Environmental Science
Oxidized Biochar-Modified Ammoniated Titanium Phosphate (A-TiP-OB) Nanoparticle Synthesis for Sustainable Strontium Recovery from Produced Water
Friday Stout
The University of Texas at Arlington
Stable strontium is a critical mineral (CM) for industry, medicine, and research applications. Although strontium is naturally found in the minerals of celestite (SrSO4) and strontianite (SrCO3), conventional mining is limited due to strontium availability. Produced water, a by-product of hydraulic fracturing, is abundant in strontium, but current recovery technologies are costly. Many studies have employed low-cost adsorption technologies to remove strontium, but few have investigated desorption for elemental recovery. In this study, a novel synthesis of ammoniated titanium phosphate (A-TiP) nanoparticles is modified with oxidized biochar to improve recovery of strontium from produced water. A-TiP can potentially be improved by adding oxidized biochar to increase active binding sites that are selective for Sr2+ ions. Using elemental analysis of Fourier Transform Infrared (FTIR) and x-ray diffraction (XRD) spectra, modification of A-TiP with oxidized biochar has proven to uptake strontium from a 0.0117 M Strontium chloride (SrCl2) solution with 0.16% Sr composition compared to 0.13% using non-oxidized biochar A-TiP (A-TiP-NOB), proving that using oxidized biochar with A-TiP (A-TiP-OB) improved strontium uptake. Next, we will optimize phosphorous content and run batch experiments assessing the effects of contact time, and desorption-adsorption. Additionally, our A-TiP-OB will be compared with pure A-TiP and oxidized biochar for comparison with previous studies that investigated these materials individually.
Protective Pigmentation in Saxicolous Lichens of the Lemitar Mountains, New Mexico
Ronan Fast
Baylor University
Hot deserts (BWh) are classically regarded as barren or near-inhospitable due to the domination of evaporation processes over precipitation. The scarce moisture that can be retained in these porous, rocky soils is typically insufficient in supporting energy-expensive vegetation such as hardwoods – as a result, vegetation is often limited to shrubs, grasses, and succulents. The Chihuahuan Desert, including the Lemitar Mountains of Central New Mexico, is one such desert. However, even as plants become scarce, lichenized fungi are present across the range in a myriad of colors. Diverse pigmentation in lichen serves to shield the symbiont’s delicate photosynthetic partner from environmental stressors, such as intense ultraviolet radiation, aridity, and oxidation. By categorizing lichen observations in the Lemitar range by family and genera, we can point to specific metabolic compounds that provide crucial protections. When considering annual climatic conditions and hot desert biogeochemistry, inferences can be made about the relationship between protective pigmentation and an extreme environment. In this review, I expect to observe a trend in pigment chemistry across the twelve recorded lichen families, particularly toward anthraquinones and melanic compounds that support UV-shielding in a region of high elevation and minimal vegetative coverage.
Defining the Quality Attributes Required when Scaling-Up Nanoliposome Production for Agricultural Applications
Christopher Rodriguez
Baylor University
The global agricultural industry has been plagued by persistent pests, which are increasingly tolerant to pesticides, resulting in millions of dollars in crop losses each year. Conventional pesticides are less effective today than in the past due to overuse, resistance, and their non-systemic nature. There is a need to develop formulations that improve systemic circulation and prevent resistance. This project uses nano-encapsulation chemistry (i.e., nanoliposome formation) to enable the transduction of normally non-systemic pesticides through crop plant tissue, expanding the systemic options available to growers. Encapsulation is effective for targeted delivery in biomedical (small-molecule therapeutics) and agricultural (pest control) uses, and there is a need to scale up synthesis for field applications. However, the process for scaled-up production has yet to be optimized and accepted by regulatory authorities and manufacturers. To achieve acceptance, specific quality attributes (i.e., physicochemical characteristics) must be defined and measured routinely to demonstrate consistency across batches. To address this knowledge gap, 1 L of pesticides encapsulated in nanoliposomes was produced in small volumes (<10 mL batches), sonicated, and dialyzed for 24 hours. The resulting batches were characterized for primary particle size, size distribution, aggregation state, surface charge, encapsulation efficiency, and systemic distribution using dynamic light scattering, electron microscopy, and liquid chromatography-mass spectrometry. The individual measurements were subsequently compared and showed reproducibility. A test was conducted to ascertain whether batches could be combined, and it was concluded that they could not. This study established a framework for defining the quality attributes required when scaling up nanoliposome production for agricultural applications. Future research will focus on evaluating environmental safety assessments.