Experiment No. 1 Cpi.docx

Preparation of Ethyl Alcohol by Fermentation of Molasses and Alternative Raw Materials

A Research Study Presented to the Faculty of the Department of Chemical Engineering School of Engineering and Architecture Saint Louis University

In Partial Fulfillment of the Requirements for the Degree Bachelor of Science in Chemical Engineering

By Students

September 2018

i

ACKNOWLEDGEMENT

The researchers of this experiment would like to thank first our Almighty God for the benisons and wisdom that gave the researchers enough strength, knowledge and attitude to do and finish this experiment accurately and safely. The researchers are also very much thankful for the guidance and knowledge that their instructor, Engr. X , have imparted to them which helped a lot in the finalization of the papers and understanding of the procedures. Also, the SLU administration for lending the researchers the complete equipment to be used in the experiment. The researchers also like to extend their appreciation to those who are not mentioned here but somehow played a purpose on this activity.

ii

TABLE OF CONTENTS TITLEPAGE

i

ACKNOWLEDGEMENT

ii

TABLEOFCONTENTS

iii

LIST OF TABLES

iv

ABSTRACT

v

Chapter 1: INTRODUCTION

1

Chapter 2: DESIGN AND METHODOLOGY

5

Chapter 3: RESULTS AND DISCUSSION

7

Chapter 4: CONCLUSION AND RECOMMENDATION

8

REFERENCES

9

APPENDICES a. List and uses of Apparatus

10

b. Definition of Terms

13

c. Problems

14

d. Pictorials

15

iii

ABSTRACT VISCOSITY IS THE RESISTANCE OF A FLUID TO FLOW, IT RESULTS FROM INTERMOLECULAR ATTRACTIONS THAT IMPEDE THE MOVEMENT OF MOLECULES AROUND AND PAST EACH OTHER. THE EXPERIMENT WAS CONDUCTED TO DETERMINE THE ABSOLUTE VISCOSITY OF ORGANIC LIQUIDS AND THE RELATIONSHIP OF VISCOSITY AND DENSITY USING OSTWALD VISCOMETER. USING OSTWALD VISCOMETER, A DEFINITE VOLUME OF THE LIQUID WAS PLACED. THE LIQUID WAS ALLOWED TO FLOW OUT PASSING TWO CALIBRATED MARKS, AND THE FLOW TIME WAS MEASURED. THE DENSITIES WERE CALCULATED USING THE CONSTANTS AND FORMULA FROM THE HANDBOOK. THE VISCOSITIES OF THE LIQUIDS WERE CALCULATED BY APPLYING THE POISEUILLE'S LAW, WHEREIN VISCOSITY IS DIRECTLY PROPORTIONAL TO THE SAMPLE'S DENSITY, FLOW TIME, AND THE VISCOSITY COEFFICIENT. TO DETERMINE THE VISCOSITY COEFFICIENT, THE VISCOMETER WAS CALIBRATED USING DISTILLED WATER AS THE REFERENCE LIQUID. RESULTS FOR THE VISCOSITIES OF ORGANIC LIQUIDS (BENZENE, CHLOROFORM, METHANOL AND THE UNKNOWN) WERE 5.956x10-4 Pa•s, 6.4579x10-4 Pa•s, 6.8301x10-4 Pa•s , and 5.4631x10-4 Pa•s RESPECTIVELY. COMPARING THESE VALUES TO THE TRUE VALUES OF, IT WAS NOTICED THAT SOME WERE QUITE DIFFERENT. HOWEVER, IT CAN BE CONCLUDED THAT USING OSTWALD VISCOMETER IS AN EFFECTIVE WAY OF MEASURING ABSOLUTE VISCOSITY OF LIQUIDS.

