Matching Items (36)
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- All Subjects: Sustainability
- All Subjects: Health
- Creators: Chemical Engineering Program
- Member of: Barrett, The Honors College Thesis/Creative Project Collection
- Status: Published
Description
Given their manufacturing versatility, plastics have fundamentally changed commercial consumerism. Unfortunately, two of the largest drawbacks to current plastics on the market is their dependency on fossil fuels and their lack of circular recyclability. In this paper, the focus will be on the latter issue. Circular recyclability can be described as the idea of minimizing waste through its reformation back into a commodity. Currently, the primary method of recycling plastics, mechanical recycling, can only be achieved through melting and reshaping plastic for reuse. A significant drawback to this method is the reduction in chain molecular weight and subsequent loss of mechanical integrity through multiple reheating cycles. Chemical recycling provides an alternative where the polymer is broken down through chemically reactive sites, allowing the material to be recycled a theoretically infinite number of times and maintain its mechanical properties.
Polyethylene, one of the largest classes of industrially produced plastic, does not have any commercially relevant chemically recyclable derivatives. The structure of polyethylene is primarily composed of long, nonpolar hydrocarbon chains that provide the material’s signature tough property. To make a material that can be depolymerizable for chemical recycling, polar ester functional groups must be added throughout the chain, allowing for chain scission by hydrolysis. Unfortunately, while the incorporation of ester functionality into polyethylene has been studied previously, material strength decreases as a result of this modification, sacrificing the integrity of the final product.
Herein, I propose the incorporation of nucleobase pairings into the ester-containing polyethylene, which will add supramolecular hydrogen bonding reinforcements to improve the mechanical performance while maintaining chemical recyclability. This addition to the polyethylene backbone will be achieved by the synthesis of a ureido cytosine (UCy) diol, which contains 4 complementary hydrogen bonding sites for enhanced intermolecular forces between polyethylene chains.
ContributorsChase, Timothy (Author) / Long, Timothy (Thesis director) / Barker, Charlotte (Committee member) / Barrett, The Honors College (Contributor) / Industrial, Systems & Operations Engineering Prgm (Contributor) / Chemical Engineering Program (Contributor) / School of Public Affairs (Contributor)
Created2024-05
Description
This honors thesis report aims to propose a sustainable long-term solution for providing off-grid solar energy to rural communities that lack the necessary grid energy infrastructure. With this in mind, we aim to establish the framework and documentation for people to be able to build and maintain their own off-grid solar power systems. Due to recent pushes for clean energy both nationwide and statewide, the team will discuss the current renewable energy market and the incentives to justify the future growth potential of residential solar energy systems, which includes off-grid or remote solar. This discussion will include comparing pre-built solar systems currently offered for purchase against the proposed design outlined in this report. Notably, the outlined design has been made with an emphasis on system sustainability, low initial cost, reliability, ease of manufacturing/maintenance, and material selection. Lastly, the team will discuss the project’s approach to documentation with a user manual draft to ensure the system's long-term sustainability and troubleshooting. Although the efforts of this project have increased over time, this project remains active within the ASU EWB chapter, meaning that not all aspects described throughout this report are fully complete.
The Native American community of Shonto, Arizona, will be used as an example to understand a rural community's needs for designing a solar panel system that provides sufficient energy for a single household. The project was completed in collaboration with Arizona State University’s Engineering Projects In Community Service (EPICS) program and Engineers Without Borders (EWB) chapter. Both these organizations aim to connect ASU students to the professional mentors and resources they need to design and implement low-cost, small-scale, easily replicated, and sustainable engineering projects.
ContributorsHaq, Emmen (Author) / Sosa, Jorge (Co-author) / Beltran, Salvador (Thesis director) / Pham, Brandon (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor)
Created2024-05
Description
The possibility of creating inorganic/organic hybrid materials has yet to be fully explored within geopolymer research. Using PDMS as an organic precursor, the surface of sodium and potassium geopolymers of varying precursor composition were functionalized with degraded PDMS oligomers. Both types of geopolymer yielded hydrophobic materials with BET surface area of 0.6475 m2/g and 4.342 m2/g for sodium and potassium geopolymer, respectively. Each respective material also had an oil capacity of 74.75 ± 4.06 weight% and 134.19 ± 4.89 weight%. X-ray diffraction analysis demonstrated that the PDMS functionalized sodium geopolymers had similar crystal structures that matched references for zeolite A and sodalite. The potassium geopolymers were amorphous, but showed consistency in diffraction patterns across different compositions.
