Matching Items (20)
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- All Subjects: Water
- Creators: School of Sustainability
- Creators: Wutich, Amber
- Creators: Chemical Engineering Program
Description
As Arizona enters its fifteenth year of drought and Lake Mead hits historic lows, water management and policy planning will become increasingly important to ensure future water security in the Southwestern region of the United States. This thesis compares water demand trends and policies at the municipal level in Phoenix and Tucson, Arizona over the time period from 1980-2010. By analyzing gallons per capita per day (GPCD) trends for each city in the context of population growth, drought, and major state and local policies over the twenty year period, reasons for declines in per capita water demand were explored. Despite differences in their available water sources and political cultures, both the City of Phoenix and the City of Tucson have successfully reduced their per capita water consumption levels between 1980 and 2010. However, this study suggests that each city's measured success at reducing GPCD has been more a result of external events (supply augmentation, drought, and differing development trends) rather than conservation and demand reduction regulations adopted under the auspices of the Groundwater Management Act.
ContributorsSnyder, Rachel Claire (Author) / Larson, Kelli (Thesis director) / Hirt, Paul (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / School of Sustainability (Contributor) / School of Politics and Global Studies (Contributor)
Created2015-05
Description
I set out to better understand the issues, perceptions & solutions surrounding drought. The question that compelled my project was "What might be all the ways that we can improve the experience of conserving, reusing & educating on the topic of water." Through the process of design research I developed a system of products that improves the user experiences surrounding water. The result is IOW, an intelligent 3-product system that aims to make your water needs & wants smarter & less wasteful.
ContributorsShappee, Christian Kyle (Author) / Shin, Dosun (Thesis director) / McDermott, Lauren (Committee member) / Barrett, The Honors College (Contributor) / Herberger Institute for Design and the Arts (Contributor) / School of Sustainability (Contributor) / The Design School (Contributor)
Created2015-05
Description
The study examines cross-cultural perceptions of wastewater reuse from 282 participants from four global sites representing varied levels of socio-economic and political development from the Global North and Global South: Spain, New Zealand, Fiji, and Guatemala. The data comes from the Global Ethnohydrology Survey conducted by the School of Human Evolution and Social Change during the summer of 2013. The Global Ethnohydrology Study is a transdisciplinary multi-year research initiative that examines the range of variation in local ecological knowledge of water issues, also known as "ethnohydrology." Participants were asked about their willingness, level of disgust, and concern with using treated wastewater for various daily activities. Additionally, they were asked to draw schematic representations of how wastewater should be treated to become drinkable again. Using visual content analysis, the drawings were coded for a variety of treatment levels and specific treatment processes. Conclusions about the perceived health implications from wastewater reuse that can stem from drinking treated wastewater were made. The relationship between humans and wastewater is one that has many direct social and health impacts on communities at large. In reaction to global limitations of freshwater, wastewater serves as a valuable resource to tap into. This research examines the cross-cultural public health concerns about treated wastewater in order to draw conclusions that can aid in strategic implementation of advocacy and public education about wastewater reuse.
ContributorsPatel, Sarah Shakir (Author) / Wutich, Amber (Thesis director) / Rice, Jacelyn (Committee member) / Barrett, The Honors College (Contributor) / School of Politics and Global Studies (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2015-05
Description
In this research, construction of a model membrane system using Polyvinylidene Chloride-Co Acrylonitrile and Linde Type A zeolites is described. The systems aims to separate out flow through zeolite pores and flow through interfaces between zeolites and polymers through the use of pore filled and pore open zeolites. Permeation tests and salt rejection tests were performed, and the data analyzed to yield approximation of separated flow through zeolites and interfaces. This work concludes the more work is required to bring the model system into a functioning state. New polymer selections and new techniques to produce the membrane system are described for future work.
ContributorsShabilla, Andrew Daniel (Author) / Lind, Mary Laura (Thesis director) / Lin, Jerry (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor)
Created2014-05
Description
This thesis aims to evaluate how in classroom demonstrations compare to regular education techniques, and how student learning styles affect interest in science and engineering as future fields of study. Science education varies between classrooms, but usually is geared towards lecture and preparation for standardized exams without concern for student interest or enjoyment.5 To discover the effectiveness of demonstrations in these concerns, an in classroom demonstration with a water filtration experiment was accompanied by several modules and followed by a short survey. Hypotheses tested included that students would enjoy the demonstration more than a typical class session, and that of these students, those with more visual or tactile learning styles would identify with science or engineering as a possible major in college. The survey results affirmed the first hypothesis, but disproved the second hypothesis; thus illustrating that demonstrations are enjoyable, and beneficial for sparking or maintaining student interest in science across all types of students.