iv

Keywords: Dumas Method, Ideal Gas Equation, molar mass

v

Chapter 1 INTRODUCTION

Fermentation is a chemical process by which molecules such as glucose are broken down anaerobically and it is foaming that occurs during the manufacture of wine and beer. Fermentation in a narrow sense to describe the changes brought about by yeasts and other microorganisms growing in the absence of air. Ethyl alcohol and carbon dioxide are not the only products of fermentation. Ethanol known as ethyl alcohol or grain alcohol is a flammable, colorless, mildly toxic chemical compound with a distinctive perfume –like odor, and the ethanol is found in alcoholic beverages. Natural energy resources such as petroleum and coal have been consumed at high rates over the last decades. The heavy reliance of the modern economy on these fuels is bound to end due to their environmental impact and to the fact that they might eventually run out. Therefore, alternative resources such as ethanol are becoming more important. Bio-ethanol is one of the most important renewable fuels contributing to the reduction of negative environmental impacts generated by the worldwide utilization of the fossil fuels. It is also used a solvent in many fields and used as a motor fuel additive. Ethanol is prepared by molasses fermentation. A residue begotten from sugar cane processing, molasses is the mother liquor left after crystallization of sugarcane juice. It is a dark colored viscous liquid that contains approximately 40 to 50% fermentable sugar. Being one of the earliest biotechnologies used by humans for the production of Ethanol, molasses Fermentation is also the most cost-effective way. Molasses is a microbiological energy source that helps in the process of growing yeast, bacteria and molds. Not only is it the most cost-

1

effective amongst the available energy sources for such industries but is also the easiest to incorporate in fermentation processes. Molasses Fermentation is a biological process in which sucrose from molasses is converted into cellular energy that eventually produces ethanol and carbon dioxide. Molasses from sugarcane or sugar imparts an appropriate substrate for ethanol production. They are the basic sources of sucrose which is present in them in concentrated sugar form. Fermentable sugars are directly used during Molasses fermentation and with the help of enzymes and reactions ethanol is formed. The Ethanol begotten from the whole process is used in the form of absolute or rectified spirit. .

In the fermentation of ethyl alcohol you can use many alternative raw materials like

fruit juice such as orange juice. Orange are dominant in our country and the over ripped oranges can be converted to very useful product which is the ethanol. The use of the fruit as a substrate for producing high added value products has been accomplished an example is spirits obtained by the fermentation and distillation of fruit . Fruit spirits are produced all over the world using various fruits, according to the availability in different countries and seasons. In this way, the current commercialization of known alcoholic beverages obtained from fruit could facilitate the market penetration of such spirits The process needed to produce fruit spirit is complex and involves various factors that influence the quality of the final product. However, the main physico‐chemical and sensorial differences among spirits are due to the particular composition of their corresponding raw materials like fruit, cereals, vegetables, etc and the fermentation process. Market‐orientated yeast strains are currently being developed for the competitive production of alcoholic beverages with minimized resource inputs, improved quality and low environmental impacts .

2

The orange juice, the initial sugar concentration was approximately 11ºBrix, and the pH was 3.7. The orange juice was mixed with a sucrose solution to adjust the sugar concentration to 16°Brix. Using some alternative raw materials in the production of ethanol is very essential and helpful to environment to minimize the use of resources. of organic liquids using the Ostwald viscometer. In order to achieve the goal, the following questions must be answered: (1) What is the flow time of the liquid, (2) what is the density of the liquid, (3) what is the temperature at the given density, and (4) what is the viscosity of the liquid? The measure of the viscosity in this experiment is the drag caused by the relative motion of the fluid and the surface while the flow conditions must have a sufficiently small value of Reynolds number for there to be a laminar flow. The Ostwald viscometer fulfils these conditions: A U-tube with two reservoir bulbs separated by a capillary. The liquid is added to the viscometer, pulled into the upper reservoir by suction, and then allowed to drain by gravity back into the lower reservoir. The time that it takes for the liquid to pass between two etched marks, one above and one bellow the upper reservoir, is measured. For absolute measurement we have to know all parameters of the viscometer (Viscosity coefficient) but we can calibrate the equipment using a reference liquid having well known density like water. Knowing the viscosity of the reference liquid, the viscosity of the liquid can be calculated. In doing this experiment, it is important that the students know beforehand the basic principle that the density is the main factor that brings about the differences in the viscosity of different liquids. The viscosity of the different liquids can be calculated from the constants and the formula given in the Perry's Chemical Engineers' Handbook. Also, viscosity varies with temperature. In general, the viscosity of a sample liquid decreases with increasing temperature and vice versa. Viscosity is normally independent of pressure. Since liquids are normally

