Membrane Science Commons^™

Statistical Investigation Of Gypsum Crystallization Kinetics, Azmain A. Akash

LSU Master's Theses

Gypsum, a naturally occurring mineral salt, is frequently encountered in industrial processes such as seawater desalination and power plant cooling. Over the years, significant effort has been devoted to controlling the crystallization of gypsum through various chemical approaches, including acidification, chelating agents, and antiscalant polymers. Nevertheless, the cost associated with chemical treatments may be reduced by incorporating physical operational strategies to complement chemical methods in regulating gypsum crystallization.

This study systematically examines the comparative roles of chemical and physical entropy in the gypsum crystallization process to elucidate their respective influences on gypsum growth kinetics. Chemical entropy is manipulated by adjusting …

Membrane Reactor Modeling And Optimization For Hydrogen Production, Ayooluwa Tomiwa Akintola

Graduate Theses, Dissertations, and Problem Reports (ETD)

There has been an ongoing trend toward cleaner fuels for more environmentally benign forms of energy generation. Recently, hydrogen has been identified as a clean fuel for energy generation. However, the most established, efficient, and widely utilized technique for producing hydrogen remains the steam methane reforming (SMR) in the presence of catalyst. Unlike other fossil fuels, utilizing methane from natural gas in an SMR process to produce hydrogen emits less, but yet a notable sum of carbon dioxide. Furthermore, the endothermic nature of SMR reactions imply that there is a high energy requirement to obtain a substantial amount of hydrogen …

The Optimization And Manufacturing Scale-Up Of Polymeric Membranes Using Eco-Friendly Solvents, David Lu

Theses and Dissertations--Chemical and Materials Engineering

Polymeric membranes have become a prominent technology applied in water filtration due to the lower cost, energy input, and simpler manufacturing process relative to other separation technologies. However, the environmental impact of polymeric membrane fabrication remains a hindrance due to the use of hazardous solvents derived from fossil fuels (e.g., DMAc, NMP, DMF) that pose a risk to the environment and human health. Whereas recent studies have demonstrated the proof-of-concept of polymeric membrane derived from eco-friendly solvents, the next steps of optimizing and upscaling the production of these membranes remains understudied and a gap between lab-scale studies and the path …

Synthesis Of Activated Carbon From Coconut Shell And Recycled Styrofoam Nanofiber For Water Filtration, Rahma Dani, Ismet Ismet, Leni Marlina, Rona Alisya, Muhamad Abel Kirana Aldi, Anggi Ludiansyah, Lintang Auliya Kurdiati, Meutia Kamilatun Nuha Ap Idjan, Agung Mataram, Muhammad Rama Almafie, Ida Sriyanti

Makara Journal of Science

Water pollution affects life sustainability; hence, several efforts have been exerted to overcome this problem. For ex-ample, nanofiber membrane technology is introduced to retain solutes while allowing only water molecules to pass through the system. Therefore, this study aimed to maximize the technology for water filtration using the electrospin-ning method by combining Styrofoam waste-based polymer with activated carbon from coconut shell waste (ACCS). The nanofiber diameter produced ranged from 590 nm to 610 nm with porous characteristics and without beads. The carbon content varied from 68.04% to 69.84%, according to the energy dispersive X-ray measurement, demonstrating the composite’s effectiveness. The …

Synthesis, Characterization And Testing Of Graphene-Based Materials For Proton-Exchange Membrane Fuel Cell Catalysts, Hassan Shirzadi Jahromi

Dissertations

The requirement for low cost and efficient catalysts for fuel cells motivated the proposed research on Nitrogen-doped reduced graphene oxide (N-rGO) integrated with transition metal zeolitic imidazolate frameworks (ZIFs). Synthesis, characterization and performance evaluation of the newly synthesized nitrogen-doped graphene oxide-based catalysts for Proton Exchange Membrane Fuel Cells (PEMFCs) constitutes the main objective of this thesis.

