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Chapter 11
Leveraging Student Interest in Environmental Topics for Undergraduate Research in an Interdisciplinary Environmental Research Cluster Neelam Khan, Sang H. Park, David P. Pursell,* and Kathryn Zimmermann School of Science and Technology, Georgia Gwinnett College, 1000 University Center Lane, Lawrenceville, Georgia 30043, United States *E-mail:
[email protected].
Undergraduates are interested in applied research focusing on environmental issues. To capitalize on this interest, four faculty members at Georgia Gwinnett College formed an interdisciplinary environmental research cluster so as to encourage undergraduate participation in research on these issues. The four cluster faculty include a physicist, chemist, environmental engineer, and environmental toxicologist. The cluster faculty support undergraduate environmental research by sharing resources and students while working on varied aspects of a suite of projects. Over the past five years, more than 50 students have participated in environmental cluster research projects. Student researchers have been 62% women and 48% under-represented groups, as defined by the National Science Foundation. This chapter briefly highlights three recent projects: river water analysis through popular recreational canoe and kayak routes in Georgia; toxic substances air sampling and environmental justice; and production of biodiesel from waste cooking oil and grease from campus dining operations. Biodiesel project details are then presented to illustrate the depth of student research experiences.
© 2018 American Chemical Society Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
1. Introduction Georgia Gwinnett College (GGC) is a 4-year, public college in the University System of Georgia. The college was founded in 2006 and has rapidly grown to more than 12,000 students in just over 10 years. Admissions are non-competitive and most students are commuters who live and work in the greater metropolitain Atlanta area of north Georgia. The college is comprised of five schools, including the School of Science and Technology (SST), which offers academic programs in biology, chemistry, environmental science, exercise science, information technology, and math. As part of their academic program, all SST students complete a one semester internship with local industry/agency or independent research under the direction of faculty. As a new college, research facilities, instrumentation, and funding support are limited. In addition, 4-year college faculty have heavy teaching and service loads which inhibit, in a practical sense, faculty effort on research activities. While many studies highlight the significant and positive contributions of undergraduate research to increasing STEM retention (1–5), engaging our students in meaningful independent research projects presents logistical and financial challenges for faculty and the administration. To help overcome these challenges, four faculty (condensed matter physicist, environmental engineer, chemical physicist, environmental toxicologist) formed an environmental research cluster. Cluster faculty re-tooled their research programs to correspond to widespread student interest in environmental topics. The cluster faculty share facilities, instrumentation, resources, and grant proposal preparation. Each student has one official mentor, but to capitalize on faculty research expertise, cluster facuty work with all students on the varied aspects of their projects. This approach allows faculty to pool resources (both financial and temporal) to incorporate many students working on a project each semester. The cluster approach has proved successful in recruiting student researchers from GGC and the Gwinnett School of Math, Science, and Technology (GSMST), the local public, science magnet high school. From 2012 to 2017, 56 students of have conducted environmental research as shown in Table 1.
Table 1. Research Student Demographics Students
M
F
Wt
Bk
As
Hi
GGC
35
9
26
10
10
10
5
GSMST
21
9
12
2
8
10
1
Total
56
18
38
12
18
20
6
NSF Demographic Categories: Male (M), Female (F), White/non-Hispanic (Wt), Black/African-American (Bk), Asian (As), White/Hispanic (Hi). Other catagories not represented among our students
182 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
Students have driven the research agenda by selecting topics and projects of particular interest to them. Cluster faculty then provide support (safety, techniques, and instrument training; supplies, chemicals, and solvents; project objectives, timelines, and reporting) to make the projects scientifically and experimentally meaningful student research experiences. Faculty meet regularly with the students throughout the semester to provide students hands-on assistance with particularly challenging techniques, work through issues as they arise, help maintain student focus on project objectives to ensure progress, and provide encouragement as students develop their research skills. A sampling of project titles listed below illustrates the breadth of student environmental interest.
