacial tension was also investigated. Displacement experiments were carried out on oil-wet Austin chalk – a laboratory carbonate rock analogue – using MgO NPs in deionized water (DW) …

Photocatalytic Reforming Of Lignocellulose: A Review, Xinyuan Xu, Lei Shi, Shu Zhang, Zhimin Ao, Jinqiang Zhang, Shaobin Wang, Hongqi Sun

Research outputs 2022 to 2026

Biomass has been considered as a promising energy resource to combat the exhaustion of fossil fuels, as it is renewable, sustainable, and clean. Photocatalytic reforming is a novel technology to utilize solar energy for upgrading biomass in relatively mild conditions. This process efficiently reforms and recasts biomass into hydrogen and/or valuable chemicals. To date, lignocellulose, including cellulose, hemicellulose and lignin, has attracted extensive studies in facile photocatalytic valorisation. This review summarizes and analyzes the most recent research advances on photoreforming of lignocellulose to provide insights for future research, with a particular emphasis on the reformation of lignin because of its …

Comparative Static And Dynamic Analyses Of Solvents For Removal Of Asphaltene And Wax Deposits Above- And Below-Surface At An Iranian Carbonate Oil Field, Milad Norouzpour, Amin Azdarpour, Rafael M. Santos, Ali Esfandiarian, Moein Nabipour, Erfan Mohammadian, Abbas K. Manshad, Alireza Keshavarz

Research outputs 2022 to 2026

During production from oil wells, the deposition of asphaltene and wax at surface facilities and porous media is one of the major operational challenges. The crude oil production rate is significantly reduced due to asphaltene deposition inside the reservoir. In addition, the deposition of these solids inside the surface facilities is costly to oil companies. In this study, the efficiency of different solvents in dissolving asphaltene and wax was investigated through static and dynamic tests. The analysis of solid deposits from the surface choke of one of the Iranian carbonate oil fields showed that they consisted of 41.3 wt % …

Artifacts In Localised Multivariate Uniform Conditioning: A Case Study, Oscar Rondon, Hassan Talebi

Research outputs 2022 to 2026

Localised Multivariate Uniform Conditioning (LMUC) is a technique designed for spatially locating Selective Mining Unit (SMU) grades derived using Multivariate Uniform Conditioning (MUC) for the assessment of recoverable resources. LMUC has the advantage of producing SMU estimates conforming to the MUC panel-specific grade-tonnage curves while preserving the spatial grade distribution at the selective mining level. However, LMUC results have two severe artifacts. This paper documents both artifacts using four grades from a large nickel–cobalt laterite deposit in Western Australia.

Confined Tri-Functional Feox@Mno2@Sio2 Flask Micromotors For Long-Lasting Motion And Catalytic Reactions, Yangyang Yang, Lei Shi, Jingkai Lin, Panpan Zhang, Kunsheng Hu, Shuang Meng, Peng Zhou, Xiaoguang Duan, Hongqi Sun, Shaobin Wang

Research outputs 2022 to 2026

H2O₂-fueled micromotors are state-of-the-art mobile microreactors in environmental remediation. In this work, a magnetic FeO_x@MnO₂@SiO₂ micromotor with multi-functions is designed and demonstrated its catalytic performance in H₂O₂/peroxymonosulfate (PMS) activation for simultaneously sustained motion and organic degradation. Moreover, this work reveals the correlations between catalytic efficiency and motion behavior/mechanism. The inner magnetic FeO_x nanoellipsoids primarily trigger radical species (OH and O₂−) to attack organics via Fenton-like reactions. The coated MnO₂ layers on FeO_x surface are responsible for decomposing H₂O₂ into O_{2 …}

Natural Manganese Ores For Efficient Removal Of Organic Pollutants Via Catalytic Peroxymonosulfate-Based Advanced Oxidation Processes, Zhengxin Yao, Roufei Chen, Ning Han, Hongqi Sun, Ngie Hing Wong, Lusi Ernawati, Shaobin Wang, Jaka Sunarso, Shaomin Liu

