Laboratory Experiment pubs.acs.org/jchemeduc
The Hazardous-Drums Project: A Multiweek Laboratory Exercise for General Chemistry Involving Environmental, Quality Control, and Cost Evaluation David Hayes† and Bozena Widanski*,‡ †
Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, United States Health and Science Department, University of Cincinnati, Clermont College, Batavia, Ohio 53103, United States
‡
S Supporting Information *
ABSTRACT: A laboratory experiment is described that introduces students to “realworld” hazardous waste management issues chemists face. The students are required to define an analytical problem, choose a laboratory analysis method, investigate cost factors, consider quality-control issues, interpret the meaning of results, and provide management with an action plan for implementation. This lab gives instructors the opportunity to introduce problem-based laboratory teaching method with real-life applications.
KEYWORDS: High School/Introductory Chemistry, First-Year Undergraduate/General, Environmental Chemistry, Laboratory Instruction, Safety/Hazards, Problem Solving/Decision Making, Collaborative/Cooperative Learning, Nonmajor Courses, Solutions/Solvents, Student-Centered Learning
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to do calculations, constructing a detailed data document, and developing analytical and critical thinking skills.
n the United States, as in any industrial country, hazardous waste is generated by a variety of businesses and continues to increase each year. The United States Environmental Protection Agency (EPA) estimates that industrial companies dispose around 7.6 billion tons of solid waste each year.1 Although this waste is under strict regulations by the EPA, if handled or disposed of improperly, the industrial waste can create considerable hazards to the environment, possibly, requiring expensive cleanup. Although there has been an increased interest in green chemistry to reduce waste within industrial companies and in academic laboratories,2 the education of young chemists in hazardous-waste management has been relatively neglected. Most of the undergraduate chemistry laboratories are still based on textbook exercises with the conventional experiments. In other words, it appears there have been limited attempts to introduce practical hazard-waste exercises to general chemistry courses.3−5 However, introducing chemistry students to hazardous-waste management issues early in their education can have a broad impact on their career choices and increase their awareness of environmental issues. The proposed lab exercise, “The Hazardous-Drums Project”, gives undergraduate chemistry students the opportunity to see, firsthand, the reallife problems chemists face with industrial waste. This project also helps to raise student awareness of the consequences that come when hazardous materials are disposed of improperly by such companies. In addition, students gain valuable field experience by increasing their chemical handling skills, learning © 2013 American Chemical Society and Division of Chemical Education, Inc.
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THE PROJECT
Real-Life Scenario
Forty-eight “55-gallon drums” containing varying quantities of a hazardous material were collected and separated by a chemical manufacturer, CHF, to allow for proper disposal. Some drums exceeded the federal regulatory threshold (FRT) value, but most drums did not. The drums that exceeded FRT were labeled and separated. Two unanticipated events occurred: all drum labels were washed away by a rainstorm and the secondshift workers indiscriminately relocated all 48 drums in a random order. Now the drums need to be retested and disposed. Another company, PDI, is willing to dispose of all of the drums for a high cost. CHF has asked a testing company, CTI, to evaluate the situation and come up with a reasonable analysis. All of the cost figures are available. The Procedure
“The Hazardous-Drums Project” laboratory exercise utilized the problem-based laboratory teaching method with real-life applications. In this laboratory class, students were introduced to the “hazardous-drums” problem and were playing the role of “Class Testers, Inc.” (CTI). In this project, they were informed that they should pretend to have 48 “hazardous drums” which, Published: March 12, 2013 473
dx.doi.org/10.1021/ed300202g | J. Chem. Educ. 2013, 90, 473−474
Journal of Chemical Education
Laboratory Experiment
exceeding FTR were missed during analysis. Serious consideration was required for bottom-line cost, for profitability concerns, for environmental impact, for good corporate citizenship, for compliance with Federal and State laws, and for the impact on the local community. Most students were upset at the beginning of the project, in light of being made to work almost every minute of available lab time. However, after the first week, students’ attitudes began to change and they started coming in to lab earlier and leaving a little later. They developed relationships with all their classmates, helping each other where needed, in spite of their ongoing debate regarding the dumping of hazardous material into the Ohio River, or whether they thought a classmate had “less than desirable” technique to apply to the situation. This project provided students with an idea of the challenge industrial chemists face when dealing with waste materials subject to federal regulation. Moreover, students were more aware of the environmental problems, quality control, and cost issues that can result from mishandling of industrial waste.
