In the Laboratory
Implementing Temporary Facilities for Organic Chemistry Laboratory Judith C. Amburgey-Peters Department of Chemistry, College of Wooster, Wooster, OH 44691;
[email protected] Our classroom and laboratory facilities desperately needed to be expanded and renovated. We were teaching 250 to 300 students in the chemistry department each semester, in a building that was constructed in 1902 and last remodeled in 1960. Annually, 60 to 80 students were enrolled in the organic chemistry course and laboratory. Our challenge was to update the facilities with minimal interruption of instruction and research. After considering new building construction versus utilization of the old building, the decision was made to renovate and expand the existing building. The next question was whether to do the work over several years, while occupying portions of the building, or to vacate the building and complete the entire project as quickly as possible. The decision to vacate the building was made easier by the fact that we have three other science buildings on campus, and we had strong support from our administration and faculty in the other science departments. We moved out of the building, and the project was completed within 17 months with minimal interruption of class and laboratory schedules. Keys to successful implementation of temporary laboratory facilities are planning and knowledge. When I started to plan, I received some assistance by word of mouth, but I could not find published resources that provided the physical and experimental details I needed. The Project Kaleidoscope Web site1 is an excellent resource for planning new facilities and renovations of existing facilities, but information about establishing interim facilities is very limited or nonexistent. This article is intended to share specific ideas for setting up a temporary wet-chemistry laboratory, and general strategies from which a broader audience may create their own solutions. Our planning relied on administrative support that in turn recruited support from the chairs of the other science departments. During planning, the department divided the workload because the building manager, who is also a chemistry faculty member, was too busy to deal with the minute details of every laboratory. I found that as the organic chemist, I not only needed to invest a good deal of time thinking and planning for the permanent facilities, but I also needed to take the lead in securing arrangements for the temporary organic laboratory facilities. A significant part of the departmental planning included the relocation budget, which ultimately we had underestimated at $100,000. For us, the organic laboratory consumed a major portion of the relocation funds (Table 1). However, to offset the costs, I agreed to sell as much of the equipment purchased for the temporary laboratory as possible. Once the temporary facilities were planned, the curriculum was assessed in terms of what needed to be kept and what needed to be changed without compromising the organic curriculum, the educational experience, and student safety. I worked with a summer student intern to assess the curriculum, set up the facilities, and evaluate the feasibility of the experiments in the available
Table 1. Budget for the Interim Organic Laboratory Estimated cost a
Item Equipment Hoods b Aspirator pumps Water pumps
$65,235 2,400 700
Plumbing (safety shower, ice machine installation)
In-house work
Electrical (circuit panel, outlet installation)
In-house work
Carpentry (risers for counters and tables)
In-house work Total
$68,335
aAll
costs are the 1998 dollar amounts and reflect academic discounts. bIncludes 10 AC4000, 3 AC600, and 33 multilayer filters and 13 prefilters. The 1998 replacement cost of one multilayer filter was $450.
facilities. Ultimately, the temporary space provided a trial run for the new permanent space that we now occupy. As would be expected, proper laboratory ventilation was the limiting factor for all wet-chemistry experiments. With the exception of organic chemistry, all laboratory courses were modified so that rooms with limited or no hood space would be sufficient. Various arrangements were made so that the research students who needed to do wet chemistry could either work off campus or share the few hoods available on campus. The remaining question was how to teach organic chemistry laboratory with 60 students enrolled. We explored several options, none of which was feasible for our specific circumstances. These included using the facilities of local high schools or other higher-education academic institutions. However, the local high schools and academic institutions did not have the space to accommodate our needs. We also considered renting mobile buildings (trailers), but we did not have the land space to house them. We even had brief discussions about canceling or postponing the laboratory portion of the course, but this would have delayed an entire class of chemistry and biochemistry majors and disadvantaged students preparing for the various healthrelated entrance exams (MCAT, DAT). Instead, as the result of support from the administration and science department chairs, a 23 × 30–ft (690 sq ft) room normally used for general physics laboratory was made available. By comparison, our new, permanent organic chemistry laboratory space is 28 × 38 ft (1064 sq ft) with a maximum occupancy of 24 students. Organic Lab Scheduling We had three laboratory sections, which met Tuesday, Wednesday, and Thursday from 1:00 to 3:50 p.m. Each section was limited to 20 students and had two laboratory assistants in addition to the instructor. Having two laboratory assistants was essential mainly because the stockroom and the temporary
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organic laboratory were located in different buildings. AC4000
AC4000
AC4000
AC4000
Existing Facilities We had a 35-seat classroom adjacent to the general physics lab, where the pre-laboratory lecture was held. The laboratory space had built-in tables along the north and northeast walls and most of the south and southwest walls (Fig. 1). Most importantly, the room had water sources: four water spigots with cup sinks along the south wall and a medium-sized sink on the west wall. There were also three relatively large movable tables (3.5 × 7 ft) in the middle of the room, each having electrical outlets on the floor, and two smaller tables.
