Barrett, The Honors College Thesis/Creative Project Collection

Much of Nepal lacks access to clean drinking water, and many water sources are contaminated with arsenic at concentrations above both World Health Organization and local Nepalese guidelines. While many water treatment technologies exist, it is necessary to identify those that are easily implementable in developing areas. One simple treatment that has gained popularity is biochar—a porous, carbon-based substance produced through pyrolysis of biomass in an oxygen-free environment. Arizona State University’s Engineering Projects in Community Service (EPICS) has partnered with communities in Nepal in an attempt to increase biochar production in the area, as it has several valuable applications including water treatment. Biochar’s arsenic adsorption capability will be investigated in this project with the goal of using the biochar that Nepalese communities produce to remove water contaminants. It has been found in scientific literature that biochar is effective in removing heavy metal contaminants from water with the addition of iron through surface activation. Thus, the specific goal of this research was to compare the arsenic adsorption disparity between raw biochar and iron-impregnated biochar. It was hypothesized that after numerous bed volumes pass through a water treatment column, iron from the source water will accumulate on the surface of raw biochar, mimicking the intentionally iron-impregnated biochar and further increasing contaminant uptake. It is thus an additional goal of this project to compare biochar loaded with iron through an iron-spiked water column and biochar impregnated with iron through surface oxidation. For this investigation, the biochar was crushed and sieved to a size between 90 and 100 micrometers. Two samples were prepared: raw biochar and oxidized biochar. The oxidized biochar was impregnated with iron through surface oxidation with potassium permanganate and iron loading. Then, X-ray fluorescence was used to compare the composition of the oxidized biochar with its raw counterpart, indicating approximately 0.5% iron in the raw and 1% iron in the oxidized biochar. The biochar samples were then added to batches of arsenic-spiked water at iron to arsenic concentration ratios of 20 mg/L:1 mg/L and 50 mg/L:1 mg/L to determine adsorption efficiency. Inductively coupled plasma mass spectrometry (ICP-MS) analysis indicated an 86% removal of arsenic using a 50:1 ratio of iron to arsenic (1.25 g biochar required in 40 mL solution), and 75% removal with a 20:1 ratio (0.5 g biochar required in 40 mL solution). Additional samples were then inserted into a column process apparatus for further adsorption analysis. Again, ICP-MS analysis was performed and the results showed that while both raw and treated biochars were capable of adsorbing arsenic, they were exhausted after less than 70 bed volumes (234 mL), with raw biochar lasting 60 bed volumes (201 mL) and oxidized about 70 bed volumes (234 mL). Further research should be conducted to investigate more affordable and less laboratory-intensive processes to prepare biochar for water treatment.

The Sonoran Desert in the Southwest region of the United States and the Northwest corner of Mexico is defined by low precipitation rates that are episodal, oscillating between years of higher yields than average and then below average levels. Water is essential for life and in the region, the lack of water proves an obstacle for people that must be faced to live and thrive there. Yet, millions of people live in this desert region and more people are moving currently. As current water resources are straining not only under increasing population but also with higher frequency and lengths of droughts in the region, water is becoming an important topic for future plans in the Sonoran Desert. However, a vast array of plants and animals have lived under these conditions by adapting to the low precipitation rates. By looking at the common flora and fauna of the region, humans may learn how to better live in the Sonoran Desert through biomimicry, the imitation of life. The natural design and processes of life in the Sonoran Desert can be studied to find ways to conserve, store and collect water for human consumption ensuring longevity within the region and beyond as water insecurity increases globally.

3D printing prosthetics for amputees is an innovative opportunity to provide a lower cost and customized alternative to current technologies. Companies, such as E-NABLE and YouBionic are developing myoelectric prosthetics, electrically powered terminal devices activated by electromyography (EMG), for transradial amputees. Prosthetics that are 3D printed are less expensive for juvenile use, more sustainable, and more accessible for those without insurance. Although they are typically not outfitted with the same complex grip patterns or durability of a traditional myoelectric prosthetic, they offer a sufficient durability (withstanding up to 150 N on average) and allow for new opportunities in prosthetic development. Devils Prosthetics, a student research and development group associated with Engineering Projects in Community Service (EPICS), has investigated the benefits and pitfalls of utilizing polyethylene terephthalate glycol (PETG) for 3D printing prosthetics as well as combining a MyoWare EMG sensor with machine learning for optimal control of the prosthetic.

The EPICS program, an acronym for Engineering Projects in Community Service, provides students an opportunity to create engineering solutions to “real world” problems. This honors thesis project is a collaboration with the EPICS program, the Vietnam Smart Agriculture EPICS team, and the Da Nang University of Technology (DUT) in Da Nang, Vietnam. The goal of the Vietnam Smart Agriculture EPICS team is to design an accessible system to reduce water consumption for Vietnamese small farmers through the use of smart agriculture technology. In January of 2023, my EPICS team and I were able to travel and interview five farmers in the Tra Que Farm to complete a needs assessment. The focus of this thesis project is to provide background research and to complete a feasibility study to aid the Vietnam Smart Agriculture EPICS team in developing a smart agriculture device to aid small farmers with overwatering. The thesis includes a literature review investigating solutions for evaluating the water needs of crops, delves into insights gathered from interviews with Vietnamese small farmers, and data collected from their farms.

Build. Learn. Repeat. The three core actions of Tanagons, a learning kit designed for the K-6 classroom in teaching kids about the "other Rs" of sustainability: repair, repurpose, and reimagine. By examining societal trends related to these new approaches to waste management, along with considerations of current K-6 curriculum guidelines and how to optimize learning while following them, Tanagons creates a more comprehensive and engaging learning experience of this complex topic in hopes of preparing children to be more conscious individuals in the mission for sustainability.