• • • • •
• •
• • • •
Georgia Adopt-A-Stream Water Quality Monitoring Project Community Innovations Project-Air Quality and Environmental Justice Analysis of Waste Oil and Grease from the Campus Chick-fil-A for use as Biofuel Synthesis of Biodiesel from GGC’s Used Oil Using Size Averaging to Evaluate Heavy Metal Accumulation in Shells of Asiatic clams (Corbicula fluminea) as Biomarkers for Environmental Toxicity Designing Methods for Phytoremediation of Lead in the Georgia Gwinnett College Community Garden Elemental Analysis of the Organ systems of the Fetal Pig via Flame Atomic Absorption Spectroscopy and Inductively Coupled Plasma Mass Spectrometry Chemical Analysis via Atomic Absorption Spectroscopy of a Campus Ecosystem during Intense Construction Activity Chemical Analysis of Kudzu Roots via Atomic Absorption Spectroscopy Oil and Grease (O&G) Determination in Water on GGC Campus Ecosystem via FTIR Optimization of CO2 Adsorbents for Carbon Capture and Sequestration
2. Overview of Three Recent Projects The environmental research cluster has enabled undergraduates to participate in numerous community-based, public interest, environmental projects aligned with their interests. This chapter includes a brief overview of two ongoing projects, as well as an in-depth report of a third (and more complete project) demonstrating the breadth of student interests and strategies to engage them in meaningful, applied research.
183 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
2.1. Analysis of Heavy Metal Content in the Conasauga, Oostanaula, and Coosa Rivers during Paddle Georgia 2016 This unique project combined components and collaborators from industry (PerkinElmer), academia (GGC), state entities (Georgia Adopt-A-Stream and Georgia Environmental Protection Division), and citizen scientists. Figure 1 illustrates the collaboration overlaid on the site plan for collection and analysis of 84 different water samples along the Coosa River Basin.
Figure 1. The Georgia river basins project forged a lasting collaboration between industry, government, and academia by integrating collection and anlysis of water samples for heavy metals at 84 sites along the Coosa River Basin. 184 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
Water samples from the Conasauga, Oostanaula, and Coosa Rivers were collected by volunteer citizen scientists during the Paddle Georgia Trip 2016. These citizens were trained and offered technical support by the Georgia Adopt-A-Stream (AAS) program, which is supported by the Georgia Environmental Protection Division (EPD) (6). During the 1970’s, the Coosa River Basin was contaminated by numerous sources, including the industrial carpet industry. During the period of 1960-1990, the river was viewed as unfit for recreational purposes (7). Participants in Paddle Georgia gathered samples for analysis of trace metals at 84 sites along the Coosa River Basin. Other data collected included air and water temperature, pH, dissolved O2 (ppm), conductivity (µS/cm), total hardness (ppm), total alkalinity, and turbidity (NTU). The samples collected by citizen scientists, aided and trained by Georgia AAS staff, were analyzed by two GGC undergraduates interning at the PerkinElmer Technical Center in Johns Creek, GA. PerkinElmer provided students initial ICP-MS training and access to the instrument. Faculty worked in concert with PerkinElmer personnel to mentor the students through their internship. Students prepared the unfiltered samples for hot block digestion in dilute HCl and HNO3. Quality assurance measures such as blank and spike recovery samples were included. Samples were analyzed for trace heavy metals and mineral composition on a PerkinElmer NexION 350D, using Kinetic Energy Discrimination (KED) with helium to remove polyatomic interferences. The undergraduate students presented this work as a poster at ACS regional and national conferences, as well as the Georgia AAS Confluence conference. The students brought their expertise back to the GGC campus in subsequent work supporting the environmental cluster using GGC’s recently acquired PerkinElmer Elan ICP-MS instrument. Although preliminary results of this project are outside of the scope of this manuscript, it is expected that this project will support a future publication involving undergraduate authors.