AC 600
AC 600
608
AC 4000
AC 4000
AC 600
N ice
AC 4000
sink
Facilities Modifications In addition to having the physical space, the major considerations for setting up a functional organic laboratory were proper fume control, electrical needs, water supply, and safety issues. After conducting organic laboratory experiments in units from three major vendors of ductless fume enclosures,2 we decided to purchase units from AirClean Systems. Some key features of the ductless fume enclosures were (i) integral bottoms, which are important in the event of a spill, (ii) electronic monitoring module for filter usage and chemical safety, and (iii) the versatility and quality of the filters. The size of the physics laboratory permitted 10 large AC4000 units and 3 smaller AC600 units (Fig. 1), referred to as hoods throughout the rest of this article. As we unpacked the hoods, we kept all of the original packing material to facilitate repackaging for storage or relocation. After the hoods were set up, two one-inch holes were drilled into the right, rear side for the circulating water system tubing as described below. The large hoods were customized by AirClean Systems with a removable stainless steel plate in the bottom of each unit that protected the polypropylene from the aluminum hot-blocks that we use in lab. Because the hoods are ductless, they have minimal impact on electrical demands or heating and cooling. For long-term use, the multilayered filters are the only major cost related to these units (Table 1). The filters are rated for approximately two years of use (2000 blower hours), so we did not have to replace any filters. Sufficient electrical capacity was needed for the hotplates, hoods, ice machine, three rotary evaporators, three water-circulating aspirator vacuum pumps, an FTIR spectrophotometer, and eight MEL-TEMP units. To accommodate the electrical load, an additional circuit panel was installed in the room and the circuits were distributed to the equipment locations. Each hood had a 6-outlet power strip that plugged into the wall; this permitted electrical access at the front of the hood for the circulating water pumps and hot-plates. The electrical circuits were distributed along the wall so that each power strip was plugged into its own circuit. Plumbers installed an ice machine in the room and a safety shower in the rest room located immediately adjacent to the lab (within 100 feet). Ideally, the safety shower and eyewash would have been installed in the lab. However, the space in the lab and in the hallway directly outside of the lab would not accommodate a safety shower. Each hood needed a circulating water supply for the jacketed condensers used for distillations and reactions under reflux. Enough five-gallon buckets, tubing, pinch clamps, and
AC 4000 AC 4000
AC 4000 Glassware “wash station”
MEL-TEMPs
FT-IR
Phone
Rotary Evaporator
Rotary Evaporator
Rotary Evaporator
cupsink
Figure 1. Floor plan of the temporary organic chemistry laboratory facility.
