Luverne High School Biology Class'
Ethanol Pages
Winning team(s) receives a BIG "ETOH cookie" for their efforts!
PowerPoint files do not contain movies, animations etc.
Movies:
Small Presentation Slide Show Menu
Interactive Ethanol Plant Tour
http://www.mda.state.mn.us/kids/ Video Fields of Energy from Minnesota Ag in the Classroom
pdf file of below activity this is updated each semester (due to the changing Internet component), current one is from October 2009. The activity below is from March 2005.
Here is the Spring 2010 activity in Word.
Fossil fuels are becoming very scarce. Fossil fuels also produce toxic pollutants that contribute to Global Warming and Acid Rain. Ethanol is a fuel that can be produced quite simply from many forms of carbohydrate mash.(i.e. corn, wheat, rice, sugar cane, wood, waste paper etc.) Since corn is so very plentiful in the United States at the present time, and probably into the 21st Century, it only seems logical to convert our abundant supplies into fuel-grade ethanol. Furthermore, ethanol burns at high octane and burns clean. In this lab procedure, you will use ordinary corn and simple enzymes to produce real ethanol.
Day One
1. Use your mortar and pestle to grind 110 grams of fresh corn to a 20 mesh size or smaller (approximately the size of sugar granules). Place your finely ground carbohydrate in a 500 ml Erlenmeyer flask (cap with foil).
Day Two
Your teacher will complete steps #2-5 to facilitate class times:
2. Add 350 ml of distilled water to the ground corn in a 500 ml Erlenmeyer flask. Stir thoroughly with the magnetic stirrer. You can leave the coated magnetic stirrer in your flask for stirring during the experiment. This is called mash.
3. Using Calcium Carbonate (alkaline) or HCl (acid) adjust pH of "mash" to 5.8 (optimum pH for enzyme action).
4. Add 0.5 ml of Alpha Amylase and stir. This enzyme will help to cleave long chains of sugar (starches) into shorter sugars the yeast organisms can use in fermentation.
5. Before class the teacher has autoclaved your mash at 225°F (110° C) for a minimum of 20 minutes. This process further breaks the long carbohydrates into usable sugars.
6. Remove from autoclave and cool to 190° F (84° C). (Oven at 190° F)
7. Add 0.5 ml of Alpha Amylase again and stir thoroughly (electric stir bar or swirling).
8. Stir occasionally for 1 hour while maintaining the 190° F temperature with the ovens provided. Internet searching as time allows.
9. At the end of 1 hour, cool to 90° F (32° C) by placing flasks in the 90° F water bath. If your mash is in a lump discard and add 100 g of glucose to 350 ml of d water.
10. Add 1 ml of Gluco-amylase to the mash. (sugar conversion enzyme)
11. Then immediately add 1 gram of yeast.
12. Stir thoroughly. Visible fermentation will start in a few hours.
13. Cap the Erlenmeyer with a stopper connected to a hose that is suspended in water. This will demonstrate CO2 production. Allow your flask to ferment for 48 hours at approximately 90° F. Check later today and tomorrow for CO2 production.
Day Three (Complete hydrometer activity / chromatography / Sweetness lab / Internet / Define Terms)
14. Allow fermentation to continue. When fermentation is complete the contents of the flask is considered "beer". Stirring during fermentation will maximize fermentation. Check for CO2 bubbling. Use Internet sites on biology homepage to answer remaining research questions.
Day Four
15. Mix your sample well and remove 50 ml of the beer to a plastic bottle which can be capped. Place this container in the freezer for HPLC (high performance liquid chromatography) analysis at Agri-Energy during our tour.
16. Filter the remaining "beer" from the mash through cheesecloth into a large beaker. Pour this liquid into another 500 ml Erlenmeyer for distillation.
17. Place the filtered mash on a flat tray and place in the oven for drying. The dried product will be distiller's grain, a high protein livestock feed. (100°-105° C)
18. Distill the "beer" at a temp. that does not exceed 195° F (90° C), or water will contaminate your ethanol sample. Use the set-up to the right. Record the vapor temperature every two minutes. The ethanol will distill at a temperature of 166°F (78.5° C). Vapor temperature will be around 90° C. Change condensation tubes as they fill about 2 fingers high or whenever the temperature leaves a plateau. Record these changes to be added to your graph. Build a spreadsheet of your data and print a graph for each team member. Indicate on the graph where you believe ethanol is being collected.