3

incompressible, an increase in pressure doesn't really bring the molecules significantly closer together. Knowing the viscosity of a sample is important because it plays a major role to our daily lives. In the field of Chemical Engineering, viscosity measurement plays a big part in the industry. Viscosity is an important fluid property when analyzing liquid behavior and fluid

4

Chapter 2 DESIGN AND METHODOLOGY

This study focuses on preparing ethyl alcohol by fermentation of locally available materials like molasses. And determining or confirming the presence of ethyl alcohol in the fermentation mixture by standardization. The materials used are graduated cylinder, 500-ml round bottom flask, Erlenmeyer flask, beakers, stopper with bent tube, distilling flask, water condenser with rubber tubing, test tubes, watch glass, Pasteur pipette/dropper, iron stand, iron clamps, Bunsen burner and cotton. The reagents used are Molasses, distilled water, Pasteur’s nutrient and limewater. During the experiment 50 grams of Molasses was dissolved in 250 ml of distilled water placed in a 500 ml round bottom flask. When the molasses was thoroughly dissolved, 50 ml Pasteur’s nutrient was added. The mixture was shake thoroughly then the flask was closed with a stopper, fitted with bent tubes. The other side of the tube was attached to a test tube filled with 12 ml of limewater then it was sealed at the top with a cotton wad. The mixture was left in the locker for a week at room temperature. After a week, the fermentation process was completed. Without disturbing the mixture, it was the decanted and placed in a distilling flask attached to a water condenser. The mixture was then distilled, as soon as 2ml of sample was collected it was subjected to a combustion test then the next 5ml of sample collected was subjected to an iodoform test. In the combustion test, the 2 ml sample was placed in a watch glass and was ignited. While in the iodoform test, the 5 ml of KI solution was added to the 5 ml sample then drop by

5

drop KOH solution was added. It was set aside for an hour to wait for the formation of iodoform.

6

Chapter 3 RESULTS AND DISCUSSION 1. Observation for Combustion test The results of using both the molasses and the alternative raw material to prepare ethyl alcohol showed positive results in the combustion test. After being in contact with the flame of the match the sample distillate of both the molasses and the alternative raw material lit. The flame produce was bluish in colour with a tinge of orange. It can be said that both are combustible and volatile in nature.

2. Observation for Iodoform test Even after adding 5 ml of the solution iodine in KI and then with KOH solution drop by drop, since the distillate is with no color originally it was not decolorized in a sense because in the first place it was colorless. After setting the mixture for an hour, there were no formations of the iodoform.

7

Chapter 4 CONCLUSION AND RECOMMENDATION

Fermentation is a chemical process by which molecules such as glucose are broken down anaerobically and it is foaming that occurs during the manufacture of wine and beer. In the experiment done, it was proven that it is possible to prepare ethyl alcohol by fermentation of locally available raw materials like molasses and orange juice, in our case. The results of using both the molasses and the alternative raw material to prepare ethyl alcohol showed positive results in the combustion test. After pouring 2 ml of both sample distillates onto an evaporating dish, the sample distillate of both the molasses and the alternative raw material lit upon contact with the flame of the match. It can be said that both are combustible and volatile in nature. On the other hand, after performing the iodoform test it showed no reactions, even after adding 5 ml of the solution iodine in KI and then with KOH solution drop by drop. The distillate remained colorless and after setting the mixture for an hour, there were no formations of the iodoform.

8

References: Laboratory Test and Notebook for Organic Chemistry by Bossert, Roy and Wallace KL. Brode, 4th edition. Module on Science and Technology Education in the Phillipine Society by Tan, Merle C. Laboratory Courses in Organic Chemistry by Rosenblatt, David H.Laboratory Manual of Elementary Organic Chemistry by Richer, Ross. https://en.wujipedia.org/wiki/ethanol.