in reality, represented 40 salt solutions of sodium chloride that ranged from 4.504% to 4.991%, signifying drums under the “Federal Regulatory Threshold” (FRT) limit and 8 salt solutions that ranged from 5.164% to 5.579%, signifying drums that exceeded the FRT limit. After introducing students to the problem of missing all drum labels, the entire class participated in a discussion that initiated the team-building foundations. Lab leaders from the class were elected to “run the CTI company”, keep up with data collection, via a poster or chart on the lab wall, and conduct periodic class meetings to review the data and estimate the project’s progress. An important factor in this project was whether the drum exceeded FRT, not how close the sodium chloride value was to the actual prepared value. Students were asked to investigate cost factors, consider quality-control issues, interpret the meaning of results, and provide management with an action plan for implementation. Because most students had previously completed other general lab experiments, such as the separation and isolation of a chemical from a binary mixture, evaporation of one component from the solution was the designated choice for this project. The concept of an entire class becoming a team was introduced and multitasking skills were developed because students were still required to complete the regularly scheduled labs in addition to completing the project. Students were required to contribute for the overall good of the team, which was the entire class. Students received the information about the project on the second week of the quarter. The explanation of the project to the students took some effort, but resulted in an understanding of what was expected. At the end of each regular lab, the students spent about 30−40 min to do the analytical work and discussions. The students had six weeks to complete their projects and present the data. Some of the students prepared a rather large wall chart that became the headquarters for the testing company. Each student would write their test results on the chart and all students would review it for issues such as one test over the FRT limit, two tests under the FRT limit, and so forth. Also, the students were deciding if retesting was needed. The instructor did not involve himself or help in such cases. Finally, the students were determining among themselves whether proper techniques were being used for data determination and, in some cases, they assisted students who needed help. No student ever left lab early. This project needed 6 weeks for a successful completion.
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HAZARDS
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DISCUSSION
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ASSOCIATED CONTENT
S Supporting Information *
Instructions for students and instructions for instructors. This material is available via the Internet at http://pubs.acs.org.
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AUTHOR INFORMATION
Corresponding Author
*E-mail:
[email protected]. Notes
The authors declare no competing financial interest.
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REFERENCES
(1) United States Environmental Protection Agency Wastes Page. www.epa.gov/osw/nonhaz/industrial/guide/index.htm (accessed Feb 2013). (2) Ranke, J.; Bahadir, M.; Eissen, M.; Konig, B. J. Chem. Educ. 2008, 85, 1000. (3) Dunnivant, F. M. J. Chem. Educ. 2002, 79, 718. (4) Adams, D. L. J. Chem. Educ. 1999, 76, 1088. (5) Chang, J. C.; Levine, S. P.; Simmons, M. S. J. Chem. Educ. 1986, 63, 640.
For the purposes of this laboratory exercise, the hazardous material was 48 salt solutions (sodium chloride) ranging from 4.504% to 5.579%. Sodium chloride solutions are associated with no unusual hazards and should follow standard precautions of handling chemicals in chemistry lab.
This laboratory exercise was created for an undergraduate general chemistry course to educate young chemists in hazardous-waste management. Introducing a meaningful environmental matter to first-year chemistry students increased the motivation of students to appreciate the applicability of the chemistry they were learning. Students involved in this project were able to identify all drums that were under FRT limits as well as those that exceeded the FRT limits. Thus, no drums 474
dx.doi.org/10.1021/ed300202g | J. Chem. Educ. 2013, 90, 473−474