ContributorsMaurer, Matthew (Author) / Seo, Don (Thesis director) / Ciota, David (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor)
Created2022-05
Description
Plastic consumption has reached astronomical amounts. The issue is the single-use plastics that continue to harm the environment, degrading into microplastics that find their way into our environment. Finding sustainable, reliable, and safe methods to break down plastics is a complex but valuable endeavor. This research aims to assess the viability of using biochar as a catalyst to break down polyethylene terephthalate (PET) plastics under hydrothermal liquefaction conditions. PET is most commonly found in single-use plastic water bottles. Using glycolysis as the reaction, biochar is added and assessed based on yield and time duration of the reaction. This research suggests that temperatures of 300℃ and relatively short experimental times were enough to see the complete conversion of PET through glycolysis. Further research is necessary to determine the effectiveness of biochar as a catalyst and the potential of process industrialization to begin reducing plastic overflow.
ContributorsWyatt, Olivia (Author) / Deng, Shuguang (Thesis director) / Jin, Kailong (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor)
Created2023-05
Description
The United Nations identified global warming and climate change as the biggest challenge in modern human development. The reduction in the use of petroleum and oil will be a necessary step in the advancement for every industry using petroleum products. The engineered Escherichia coli strain M0158 produces malate, a food additive and cosmetic chemical. The bioreactor in this study uses carbon dioxide (CO2) delivered through hollow-fiber membranes (HFMs) to dissolve the gas efficiently into the growth solution, eliminating the conventional need for direct bicarbonate supplementation. The current mass balance assumes 100% of the CO2 into the solution was being fixed to the product and standing in the growth solution, or there was no CO2 moving out of the system without being utilized. A system of iterative experimentation was set up to measure the CO2 concentration and flow rate in the outlet gas. In the first iteration of the design, an Arduino microcontroller, a SprintIR-6S-5 CO2 sensor, and a flow rate sensor were used to measure these values at the outlet gas stream. Through the experimentation, the design removed the flow rate sensor at the outlet and added an argon sweep gas controlled with a mass flow controller (MFC). The sensor setup was assessed for its reliability and consistency over a 24-hour long experiment to understand if it could function continuously throughout a 6-day fermentation experiment. Then, characterization curves quantify the amount of CO2 that leaves the system without bacterial consumption and these curves were measured for 8, 10, and 12 HFMs in an abiotic system. Lastly, a bioreactor with active cells was fit with the sensor system and measured for 3 days continuously with 10 HFMs. The results of this final experiment begin to show the consumption rates of the bacteria and quantify the CO2 lost from the system. With this data and further experimentation with other HFM setups and bacteria, the loss of CO2 in membrane bioreactor systems can be quantified and the overall sustainability can be measured.
ContributorsFisher, Bennett (Author) / Nielsen, David (Thesis director) / Machas, Michael (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor) / Dean, W.P. Carey School of Business (Contributor)
Created2024-05
Description
The clock is ticking for the global community to attain the United Nations' Sustainable Development Goals (SDGs) by 2030, underscoring the urgent need for enhanced efforts to address the interconnected challenges outlined in the seventeen comprehensive SDGs.
In this context, philanthropy emerges as a critical driver of positive change, playing a pivotal role in advancing social change and sustainable development. Partnered philanthropy, a rising trend within the philanthropic sector characterized by collaborative approaches to grantmaking, is a promising approach to achieving the SDGs.
This study examines the effectiveness, challenges, and opportunities associated with partnered philanthropy in attaining the SDGs. By analyzing current practices and outcomes, the study offers actionable recommendations for leveraging partnered philanthropy to accelerate progress toward a sustainable and equitable future.
Building upon the proposed actions and acknowledging the challenges, one key recommendation outlined in this study is the importance of implementing a framework to guide collaborative philanthropic efforts in this space more effectively. Tracking the progress of the SDGs is a highly data-driven process, relying on extensive statistics and evidence to paint a comprehensive picture, enabling the global community to understand how far they still need to go. While extensive targets and data exist for private sector entities pursuing the SDGs, the philanthropic sector lacks a comparable framework for tracking progress, highlighting the need for a more structured approach.
This study focuses on the role of partnered philanthropy in advancing SDGs 6 and 7, revealing critical insights into the evolving landscape of sustainable development initiatives. These findings offer guidance for concerned stakeholders and serve as a roadmap for accelerating progress toward a more sustainable future.
ContributorsCreek, Bryn (Author) / Boyer, Mackenzie (Thesis director) / Govani, Michelle (Committee member) / Obenauer, Monro (Committee member) / Barrett, The Honors College (Contributor) / Watts College of Public Service & Community Solut (Contributor) / Civil, Environmental and Sustainable Eng Program (Contributor)
Created2024-05