Research outputs 2022 to 2026

Peroxymonosulfate-based advanced oxidation processes (PMS-AOPs) for in situ persistent organic pollutant (POP) remediation in aqueous solutions can be a promising technology. However, this technology is constrained by its high toxicity and cost of metal oxide and non-metal catalysts for PMS activation. Here, we investigated the catalytic performance of a widely available natural mineral, manganese ore (MO), for PMS activation. A series of natural MO samples in an aqueous solution were prepared via the Fenton-like reaction. The samples' crystalline structure, surface morphology, textural properties, and other surface characteristics of the selected MO were systematically characterized. The effects of PMS concentration and …

Role Of Air Staging In A Batch-Type Fixed Bed Biomass Combustor Under Constant Primary Air, Awais Junejo, Yasir M. Al-Abdeli, Jacobo Porteiro

Research outputs 2022 to 2026

Staged combustion of biomass is the most suitable thermo-chemical conversion for achieving lower gaseous emissions and higher fuel conversion rates. In a staged fixed bed combustion of biomass, combustion air is supplied in two stages. In the first stage, primary air is provided below the fuel, whereas in the later stage, secondary air is supplied in the freeboard region. The available literature on the effects of air staging (secondary air location) at a constant primary air flow rate on combustion characteristics in a batch-type fixed bed combustor is limited and hence warrants further investigations. This study resolves the effect of …

Splitting Tensile Strength Of Recycled Tire Steel Fiber-Reinforced Alkali-Activated Slag Concrete Designed By Taguchi Method, Milad Eskandarinia, Mina Esmailzade, Farhad Aslani

Research outputs 2022 to 2026

Despite offering several benefits in terms of environment and economics, few studies were conducted on the ground granulated blast furnace slag (GGBFS) based alkali-activated concrete reinforced with recycled tire steel fibers (RTSFs). Therefore, this paper employed the Taguchi method to investigate and optimize the influence of GGBFS content, the alkaline solution to GGBFS content ratio, sodium hydroxide solution concentration, and RTSF volume fraction on splitting tensile strength (STS) of recycled tire steel fiber-reinforced alkali-activated slag concrete (RTSFR-AASC). The microstructural evaluation was done through scanning electron microscopy, and Fourier transform infrared spectroscopy (FTIR) analyses. The results indicated that the fiber content, …

Metal-Organic Framework-Based Biosensing Platforms For The Sensitive Determination Of Trace Elements And Heavy Metals: A Comprehensive Review, Hessamaddin Sohrabi, Shahin Ghasemzadeh, Sama Shakib, Mir Reza Majidi, Amir Razmjou, Yeojoon Yoon, Alireza Khataee

Research outputs 2022 to 2026

Heavy metals in food and water sources are potentially harmful to humans. Determination of these pollutants is critical for improving safety. Effective recognition systems are a contemporary challenge; several novel technologies for the quick, easy, selective, and sensitive determination of these compounds are in demand. Metal-organic framework (MOF)-based sensors and biosensors have crucial applications in identifying these potentially harmful substances. Here, we review electrochemical and optical biosensors for in situ sensing that are sensitive and cost effective, with a simple protocol and wide linear range. Despite the abundance of articles in this field, we assessed and checked out various basic …

Conductive 3d Nano-Biohybrid Systems Based On Densified Carbon Nanotube Forests And Living Cells, Roya Bagheri, Alicia K. Ball, Masoud Kasraie, Aparna Chandra, Xinqian Chen, Ibrahim Miskioglu, Zhiying Shan, Parisa Pour Shahid Saeed Abadi

Michigan Tech Publications

Conductive biohybrid cell-material systems have applications in bioelectronics and biorobotics. To date, conductive scaffolds are limited to those with low electrical conductivity or 2D sheets. Here, 3D biohybrid conductive systems are developed using fibroblasts or cardiomyocytes integrated with carbon nanotube (CNT) forests that are densified due to interactions with a gelatin coating. CNT forest scaffolds with a height range of 120–240 µm and an average electrical conductivity of 0.6 S/cm are developed and shown to be cytocompatible as evidenced from greater than 89% viability measured by live-dead assay on both cells on day 1. The cells spread on top and …