2.2. Measurement of Hazardous Air Pollutants and Policy Analysis in Metro Atlanta: Environmental Justice This project used the theme of environmental justice to create an interdisciplinary and collaborative research team that included students and faculty from GGC’s SST and School of Liberal Arts (SLA). Figure 2 graphically portrays the project’s collaborations. Environmental justice is broadly defined by the U.S. Environmental Protection agency as “the fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income with respect to the development, implementation, and enforcement of environmental laws, regulations, and policies (8).” This project, internally funded by GGC’s Community Innovations Project (CIP) program, partnered two faculty and seven undergraduate students with an external advisor at the Atlanta-based environmental law firm, GreenLaw. 185 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
Figure 2. The environmental justice air pollution project fostered faculty collaborations between groups interested in social justice. This community-based inquiry sought to analyze gas-phase hazardous air pollutants, specifically polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), at sites selected by students based on community demographic parameters such as income, percent minority population, and linguistic isolation. The measurements were made using passive air samplers (PAS), which are a low cost alternative to traditional active sampling methods of gas-phase organic pollutants. Because PAS are low-cost and require no power, samplers of this type can be used to increase the spatial resolution of gas-phase PAHs studies, allowing for comparison concentrations in communities with differing socio-economic characteristics, or for continuous monitoring purposes (9). The concentrations of PAHs and PCBs in the gas-phase were compared to demographic data to investigate the issue of environmental justice in the Atlanta metropolitan region. The project served two primary objectives for the research students. In the first objective, GGC students experienced both field and laboratory work through deployment of PAS to sample PAHs and PCBs. The collaborative student team (two biochemistry, one environmental science, and four legal studies students) worked together in the laboratory to quantify the analytes in each sample, as well as conduct quality control experiments (laboratory and field blanks, spike 186 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
recovery experiments, response factors of deuterated internal standards). The students also worked collaboratively on the acquisition of US Census data for the specified sampling locations, including parameters such as percent minority populations, percent below poverty populations, and percent living in linguistic isolation. The combination of both lab and policy work for all students ensured experiences outside of students’ area of expertise and communication between social and physical scientists. In the second objective, the collaboration of students with an outside partner, as well as the communities in which they placed samplers, gave students exposure to professional development opportunities, networking, and practice in communicating the goals and methods of their projects to an audience outside of academia. Results relating to both the concentrations of hazardous air pollutants, demographic analysis, and student response to interdisciplinary research are beyond the scope of this chapter, but are expected to be published in a different venue.
2.3. Synthesis and Analysis of Waste Oil and Grease (O&G) from the Campus Chick-fil-A for Use as Biofuel The third highlighted project, and the focus of the remainder of this chapter, is the work of environmental cluster faculty, GGC students, GSMST students, GGC dining operations, and multiple external collaborators in synthesizing and characterizing biofuel from waste O&G. Figure 3 graphically portrays the biodiesel project.
Figure 3. The biodiesel project developed on and off campus collaborations in coverting waste O&G into useful fuel. 187 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
The interdisciplinary nature of this project engages students majoring in chemistry, biology, and environmental science, as well as young investigators from GSMST with interest in sustainability and renewable energy resources. Current challenges regarding traditional petrochemical sources of energy facilitate the need for alternative fuel sources, such as biodiesel. Biodiesel is an alternative fuel that has potential for reducing both greenhouse gas and hazardous emissions. Though many different types of feedstocks are available for the generation of biodiesel, it can be created from waste O&G. The project also addresses a possible avenue for a sustainable disposal method of campus waste O&G, since current disposal methods are both costly and may contaminate environmental matrices. The biodiesel project uses waste O&G from the Chick-fil-A restaurant on campus. Current objectives include research into the sustainability of a campus-wide biodiesel production effort, bench-scale biodiesel production using well developed transesterification reactions, and physical and chemical characterization using equipment and instrumentation available at GGC, much of which students have used directly in their other course work. The concept of biofuels is reasonably well developed and several undergraduate laboratory excercises or classes have focused on creating and/or characterizing biodiesel (10–13). However, the unique aspect of this project is to refine the bench scale production and characterization of biofuel from locally sourced (on-campus) waste oil and grease while simultaneously conducting a detailed cost-benefit analysis of scale-up opportunities as an environmentally sustainable process to fuel on-campus four-wheeled vehicles. The biodiesel project begain in Fall 2016 and results presented in this chapter cover work through Spring 2017. The project is ongoing and anticipated to continue for several additional semesters. Each semester faculty conducted safety, techniques, and instrument training for GGC undergraduate students and the high school students from GSMST. We have recently recalled students from previous semesters, who had become proficient with the various processes, to conduct training for the new research students. Faculty outlined the project goals and timelines for the semester, provided background references, and students self-organized and began work. Students synthesized all biodiesel, generated all data using equipment and instrumentation at GGC, and conducted analysis of the data. Faculty met regularly with students during each semester to discuss progress, suggest approaches to work through problems, replenish supplies, and suggest next steps. At the end of the each semester, the cluster faculty and all students met to consolidate results and analysis and provide guidance for the student presentation at the college wide research and creative activities symposium. Students then prepared and presented their work to faculty and students at the symposium.