19. Test your distillate for purity by placing a small portion of your condensates on a watch glass and lighting it with a match. You should see a blue flame. (Do this in darkened room)
CONGRATULATIONS!!! You just produced fuel grade ethanol!
Day Five
Tour of Agri-Energy, LLC Fuel Grade Ethanol production plant.
Analysis of product by HPLC in alcohol plant laboratory.
Explain the term "value-added" as it related to producing ethanol from corn. A Biggee!!
1. What is Minnesota's law as to the use of oxygenates in gasoline? How has it changed since 1992?
2. Explain what an oxygenate is, then explain how it is used.
3. What is E85?
4. Describe what is meant by a "biological car". (Food and Energy)
1. What is a flex fuel vehicle? Which vehicles meet these requirements?
[http://www.cleanairchoice.com/outdoor/E85.asp]
2. Explain the advantages of flex -fuel?
3. Describe the requirements of the biodiesel legislation passed by the 2002 MN legislature. B2 law? [http://www.alamn.org/]
4. On October 22, 2004, President Bush signed into law the American Jobs Creation Act, how does that law affect ethanol and biodiesel?
1. Scavenge for the following "current" data:
ethanol’s economic impact $_______ # jobs __________
____ % MN corn into ethanol
MN has ____ ethanol plants producing ______ gallons ETOH per year
2. Identify the location of Minnesota's alcohol production facilities:
1. What is MTBE used for?
2. What is the problem with MTBE in California and other states that use it?
(All About Ethanol)
3. Many larger ethanol plants in MN are wet mill plants. What product is often produced in these plants?
4. What is meant by "batch" fermentation?
5. The ethanol is denatured after production. How and why is this done?
6. Some plants collect the CO2, what is it used for?
7. What is distiller's grain?
1. Why do potato wastes produce less ETOH than corn? (Where do potato wastes come from?)
The Science of Ethanol Production (search these out!)
1. Write a balanced equation for the fermentation of glucose.
2. Explain with a formula equation what happens to larger polymers like starches and sucrose before they can be used in fermentation. What is this process called?
3. What are some other examples of how people use fermentation?
4. Why was it necessary to grind the corn so fine?
5. List some other sources of carbohydrate that could be used in place of the corn?
Define the following terms:
milling alpha-amylase beer
saccharification distillation
denaturing mash
Questions from Plant field Trip:
Initialed by teacher before departure to plant! _____
Three (required) questions from you for personnel at Agri-Energy:
1.
2.
3.
Additional information from Luverne Agri-Energy (take notes):
bushels of corn? (% of Rock County)
alcohol produced (gallons)?
size of storage bins?
amount of DDG produced?
# of employees?
future of a soybean plant?
what will a soybean plant produce? what market? use
Additional info student gleaned from the ETOH unit:
The purity of the final alcohol produced by the Luverne ETOH plant is checked with a hydrometer. Hydrometers are long glass tubes with weighted bottoms. These tubes float in liquids of different densities at different levels. They are commonly used in industry for the quick determination of the purity of liquids. Salt water aquarium enthusiasts use hydrometers to make sure they have the right salt concentration in their water.
Complete the following inquiry activity.
1. Place the hydrometer in the 3 identified liquids. Draw a picture of your results below:
2. Determine the density of the unknowns A & B. Show any math (you find necessary). Be sure to label all work.
3. Explain in written form how you determined your answers.
TO THE STUDENT:
Welcome to this experimental science exercise. We hope that you will find it interesting and worthwhile. Carefully read through these directions and the directions on the next page before you begin to work.
You may be part of a group for the first part of this exercise. Each group should carry out the experiment and collect the data together, but each student must record the data in his or her own packet. Be sure to record the data exactly as you observe them. After the data has been collected, each student should answer the questions independently.