ContributorsPiper, Jessica Marie (Author) / Lind, Mary Laura (Thesis director) / Montoya-Gonzales, Roxanna (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / Chemical Engineering Program (Contributor)
Created2014-05
Description
The Science of Water Art project is a collaborative work that brings together professionals, community members, college students and children to think about the role that water plays in each of our lives. Using a sample of 4th grade classrooms in Maricopa County, over 3000 drawings of children's perception of water today and in the future were collected. The 9-11 year olds were asked to draw pictures of 1) how they saw water being used in their neighborhood today (T1), and 2) how they imagined water would be used in their neighborhood 100 years from now (T2). The artwork was collected and coded for nine different themes, including: vegetation, scarcity, pollution, commercial sources of water, existing technology, technology innovation, recreational use, domestic use, and natural sources of water. Statistically significant differences were found between boys and girls for vegetation, technology and domestic use themes. This project allows for a look into how climate change and water insecurity is viewed by younger generations and gives a voice to children so that they may share their outlooks on this vital resource.
ContributorsVins, Holly Elizabeth (Author) / Wutich, Amber (Thesis director) / Newland, Judy (Committee member) / Beresford, Melissa (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / School of Social Transformation (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2013-05
Description
In 2021, Palestine will have been under official Israeli occupation for 54 years. As conflict persists between the two populations, it is becoming increasingly difficult to imagine a peaceful resolution. As international legal bodies have failed to bring an end to the occupation, the Israeli government continues to carry out extensive violations of human rights against the Palestinians. One significant consequence of the occupation has been the Palestinians’ lack of access to safe and reliable water, a problem that is continuing to worsen as a result of climate change and years of over-utilization of shared, regional water resources. Since the occupation started, international organizations have not only affirmed the general human right to water but have overseen several peace agreements between Israel and Palestine that have included stipulations on water. Despite these measures, neither water access nor quality has improved and, over time, has worsened. This paper will look at why international law has failed to improve conditions for Palestinians and will outline the implications of the water crisis on a potential solution between Israel and Palestine.
ContributorsTimpany, Grace Louise (Author) / Haglund, LaDawn (Thesis director) / Rothenberg, Daniel (Committee member) / School of Politics and Global Studies (Contributor, Contributor, Contributor) / School of Sustainability (Contributor) / School of Social Transformation (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
The impact of physical/chemical properties of gray water on microbial inactivation in gray water using chlorine was investigated through creating artificial gray water in lab, varying specific components, and then measuring microbial inactivation. Gray water was made through taking autoclaved nanopure water, and increasing the concentration of surfacants, the turbidity, the concentration of organic content, and spiking E. coli grown in tryptic soy broth (TSB); chlorine was introduced using Clorox Disinfecting Bleach2. Bacteria was detected using tryptic soy agar (TSA), and E. coli was specifically detected using the selective media, brilliance. The log inactivation of bacteria detected using TSA was shown to be inversely related to the turbidity of the solution. Complete inactivation of E. coli concentrations between 104-105 CFU/100 ml in gray water with turbidities between 10-100 NTU, 0.1-0.5 mg/L of humic acid, and 0.1 ml of Dawn Ultra, was shown to occur, as detected by brilliance, at chlorine concentrations of 1-2 mg/L within 30 seconds. These result in concentration time (CT) values between 0.5-1 mg/L·min. Under the same gray water conditions, and an E. coli concentration of 104 CFU/100 ml and a chlorine concentration of 0.01 mg/L, complete inactivation was shown to occur in all trials within two minutes. These result in CT values ranging from 0.005 to 0.02. The turbidity and humic acid concentration were shown to be inversely related to the log inactivation and directly related to the CT value. This study shows that chlorination is a valid method of treatment of gray water for certain irrigation reuses.
ContributorsGreenberg, Samuel Gabe (Author) / Abbaszadegan, Morteza (Thesis director) / Schoepf, Jared (Committee member) / Alum, Absar (Committee member) / Chemical Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Two large sectors of water consumption within cities are: city owned irrigated landscape (such as parks) and household consumption. A related, third sector of consumption that has very little research behind it is shared landscapes in residential communities. Neighborhood communities, including those with formal Homeowner’s Associations and informal Neighborhood Associations, have common landscapes they are responsible for up-keeping and irrigating. 208 neighborhood communities exist within the City of Tempe. Each year the city provides $30,000 in grant funding to these 208 neighborhoods to implement water conservation projects. This thesis focuses on ten neighborhoods who had applied and were granted funding to implement a conservation project between the years 2011 and 2016. My findings showed that this program has not been effective in reducing water consumption, wither due to the lack of implementation or the small-scale of the projects. From my research and synthesis, I suggest a layer of accountability be added to the program to ensure projects are effective and participants are implementing their projects and that the program is effective overall. This study provides the City of Tempe with relevant and viable information to aid management of water consumption and conservation within neighborhoods.