The synthesis of N-rGO combined with cobalt, nickel, or iron ZIFs was carried out using wet chemical methods followed by one step pyrolysis at 900°C, resulting in catalysts with highly porous structures and uniform metal nanoparticle distribution. These were characterized for structure, microstructure, composition …

Electrified Membrane For Water Treatment And Resource Recovery: Advancing Multiscale Strategies In Gas-Involving Reactions, Jianan Gao

Dissertations

Multifunctional, modular, and scalable water treatment technologies that operate without chemical additives are crucial for addressing global water pollution challenges. While traditional membrane-based separation processes are crucial for ensuring clean water supplies, they primarily focus on pollutant removal rather than on the upcycling of pollutants into valuable resources. Electrified membrane filtration presents a robust alternative, utilizing minimal or no chemical additives and harnessing electrical power to directly reduce contaminants or produce reactive oxidants or reductants on-site.

This dissertation is dedicated to the development of innovative electrochemically reactive membranes designed to address three major challenges: (1) the engineering of electrocatalysts with …

Voltammetric Determination Of Hydrogen Peroxide At Decorated Palladium Nanoparticles/Poly 1,5- Diaminonaphthalene Modified Carbon-Paste Electrode, Ziad Khalifa, Mohamed Fathi Abo Oura, Magdi Abdelazzem, Ablah Hathoot

Chemical Engineering

In this work, palladium nanoparticles (PdNPs)/p1,5-DAN/ carbon paste electrode (CPE) and p1,5-DAN/CPE sensors have been developed for determination of hydrogen peroxide. Both sensors showed a highly sensitive and selective electrochemical behaviour, which were derived from a large specific area of poly 1,5 DAN and super excellent electroconductibility of PdNPs. PdNPs/p1,5-DAN/CPE exhibited excellent performance over p1,5-DAN/CPE. Thus, it was used for detecting hydrogen peroxide (H2O2) with linear ranges of 0.1 to 250 μM and 0.2 to 300 μM as well as detection limits (S/N= 3) of 1.0 and 5.0 nM for square wave voltammetry (SWV) and cyclic voltammetry (C.V) techniques, respectively. …

Synthesis Of Uv-Blocking Titanium Oxide Films Via Remote-Type Atmospheric Pressure Plasma Cvd, Hayate Endo, Akira Shirakura, Shinya Kudo, Tetsuya Suzuki

Journal of Applied Packaging Research

This study aims to enhance UV resistance in plastics, focusing on polycarbonate (PC) and polypropylene (PP) commonly used in reuseable packaging. Traditional organic UV absorbers face safety and cost challenges, prompting our investigation into alternative methods. We utilized chemical vapor deposition (CVD), specifically Atmospheric Pressure Plasma Enhanced CVD (AP-PE-CVD), to apply titanium oxide (TiO₂) thin films. This innovative approach, using a remote-type AP-PE-CVD technique, enables coating on complex surfaces and 3D objects. The produced TiO2 films, containing over 20% titanium, showed a UV transmittance of 14.5% at 310 nm and effective UV blocking starting at 372 nm. The …

Carboxen Micropreconcentrator Performance For Analyzing Btex In Air., Raymond Daniel Spargo

Electronic Theses and Dissertations

Volatile Organic Compounds (VOCs) are a class of toxic chemicals in environmental air associated with several serious health risks. Some of the most common and concerning VOCs are Benzene, Toluene, Ethyl Benzene, and Xylene (BTEX). To maintain healthy air quality in these environments, researchers pursue instruments and processes to quickly and accurately predict sub-ppb concentrations of BTEX in indoor and outdoor air. By employing a micropreconcentrator (μPC) to combine Solid-Phase Micro-Extraction (SPME) with Gas Chromatography Mass Spectrometry (GC-MS) analysis, trace BTEX content in air samples can be captured, extracted and analyzed. In this thesis, a dual-compartment μPC with Carboxen 1000 …