After you have finished your experiment and have recorded all of the data, you will be asked to answer some questions about the experiment and the data you recorded. Your answers must be written in this test booklet in the space provided. Make sure that you understand each question before you begin to write. At any time while you are writing your answers, you may look back to the directions for the experiment and the data you collected. Be sure that your answers are written as clearly and neatly as possible.
Before you turn the page, read the list of materials given below and check to make sure that your group has everything listed.
Materials
*cup *filter paper *tap water *paper towels
*rulers *candy *pen or pencil
Paper Chromatography
In developing a food product, you would want to consider the chemical content of its ingredients. For instance, since consumers with certain allergies may need to know about the dyes used in food, you should be able to identify the dyes in your product.
Paper chromatography is a process that can be used to separate the components of a mixture. The advantage of this process is that relatively small quantities of substances, including food components, can be detected in a simple and fast manner. Mixtures or solutions of metals, dyes, blood, urine, or antibiotics, for example, can easily be separated by the various chromatographic methods available to chemists today.
In this activity you will apply the analytical technique of paper chromatography to examine the dyes found in the colored shells of candy.
Read all of the instructions before proceeding. You will be working with your team while performing the experiment and collecting the data. Both partners are responsible for recording the data. You will be working alone while responding to the questions. Your teacher will tell you where all the materials you need are located.
* Be careful to handle the filter paper only by the edge.
* Draw a horizontal line in pencil approximately 1.0 cm from the short end of each strip of filter paper. Lightly draw a dashed line approximately 2.0 cm from the opposite end. See the demo set-up!
* Add tap water to the cup to a depth of about 0.75 cm. The water level in the cup must be below the level of the first line you drew.
* Moisten a green, yellow, or brown candy. Now rub the candy's coating on the filter paper. Your goal is to transfer colored coating onto the paper. Transfer colored coating onto the paper in the area just above the first pencil line you drew.
* Repeat this procedure so that you have green, yellow, and brown candy coatings on three different strips of filter paper.
* Make sure that the chromatography paper has thoroughly dried before proceeding further and that you have labeled each strip with a G, Y, or B to help you remember what color coating is on each strip. The labeling should be done at the top of the strip above the dashed line.
* Carefully lower each strip into the water in the cup. Do not lower any of the strips beyond the 1 cm pencil line you marked previously. Hold each strip in place until the water has risen on the strips to the dashed line, or for 5 minutes (whichever comes first). Tip: It may be more convenient for you to do one strip at a time.
* Do not throw your chromatography strips away. You will need to analyze the results in Question 1.
* After you have finished, be sure to clean up your work area.
Please answer the following questions by yourself.
1. Describe the components of each dye used in the candy coatings based upon the chromatography you have just performed.
2. What characteristic(s) of the dyes might be responsible for the observations you made.
3. Organic chemists, as well as other scientists, often use this technique to determine if a chemical reaction has occurred or to separate the components of a mixture. Explain, using an example, how and why the result from this type of analysis are useful.
Objectives: Students will develop an understanding of isomers of certain simple sugars.
Students will complete and be able to explain the process of serial dilution.
Students will perform a serial dilution to allow the determination of the comparative sweetness of glucose and fructose.
Students will complete an Internet search to further discover the chemistry and physiology of sweet taste.
Background: You have already been exposed to the terms glucose and sucrose during unit one. As you might recall sucrose is a double sugar with the empirical formula C12H22O11, and glucose is a simple sugar with the empirical formula C6H12O6. Fructose is a simple sugar with the the same empirical formula as glucose. Fructose is widely sold in health food stores. It is a popular sugar substitute because it is sweeter than glucose and thus requires less sugar to give a certain sweetness.
Materials: bathroom paper cups (5) tap water
food grade fructose (1 g) sterile stirring rod
food grade glucose (1 g)
Procedure:
1. Label your 5 cups as: 10% glucose, and fructose #1 to fructose #4.
2. Add 1g glucose to 10 ml water in the 10% glucose cup.
3. Add 1g fructose to 10 ml water in the fructose #1 cup
4. Place 8 ml of water in fructose cup #2 and 9 ml water in fructose cups #3 and #4.
5. Using a clean, new bulb pipette transfer 2 ml of fructose #1 to fructose #2 (swirl).
6. Using your pipette transfer 1 ml of fructose #2 solution to fructose #3 solution (swirl).
7. Using your pipette transfer 1 ml of fructose #3 to fructose #4 (swirl).
8. Use your clean stirring rod to taste a drop of the 10% glucose solution. Now proceed to test the comparative sweetness of each cup. Record your data.