ContributorsApillanes, Sierra Caitlyn (Author) / Larson, Kelli (Thesis director) / Bomar, Melissa (Committee member) / School of Sustainability (Contributor, Contributor) / School of Earth and Space Exploration (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
This honors thesis is focused on two separate catalysis projects conducted under the mentorship of Dr. Javier Pérez-Ramírez at ETH Zürich. The first project explored ethylene oxychlorination over supported europium oxychloride catalysts. The second project investigated alkyne semihydrogenation over nickel phosphide catalysts. This work is the subject of a publication of which I am a co-author, as cited below.
Project 1 Abstract: Ethylene Oxychlorination
The current two-step process for the industrial process of vinyl chloride production involves CuCl2 catalyzed ethylene oxychlorination to ethylene dichloride followed by thermal cracking of the latter to vinyl chloride. To date, no industrial application of a one-step process is available. To close this gap, this work evaluates a wide range of self-prepared supported CeO2 and EuOCl catalysts for one-step production of vinyl chloride from ethylene in a fixed-bed reactor at 623 773 K and 1 bar using feed ratios of C2H4:HCl:O2:Ar:He = 3:3 6:1.5 6:3:82 89.5. Among all studied systems, CeO2/ZrO2 and CeO2/Zeolite MS show the highest activity but suffer from severe combustion of ethylene, forming COx, while 20 wt.% EuOCl/γ-Al2O3 leads to the best vinyl chloride selectivity of 87% at 15.6% C2H4 conversion with complete suppression of CO2 formation and only 4% selectivity to CO conversion for over 100 h on stream. Characterization by XRD and EDX mapping reveals that much of the Eu is present in non-active phases such as Al2Eu or EuAl4, indicating that alternative synthesis methods could be employed to better utilize the metal. A linear relationship between conversion and metal loading is found for this catalyst, indicating that always part of the used Eu is available as EuOCl, while the rest forms inactive europium aluminate species. Zeolite-supported EuOCl slightly outperforms EuOCl/γ Al2O3 in terms of total yield, but is prone to significant coking and is unstable. Even though a lot of Eu seems locked in inactive species on EuOCl/γ Al2O3, these results indicate possible savings of nearly 16,000 USD per kg of catalyst compared to a bulk EuOCl catalyst. These very promising findings constitute a crucial step for process intensification of polyvinyl chloride production and exploring the potential of supported EuOCl catalysts in industrially-relevant reactions.
Project 2 Abstract: Alkyne Semihydrogenation
Despite strongly suffering from poor noble metal utilization and a highly toxic selectivity modifier (Pb), the archetypal catalyst applied for the three-phase alkyne semihydrogenation, the Pb-doped Pd/CaCO3 (Lindlar catalyst), is still being utilized at industrial level. Inspired by the very recent strategies involving the modification of Pd with p-block elements (i.e., S), this work extrapolates the concept by preparing crystalline metal phosphides with controlled stoichiometry. To develop an affordable and environmentally-friendly alternative to traditional hydrogenation catalysts, nickel, a metal belonging to the same group as Pd and capable of splitting molecular hydrogen has been selected. Herein, a simple two-step synthesis procedure involving nontoxic precursors was used to synthesize bulk nickel phosphides with different stoichiometries (Ni2P, Ni5P4, and Ni12P5) by controlling the P:Ni ratios. To uncover structural and surface features, this catalyst family is characterized with an array of methods including X-ray diffraction (XRD), 31P magic-angle nuclear magnetic resonance (MAS-NMR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Bulk-sensitive techniques prove the successful preparation of pure phases while XPS analysis unravels the facile passivation occurring at the NixPy surface that persists even after reductive treatment. To assess the characteristic surface fingerprints of these materials, Ar sputtering was carried out at different penetration depths, reveling the presence of Ni+ and P-species. Continuous-flow three-phase hydrogenations of short-chain acetylenic compounds display that the oxidized layer covering the surface is reduced under reaction conditions, as evidenced by the induction period before reaching the steady state performance. To assess the impact of the phosphidation treatment on catalytic performance, the catalysts were benchmarked against a commercial Ni/SiO2-Al2O3 sample. While Ni/SiO2-Al2O3 presents very low selectivity to the alkene (the selectivity is about 10% at full conversion) attributed to the well-known tendency of naked nickel nanoparticles to form hydrides, the performance of nickel phosphides is highly selective and independent of P:Ni ratio. In line with previous findings on PdxS, kinetic tests indicate the occurrence of a dual-site mechanism where the alkyne and hydrogen do not compete for the same site.
This work is the subject of a publication of which I am a co-author, as cited below.