Frameworks For The Techno-Economic Assessment Of Membrane-Based Bioprocessing Platforms, Juan Jose Romero Conde

All Dissertations

This dissertation describes developing and implementing computational frameworks for simulating and optimizing purification processes in the biopharmaceutical industry. The framework performs techno-economic analyses to establish value propositions for new process alternatives, especially membrane technologies. Initially, the focus is developing a framework capable of simulating monoclonal antibody (mAb) capture using membrane and resin media in multi-column chromatography (MCC) platforms for continuous manufacturing. Subsequently, the impact of capture MCC is compared against other intensification strategies in established mAb manufacturing facilities. Finally, the framework application expands to simulate the purification of adeno-associated virus (AAV) vectors for gene therapy.

Chapter 2 details the framework …

Elucidating The Impact Of Casting Solvent On Vanadium Ion Transport In Solution-Cast Ionomer Biocomposites Containing Lignin, Zhongyu Wang

All Theses

This paper attempts to investigate the influence of solvent choice to the Nafion-lignin proton exchange membranes that used in the vanadium redox flow batteries. The influence of two different solvents: DMF and DMSO were investigated in this paper. Results show that when using DMSO as solvent, Nafion-lignin membranes' vanadium ion cross over can be greatly reduced in comparing with membranes prepared from DMF. Also, membranes prepared from DMSO also show higher water uptake ability and lower ion exchange capacity than the membranes prepared from DMF. This paper has also investigated the influence of lignin type to the membranes. Results show …

Sulfonated Lignin-Based Ionomer Biocomposite Membranes For Redox Flow Batteries, Aiswarya Mechoor

All Theses

The current benchmark membrane for vanadium redox flow batteries (VRFBs), Nafion™, accounts for up to 40% of the cost of the battery and suffers from poor ion selectivity, leading to diminished battery performance. Consequently, alternative ionomer membranes, such as sulfonated poly(ether ether ketone) (SPEEK), have recently garnered attention due to their lower cost and similar performance properties to Nafion. However, like Nafion, SPEEK also suffers from poor ion selectivity. In this study, we attempt to address the issue of poor ion selectivity by developing SPEEK–lignin composite membranes containing fractionated and functionalized lignin. Specifically, two lignin fractions – a low molecular …

Sulfonated Ionomer Composite Membranes For Use In Vanadium Redox Flow Batteries, Xueting Wang

All Dissertations

While vanadium redox flow batteries (VRFBs) have garnered significant attention as a promising scalable energy storage technology, the current membrane material used in this technology, Nafion™, suffers from high cross mixing of vanadium ions in the liquid electrolytes, directly impacting battery performance properties such as the voltage and coulombic efficiencies, as well as resulting in a reduction in the overall battery lifetime. The use of ionomer nancomposites has proven to be one promising route of directly addressing the issue of high ion crossover, though the mechanism by which the nanoparticles act to reduce crossover remains in open question. Herein, the …

Exploring The Morphological Surface Resistance And Optical Absorption Of Thin Black Carbon Nanotube Films For Electronic And Optoelectronic Devices, Ziad Khalifa, Sameh Osama Abdellatif

Chemical Engineering

This study investigates the optical and electrical properties of thin black films of carbon nanotubes (CNTs) fabricated under various conditions to explore their potential integration as either a perfect broadband absorber or enhanced counter electrode. The study involves SEM measurements, surface resistance measurements, and UV–Vis. spectrometer analysis. The results show that the CNT thin films exhibit high electrical conductivity and strong light absorption across various wavelengths. Optically, we investigated the impact of varying the growth temperature and catalyst temperature on the absorption profile of the thin films. The fabricated and deposited CNTs showed broadband absorption spectra, reaching 92.8% of the …

Process Simulation For Converting Co2 Emissions From The Cementindustry To Dimethyl Ether, Nour Abou Seada, Dina Aboelela