Data: Design a table to record your sweetness data:
1. Show calculations for determining the % sugar in fructose cups 1-4.
2. Which fructose cup has the closest sweetness to the 10% glucose cup?
3. Determine mathematically approximately how many times sweeter fructose is than glucose.
1. Draw the most common chemical structures of glucose and fructose:
2. Do certain areas of your tongue appear to be be more sensitive to sweetness? Design an experiment to test your hypothesis and try it with one of your sugar solutions. Label the sweet sensitive area on the diagram:
3. Why would dieters want to use fructose as a sweetener?
4. Where can fructose be found in nature?
5. Can you find in the scientific literature or hypothesize on your own what chemically makes fructose sweeter than glucose?
HPLC Read out from Agri-Energy:
Ethanol Production
http://www.ethanol.org/
1. Milling: The corn (or barley or wheat) will first pass through hammer mills, which grind it into a fine powder called meal.
2. Liquefaction: The meal will then be mixed with water and alpha-amylase, and will pass through cookers where the starch is liquefied. Heat will be applied at this stage to enable liquefaction. Cookers with a high temperature stage (120-150 degrees Celsius) and a lower temperature holding period (95 degrees Celsius) will be used. These high temperatures reduce bacteria levels in the mash.
3. Saccharification: The mash from the cookers will then be cooled and the secondary enzyme (gluco-amylase) will be added to convert the liquefied starch to fermentable sugars (dextrose), a process called saccharification.
4. Fermentation: Yeast will then be added to the mash to ferment the sugars to ethanol and carbon dioxide. Using a continuous process, the fermenting mash will be allowed to flow, or cascade, through several fermenters until the mash is fully fermented and then leaves the final tank. In a batch fermentation process, the mash stays in one fermenter for about 48 hours before the distillation process is started.
5. Distillation: The fermented mash, now called "beer," will contain about 10% alcohol, as well as all the non-fermentable solids from the corn and the yeast cells. The mash will then be pumped to the continuous flow, multi-column distillation system where the alcohol will be removed from the solids and the water. The alcohol will leave the top of the final column at about 96% strength, and the residue mash, called stillage, will be transferred from the base of the column to the co-product processing area.
6. Dehydration: The alcohol from the top of the column will then pass through a dehydration system where the remaining water will be removed. Most ethanol plants use a molecular sieve to capture the last bit of water in the ethanol. The alcohol product at this stage is called anhydrous (pure, without water) ethanol and is approximately 200 proof.
7. Denaturing: Ethanol that will be used for fuel is then denatured with a small amount (2-5%) of some product, like gasoline, to make it unfit for human consumption.
8. Co-Products: There are two main co-products created in the production of ethanol: carbon dioxide and distillers grain. Carbon dioxide is given off in great quantities during fermentation and many ethanol plants collect that carbon dioxide, clean it of any residual alcohol, compress it and sell it for use to carbonate beverages or in the flash freezing of meat. Distillers grains, wet and dried, are high in protein and other nutrients and are a highly valued livestock feed ingredient. Some ethanol plants also create a "syrup" containing some of the solids that can be a separate production sold in addition to the distillers grain, or combined with it. Ethanol production is a no-waste process that adds value to the corn by converting it into more valuable products.
Teacher notes:
Internet URL's
http://www.luverne.k12.mn.us/school/science/luvernebmarks.html
Luverne Biology Bookmarks. Ethanol links in Unit 2.
http://www.ethanol.org/
American Coalition for Alocohol
http://www.mncorn.org
MN Corn Growers
http://hplc.chem.shu.edu/book1/Introduction/int_typs.html
http://kerouac.pharm.uky.edu/asrg/hplc/history.html
HPLC sites
Water bath can be made with plastic tubs and hot/cold tap water mixed.
We use chemistry ovens for the 190° F (84° C).
Distiller's grain dries quickly- overnight gets a little crispy.
Fields of Energy Worksheet