D. Albani; K. Karajovic; B. Tata; Q. Li; S. Mitchell; N. López; J. Pérez-Ramírez. Ensemble Design in Nickel Phosphide Catalysts for Alkyne Semi-Hydrogenation. ChemCatChem 2019. doi.org/10.1002/cctc.201801430
Project 1 Abstract: Ethylene Oxychlorination
The current two-step process for the industrial process of vinyl chloride production involves CuCl2 catalyzed ethylene oxychlorination to ethylene dichloride followed by thermal cracking of the latter to vinyl chloride. To date, no industrial application of a one-step process is available. To close this gap, this work evaluates a wide range of self-prepared supported CeO2 and EuOCl catalysts for one-step production of vinyl chloride from ethylene in a fixed-bed reactor at 623 773 K and 1 bar using feed ratios of C2H4:HCl:O2:Ar:He = 3:3 6:1.5 6:3:82 89.5. Among all studied systems, CeO2/ZrO2 and CeO2/Zeolite MS show the highest activity but suffer from severe combustion of ethylene, forming COx, while 20 wt.% EuOCl/γ-Al2O3 leads to the best vinyl chloride selectivity of 87% at 15.6% C2H4 conversion with complete suppression of CO2 formation and only 4% selectivity to CO conversion for over 100 h on stream. Characterization by XRD and EDX mapping reveals that much of the Eu is present in non-active phases such as Al2Eu or EuAl4, indicating that alternative synthesis methods could be employed to better utilize the metal. A linear relationship between conversion and metal loading is found for this catalyst, indicating that always part of the used Eu is available as EuOCl, while the rest forms inactive europium aluminate species. Zeolite-supported EuOCl slightly outperforms EuOCl/γ Al2O3 in terms of total yield, but is prone to significant coking and is unstable. Even though a lot of Eu seems locked in inactive species on EuOCl/γ Al2O3, these results indicate possible savings of nearly 16,000 USD per kg of catalyst compared to a bulk EuOCl catalyst. These very promising findings constitute a crucial step for process intensification of polyvinyl chloride production and exploring the potential of supported EuOCl catalysts in industrially-relevant reactions.
Project 2 Abstract: Alkyne Semihydrogenation
Despite strongly suffering from poor noble metal utilization and a highly toxic selectivity modifier (Pb), the archetypal catalyst applied for the three-phase alkyne semihydrogenation, the Pb-doped Pd/CaCO3 (Lindlar catalyst), is still being utilized at industrial level. Inspired by the very recent strategies involving the modification of Pd with p-block elements (i.e., S), this work extrapolates the concept by preparing crystalline metal phosphides with controlled stoichiometry. To develop an affordable and environmentally-friendly alternative to traditional hydrogenation catalysts, nickel, a metal belonging to the same group as Pd and capable of splitting molecular hydrogen has been selected. Herein, a simple two-step synthesis procedure involving nontoxic precursors was used to synthesize bulk nickel phosphides with different stoichiometries (Ni2P, Ni5P4, and Ni12P5) by controlling the P:Ni ratios. To uncover structural and surface features, this catalyst family is characterized with an array of methods including X-ray diffraction (XRD), 31P magic-angle nuclear magnetic resonance (MAS-NMR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Bulk-sensitive techniques prove the successful preparation of pure phases while XPS analysis unravels the facile passivation occurring at the NixPy surface that persists even after reductive treatment. To assess the characteristic surface fingerprints of these materials, Ar sputtering was carried out at different penetration depths, reveling the presence of Ni+ and P-species. Continuous-flow three-phase hydrogenations of short-chain acetylenic compounds display that the oxidized layer covering the surface is reduced under reaction conditions, as evidenced by the induction period before reaching the steady state performance. To assess the impact of the phosphidation treatment on catalytic performance, the catalysts were benchmarked against a commercial Ni/SiO2-Al2O3 sample. While Ni/SiO2-Al2O3 presents very low selectivity to the alkene (the selectivity is about 10% at full conversion) attributed to the well-known tendency of naked nickel nanoparticles to form hydrides, the performance of nickel phosphides is highly selective and independent of P:Ni ratio. In line with previous findings on PdxS, kinetic tests indicate the occurrence of a dual-site mechanism where the alkyne and hydrogen do not compete for the same site.
This work is the subject of a publication of which I am a co-author, as cited below.
D. Albani; K. Karajovic; B. Tata; Q. Li; S. Mitchell; N. López; J. Pérez-Ramírez. Ensemble Design in Nickel Phosphide Catalysts for Alkyne Semi-Hydrogenation. ChemCatChem 2019. doi.org/10.1002/cctc.201801430
ContributorsTata, Bharath (Author) / Deng, Shuguang (Thesis director) / Muhich, Christopher (Committee member) / Chemical Engineering Program (Contributor, Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05