Biochemical Engineering

Climate change is the leading severe problem in the twenty-first century, which is associated with greenhouse gas emissions,carbon dioxide that is the foremost cause of global warming and super greenhouse effect. In this concern, to avoid hazardousproblems, the steady stream of CO2 effluents existing in the atmosphere must be transformed to beneficial products for beingused as an abundant chemical feedstock. Implementing a new green strategy, which is known for the catalytic hydrogenationof CO2 into alternative fuels and valuable chemicals, will be a long-lasting solution to alleviate CO2 emissions. In this paper,a process simulation showing the synthesis of dimethyl ether (DME) …

Hydrogen Production From Microbial Electrolysis Cells Powered With Microbial Fuel Cells, Dina Aboelela

Biochemical Engineering

No abstract provided.

Synthesis, Characterization, And Performance Assessment Of Reusable And Biodegradable Antimicrobial Polymeric Membranes For Aerosolized Pathogen Inactivation And Filtration, Ebuka Ogbuoji

Theses and Dissertations--Chemical and Materials Engineering

Air filtration technology has proven effective in purifying air by trapping particulates which can cause adverse health effects. High Efficiency Particulate Air (HEPA) filters, capable of capturing over 99.99% of PM_0.3, are recommended for critical applications. However, conventional non-woven HEPA filters rely on electrostatic interactions to trap smaller particles, which can deplete over time or after cleaning, reducing filtration efficiency and posing health risks. Additionally, these filters contribute to plastic waste.

This dissertation investigated the feasibility of using flat sheet polymeric membranes fabricated via nonsolvent-induced phase separation (NIPS) as reusable and biodegradable alternatives to commercially available non-biodegradable air …

Application Of Predictive Control Strategies For Water-Gas Shift Membrane Reactors Using Data-Driven Models, Bernardo De Oliveira Vecchio

Graduate Theses, Dissertations, and Problem Reports (ETD)

As demand for more efficient processes keeps rising and more restrictive environmental legislation requires higher levels of both yield and purity, the process industry has now, more than ever, been looking for new ways to achieve these goals. One approach has been the implementation of Process Intensification (PI). PI aims to combine multiple unit operations into a single one, promoting efficiency gains on multiple levels. This combination, however, leads to complex process dynamics, and controlling such processes, particularly when setup as multi-input-multi-output (MIMO) systems, presents a great challenge due to highly interactive complex process dynamics and the imposition of many …

Design And Implementation Of Portable Power And Desalination Units Powered By Renewable Energy, Mo'ath A. Massad

Mechanical Engineering Theses

Freshwater scarcity is a critical global issue, especially in remote areas or areas impacted by natural disasters. Water desalination is one of the most effective methods to provide fresh water where it is needed. However, large-scale desalination plants cannot provide fresh water in the case of a natural disaster far from the plant's location. To address this, portable desalination units powered by renewable energy sources can be developed to supply potable water and power as a by-product for emergency situations. This work explored the application of different desalination methods, including reverse osmosis (RO) and electrodialysis (ED), in conjunction with renewable …

Functionalized Microfiltration Membranes For Aerosol Capture To Chloro-Organic Degradation, Rollie George Mills

Theses and Dissertations--Chemical and Materials Engineering

The environmental remediation of water and air sources is a challenging field, due to widespread contamination, pollutant variety, and efficiency of existing treatment options. Remediation of certain pollutants, such as per- and polyfluorinated chemicals (PFAS), polychlorinated biphenyls (PCBs), volatile organic compounds (VOCs), and viral aerosols, has shown promise via adsorptive, degradative, or filtration-based processes, each with their respective advantages and limitations. Membrane technology is one option that has exhibited considerable pollutant removal from environmental sources via reverse osmosis (RO) filtration, but is limited by low permeabilities and lack of pollutant detoxification. With the support of NIEHS and NSF, the functionalization …