circulating water pumps4 were gathered to set up an icecooled circulating water system for each hood. The buckets were located adjacent to the hoods, and the water tubing was run through the side of the hood. Two major advantages to the self-contained recirculating water systems were that water consumption was reduced and the largest “flood” risk was less than five gallons of water. The hoods needed to be situated at a comfortable working height. Platforms were installed to raise the height of the built-in tables from 30 in. to approximately 36 in. for eight of the larger hoods. The space under the platforms was used as cubbyholes for storage of safety glasses, paper towels, and gloves. The movable tables, which held two larger hoods and one smaller hood (Fig. 1), had leg extenders attached to raise the tables to a comfortable working height. The increased height of the tables also provided additional storage space underneath. Safety The safety shower with eyewash was installed as described above. Portable eyewash bottles were also available in the lab. A fire extinguisher was located in the room, as were chemical spill kits and a mercury cleanup kit. We connected a phone in the lab for use in the case of emergency and to contact the stockroom. Rubberized floor mats were placed in front of the glassware wash station and ice machine. We prepared the facilities to be as safe as possible, and we had no problems. Laboratory Logistics Before we moved out of the chemistry building, the chemicals and supplies needed for the two-semester organic laboratory were categorized and boxed by experiment as much
Journal of Chemical Education • Vol. 79 No. 5 May 2002 • JChemEd.chem.wisc.edu
In the Laboratory
Table 2. Laborator y Curriculum for First- and Second-Semester Organic Chemistr y during the Interim Year Expt First Semester
Second Semester
I
Thermometer calibration and identification of an unknown by recrystallization and melting point determination
Separation and purification of ferrocene and acetylferrocene by column chromatography
II
Isolation of caffeine by extraction and recrystallization
MacNMR and spectral review identification of an unknown using spectral methods
III
Conformational analysis
The Diels–Alder reaction
IV
Isolation of eugenol from cloves
Friedel–Craft alkylation of phenol nitration of an unknown N-acyl aniline
V
Introduction to MacSpartan investigation of carbocation stability
Oxidation of aromatic side chains
VI
Preparation of an alkene
Reactions of a Grignard reagent
VII
Alkene analysis by GC and IR spectroscopy
Qualitative organic chemistry (4 weeks)
VIII
Bromination of trans-stilbene
Synthesis of a dipeptide
IX
Enzymatic reduction of a ketone
Deprotection of a dipeptide
X
Reduction of an unknown ketone
—
XI
TLC separation of plant pigments
—
as possible. Most of the essential chemicals were stored in plastic containers. Ideally, portable chemical cabinets would have been used, but space was not available in the lab or in adjacent areas of the physics department. Instead, the necessary chemicals were transported to the lab for each experiment and kept in the hoods during the lab session. Hazardous chemicals were stored in a portable, ventilated chemical storage building purchased from part of the relocation budget.3 The chemical storage building is now used in our physical plant facilities to store various volatile chemical supplies. The students needed containers or drawers that would safely and conveniently store their equipment. We used 20 four-drawer plastic containers and added two bolts at the back of each drawer to prevent the drawers from pulling completely out. The 20 equipment containers provided students in a lab section with their own equipment, but every student shared equipment with one student in each of the other two afternoon sections. Ideally, each student would have had his or her own lockable equipment drawer, but space was not available. In our permanent lab facilities, each student has a key to his or her own locked equipment drawer. Because the room had only one medium-sized sink, three wash stations including a soapy water bin and a clean-water bin were set up along the counter with the sink (Fig. 1). The plastic bins were a little deeper than a typical dishpan to help minimize spillage. Two medium-sized portable drying racks were located behind the plastic washing tubs. Distilled water rinses or ethanol rinses were performed using wash bottles in the student hood. We chose to use ethanol as the organic cleaning solvent rather than acetone. However, given the efficiency of the hoods, acetone would have been fine. Temporary waste beakers were placed in each hood, and their contents were transferred to the appropriate waste container at the end of each lab. The waste containers were stored in one of the AC600 hoods, along with any solvents necessary for that week’s experiment. The other two AC600 hoods were used to house the balances and the necessary solid reagents. Our only source of distilled water was located in a different building. Each week several 5-gallon plastic water containers were used to transport distilled water for the circulating water vacuum pumps, rotary evaporators, and student use.