188 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
3. Details of the Biodiesel Project 3.1. Background The increase in industrialization and population has led to the increased need for energy. The primary sources of this energy are coal, petroleum, natural gas, hydro and nuclear (14). Projected world energy consumption indicates that liquid fuels, mostly petroleum-based, coal, and natural gas will be the dominant energy sources in future as shown in Figure 4 (15). The high price of petroleum products, decrease in fossil fuel reserves and atmospheric pollution created by use of petroleum-based fuels are just some of the motivation for alternate energy sources (14, 16–18). The use of vegetable oil as fuel originates with Rudolph Diesel, the inventor of the diesel engine. He fueled his engine with peanut oil in the Paris exhibition of 1900. Since then a number of studies have shown the promise of vegetable oil use as an alternate fuel for diesel engines. However, the high viscosity, low volatility, and poor cold flow properties of vegetable oils result in severe engine deposits. Polymerization of vegetable oils under high pressure and temperature, injector coking and piston ring sticking have also prevented direct use of vegetable oil as a fuel in diesel engines (17, 19–21).
Figure 4. Projected world energy consumption. Reproduced with permission from ref. (15). U.S. Energy Information Administration (May 2016).
Many researchers have worked to develop vegetable oil based derivatives that approximate the properties and performance of petroleum based diesel fuel. The most common method for production of biodiesel is transesterfication, shown in Figure 5, in which the vegetable oil or animal fat (triglyceride) reacts with a monohydride alcohol in the presence of a catalyst to create the corresponding mono alkyl esters (20, 22, 23). However, the high manufacturing cost of vegetable oil is a major barrier in the commercialization of biodiesel production. Waste cooking oil, which is virtually expense free compared to pure vegetable oil is 189 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
a promising alternative for the production of biodiesel (24, 25). Moreover, the production of biodiesel from waste cooking oil will reduce the challenge of its disposal and possible contamination of land and water resources. The ability to prepare diesel fuel from waste cooking oil would partly decrease the dependency on petroleum-based fuel, focusing on a more carbon neutral approach to energy (16, 22, 26). Biodiesel production using waste cooking oil and its characterization have been conducted by various researchers. Previous studies have compared the use of different types of catalysts, alcohol/oil mole ratio, temperature, reaction time, and pre-treatment methods for the production of biodiesel (27–30). In addition, different characterization methods have been employed to determine various chemical and physical properties of the generated biodiesel (16, 30–34).
Figure 5. General transesterification reaction.
3.2. Biodiesel Synthesis The biodiesel production via transesterification combines waste O&G (triglycerides), methanol, and sodium hydroxide to produce glycerol and three fatty acid methyl esters (FAMEs) (20, 27, 35–37). Students tried several stoichiometric proportions of reactants and obtained best results using 1 mol triglyceride to 6 moles methanol. Students combined filtered waste O&G (420 g) from Chick-fil-A, CH3OH (300 g), and dried NaOH (4.2 g, 1% mass of O&G) in the reaction apparatus shown in Figure 6a. The reaction proceeded at 65 °C for 2.5 hours under reflux with stirring. The reaction was paused and the bottom layer of glycerol was removed. The reaction then continued for an additional 45 minutes. Afterwards, the reaction solution was transferred to a separtory funnel, and it remained there overnight to enable further separation of glycerol as shown in Figure 6b. After the removal of glycerol, the remaining biodiesel solution was washed with 2 M HCl followed by DI water until the wash water achieved pH 7. The washed biodiesel was oven dried for 1 hour at 100 °C. Figure 6c shows the filtered waste O&G contrasted with the finished biodiesel product in Figure 6d. 190 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
Figure 6. Experimental set-up for biodiesel reaction: a) reaction vessel; b) post-reaction separation of methyl esters from glycerol and other waste; c) crude waste oil and grease from Chick-fil-A; d) finished biodiesel product.
3.3. Biodiesel Physical Characterization and Analysis After synthesizing biodiesel, students then conducted physical and chemical characterization of their product using many techniques they learned in their previous course work.
3.3.1. Biodiesel Density
Methods Injection systems, pumps, and injectors must supply an amount of fuel precisely adjusted to provide proper combustion, thus density is considered an important property of fuel (38). Density of biodiesel was determined by measuring the mass with increasing volume of 5 ml aliquots at three different temperatures.
Results Figure 7 presents student density plots and correspondingdensity values at 22.4 °C, 36.3 °C and 65 °C. The experimental value of density at 22.4 °C was compared to a calculated density determined by a linear combination of biosiesel composition fraction and literature density values. Composition fractions were determined via GC-MS analysis (see Section 3.4.1). Based on components of methyl oleate [cis-9] (69.5%), methyl linoleate [cis-9,12] (20.3%), methyl 191 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
palmitate (10.2%), methyl stearate (0.1%) the calculated density is 0.874 g/ml. This is compared to an experimental density of 0.85 g/ml, giving a 2.8% error. The density versus temperature trends in Figure 7 correspond with the expected trend of decrease in density as temperature increased, although the measured difference is small.