Equipment/Instrumentation We had three rotary evaporators located in the room, which were cooled using recirculating4 ice water in a 5-gallon bucket as described above. Circulating water aspirator pumps5 provided the vacuum necessary for the rotary evaporators and for suction filtration when needed. We are still using the circulating pumps and aspirators, which greatly reduce the environmental impact of our rotary evaporators while simultaneously increasing their efficiency. An FTIR spectrophotometer was also located in the lab. Other pieces of equipment (GC, NMR, etc.) were set up in laboratories in the biology or geology buildings. During the labs that required use of the equipment located in other buildings, one lab assistant was in the organic lab and the other was stationed at the instrument. The instructor rotated between the two locations as needed. When students needed to have NMR spectra collected, they prepared the samples and submitted them to the student NMR instrument operator for data collection. Curriculum Our laboratory curriculum was virtually unaffected during use of the interim organic laboratory facilities. Table 2 shows the lab schedule for both semesters of organic chemistry while we were in the interim facilities. In the first semester, only experiments II and V were modified or substituted. In experiment II, we normally purified caffeine by sublimation, but during the interim year we recrystallized the caffeine instead. Experiment V was originally the preparation of chlorocyclohexane, which generates HCl and SO2 gases. We were not comfortable with this risk and instead developed a lab using MacSpartan (Wavefunction, Inc.) for the “Investigation of Carbocation Stability”. In hindsight, we could have prepared the chlorocyclohexane. However, in our current lab curriculum we have continued the MacSpartan exercise and have not reintroduced the preparation of chlorocyclohexane. In the second semester, we normally include the synthesis of a benzhydrol ether, in which the product is purified by vacuum distillation. We removed this experiment from the interim schedule and allowed two weeks for experiment VI, the Grignard reaction. We have put synthesis of a benzhydrol
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ether back into our current laboratory curriculum. Originally, we believed we would also need to replace experiment VII, our four-week “qualitative organic analysis in the identification of an unknown,” with the computational package MacSqualor (Trinity Software). However, after the first semester in the interim lab, we realized that we could reasonably conduct our qualitative lab by limiting the students to the identification of one unknown and preparation of one derivative, rather than two. The most significant challenge in the qualitative work was the limited hood space for the storage of the necessary chemicals and reagents. In Retrospect A larger room would have provided more flexibility, but overall, the interim facilities served our needs very well. Some key limitations included (i) only one entrance/exit doorway, (ii) the limited chemical storage space in the lab, and (iii) not having the safety shower in the same room. In the event of emergency evacuation, we did leave extra space by the doorway to the room. Since space was limited in the lab, many of the chemicals were stored in the chemical storage building and had to be transported weekly. This certainly required extra preparation time and planning. Even though the plumbed safety shower and eyewash were not in the lab, several portable eyewash bottles were present in the lab. Ultimately, all of our preparations proved necessary and adequate. Conclusions Successfully setting up the laboratory depended on the financial and facility support from our institution, the electrical, carpentry, and plumbing work conducted by our physical plant departments, and extensive planning and attention to detail. The hoods were the largest financial investment, and as agreed during the planning, the larger hoods have been sold. Our
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temporary organic laboratory in the math/physics building was considerably more environmentally friendly than our old laboratory space. Overall, the temporary space was crowded and some of the experimental arrangements were quite “creative”. However, good citizenship on the part of the students, professors, and laboratory assistants made implementation of the two-semester laboratory in temporary facilities possible. Everyone involved, including the “residents” whose building we occupied, was pleasantly surprised by how successful the organic laboratory was under such unusual circumstances. Even though the circumstances were not ideal, the experience was worthwhile to sustain our organic curriculum and to get the facilities that we have now. Notes 1. The Project Kaleidoscope (PKAL) Web site (http:// www.pkal.org/facility/index.html) (accessed Mar 2002) provides excellent information about planning for new facilities. 2. AirClean Systems, 7605 Welborn St., Raleigh, NC 27615; http://www.aircleansystems.com/, 1-800/849-0472. ERLAB–North America, Captair LabX, Inc., One Elm Square, 1980 Turnpike St., North Andover, MA 01845; http://www.erlab-dfs.com/us/index.html; 1-800/964-4434. Misonix Incorporated, 1938 New Highway, Farmingdale, NY 11735; http://www.misonix.com/, 1-800/645-9846. (accessed Mar 2002) 3. Haz-Stor’s prebuilt portable structures engineered for chemical storage. Haz-Stor/Justrite, 2454 Dempster St., Des Plaines, IL 60016, Subsidiary of Federal Signal Corporation; 847/294-1000; http://www.thomasregister.com/olc/justrite/. (accessed Mar 2002) 4. Little Giant submersible recirculating water pumps (501003 Model 1) available directly from Little Giant Pump Company (http://www.lgpc.com/index.html ) or through VWR (http://www.vwrsp.com/). (accessed Mar 2002) 5. Cole-Parmer Recirculating Water Aspirator Pump (dual channel model number 07049-00); http://www.coleparmer.com/catalog/, 1-800/323-4340. Used pumps can be found. (accessed Mar 2002)
Journal of Chemical Education • Vol. 79 No. 5 May 2002 • JChemEd.chem.wisc.edu