Figure 7. Mass versus volume plots and curve fits at 22.5, 36.3, and 65.0 °C, and biodiesel density determined from the plots.
3.3.2. Biodiesel Kinematic Viscocity
Methods. Fuel with high viscosity leads to poorer atomization upon injection into the combustion chamber, cold weather injection issues, and poor lubrication for the precision fit of fuel injection pumps, resulting in poor performance (39, 40). The American biodiesel standard (ASTM D6751) optimal kinematic viscosity for biodiesel at 40 °C ranges from 1.9 – 6.0 mm2/s (41). Students determined kinematic viscosity of their biodiesel following the ASTM D445 method at 40 °C using the Cannon-Ubbelohde viscometer (Figure 8a) and a PolyScience viscosity bath (Figure 8b). The viscometer and bath were operated at 40 °C, with 20 minutes provided for temperature equilibration. Efflux time (time for biodiesel to flow a certain distance in the viscometer under gravity) was then measured. Efflux time for biodiesel was recorded as it flowed from mark E through F in Figure 8a. 192 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
Figure 8. Viscosity apparatus: a) Ubbelohde viscometer with demarcations for positions used for measuring efflux time; b) temperature-controlled viscosity bath with viscometer set into the bath.
Results Using the Ubbelohde viscometer constant (0.04810 mm2/s2 for viscometer used for waste O&G, 0.01087 mm2/s2 for viscometer used for the biodiesel), students determined the kinematic viscosity of their biodiesel at 40 °C as 4.6 mm2/s using Equation 1. 193 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
The kinematic viscosity of students’ biodiesel lies well in the range for biodiesel viscosity according to ASTM D6751. Biodiesel kinematic viscosity of biodiesel was compared to that of waste used oil using the ASTM D445 method. Kinematic viscosity calculated for waste used oil was 42 mm2/s at 40 °C which is approximately 9 times higher than the viscosity of biodiesel. Table 2 summarizes kinematic viscosity results for waste O&G, student biodiesel, and ASTM D6751 biodiesel standards.
Table 2. Biodiesel Kinematic Viscosity at 40 °C Sample
Ave Efflux Time (s)
Kinematic Viscosity (mm2/s)
Filtered waste O&G
870
870*0.04810=42
Biodiesel
422
422*0.01087=4.6
Biodiesel ASTM D6751
----
1.9 – 6.0
3.4. Biodiesel Chemical Characterization and Analysis 3.4.1. Biodiesel Components via GC-MS
Methods Students analyzed biodiesel samples using the Shimadzu QP2010S Gas Chromatograph Mass Spectrometer (GC/MS) with HP 88 column (60 m x 0.25 mm, i.d., 0.20 µm film thickness) in scan mode to determine fatty acid methyl ester (FAME) composition. Analyte retention times and confirmations were compared to a standard mixture of 37 fatty acid methyl esters (FAMEs, in methylene chloride, Restek, Bellefonte, PA). 20 mg of student generated biodiesel was dissolved in 10 mL of methylene chloride (Fisher Scientific, HPLC grade) and injected as 2 µL in split mode (50:1) at a constant column flow of 2.0 mL/min. The GC oven temperatures were held at 175 °C for 10 min, ramped at 3 °C/min to 220 °C with a final hold for 5 min. The GC/MS interface was maintained at 250 °C and the MS ion source temperature was 230 °C.
194 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.
Results The FAME profile of the biodiesel generated from GGC waste cooking oils was determined by GC-MS analysis method described above. The retention times of individual peaks of the gas chromatogram were verified against a FAME standard mixture and individual FAMEs were identified using the MS database (NIST library data). A representative chromatogram, mass spectrum of major components, and biodiesel mixture composition are shown in Figure 9.
Figure 9. Representative gas chromatogram and mass spectrum.
Relative percentages of FAMEs were calculated from the total ion chromatogram by integration and results are presented in the Table 3. The student biodiesel from waste O&G consists of 10.2 wt.% of methyl palmitate (C16:0), 69.5 wt.% of methyl oleate (C18:1), 20.3 wt.% of methyl linoleate (C18:2), and