9

APPENDIX A LIST AND USES OF APPARATUS  Graduated cylinder - is a common piece of laboratory equipment used to measure the volume of a liquid. It has a narrow cylindrical shape. Each marked line on the graduated cylinder represents the amount of liquid that has been measured.  Round bottom flask- are often used to contain chemical reactions run by chemists, especially for reflux set-ups and laboratory-scale synthesis. This flask shape is also more resistant to fracturing under vacuum as a sphere more evenly distributes stress across its surface.  Erlenmeyer flask- its conical shape and narrow neck are its distinguishing features. Easy pouring and long term storage when used with a stopper reducing the evaporation of stored liquids & limiting contamination by airborne bacterial, fungal and chemical contaminants.  Beaker- is a cylindrical container used to store, mix and heat liquids in laboratories. Most are made of glass but other noncorrosive materials such as metal and heat-resistant plastics. It is usually have a flat bottoms and a lip around the top.  Stopper with stopper - is a truncated cylindrical or conical closure to seal a container such as a bottle, tube or barrel. It encloses a container from the outside without displacing the inner volume

10

 Distilling flask- is a round bottom and a long neck from which a side arm protrudes that is used to separate mixtures of two liquids with different boiling points  Water condenser- is a device used in the laboratory to cool hot gases into liquids. It is usually a long, circular glass tube inside the tube there is another smaller tube. The hot gas goes through the smaller inside tube while in the outside one cold water goes around. Water can be put in from the tap, and goes from the bottom to exit at the top.

 Test tubes- are usually made of glass for better resistance to heat and corrosive chemicals. It is used to handle chemicals especially for qualitative since their spherical bottom and vertical sides reduce mass loss when pouring, make them easier to wash out  Watch glass- circular concave piece of glass used in chemistry as a surface to evaporate a liquid, to hold solids while being weighed for heating a small amount of substance and as a cover for a beaker. It is also used as an evaporation surface, a watch glass allows closer observation of precipitates or crystallization, and can be placed on a surface of contrasting color to improve the visibility overall.  Pasteur dropper- is also known as droppers or eye droppers used to transfer small quantities of liquids. They are usually glass tubes tapered to a narrow point, and fitted with a rubber bulb at the top.

11

 Iron clamp – is a piece of laboratory equipment used to hold things and is placed in an iron stand to elevate and hold the equipment

 Iron stand- is a metal rod attached to heavy metal base and keeps the stand stable and vertical metal rod allows for easy height adjustment of the iron ring/clamp  Bunsen burner- device for combining a flammable gas with controlled amounts of air before ignition; it produces a hotter flame than would be possible using the ambient air and gas alone. It provides heat during the experiment.

 Cottons – it is used as bung or stopper instead of a rubber bung because the yeast-glucose mixture produces carbon dioxide as the fermentation process takes place which could cause a rubber bung to become dislodged.

12

APPENDIX B DEFINITION OF TERMS o Fermentation- is a metabolic process that consumes sugar in the absence of oxygen. The products are organic acids, gases, or alcohol. It occurs in yeast and bacteria. o

Ethyl alcohol - is the alcohol found in alcoholic drinks such as beer, brandy, or whiskey. It is made from the fermentation or chemical breakdown of sugars by yeast

o Molasses –black treacle, is a viscous product resulting from refining sugarcane or sugar beets into sugar. Molasses varies by amount of sugar, method of extraction, and age of plant. o Combustion test- a test performed wherein a sample liquid is to be ignited to find out certain substances compsing the sample. o Iodoform test- The reaction of iodine and base with methyl ketones is so reliable that the "iodoform test" (the appearance of a yellow precipitate) is used to probe the presence of a methyl ketone. This is also the case when testing for specific secondary alcohols containing at least one methyl group in alpha-position. o Nutrient salt solution – provides the essential mineral and nitrogen sources for the growing yeast cells so that they in turn can provide the enzyme zymase o Zymase - a mixture of enzymes obtained from yeast that catalyze the breakdown of sugars in alcoholic fermentation.

13

APPENDIX C PROBLEMS 1. Define fermentation. Discuss the process of fermentation. Fermentation is a metabolic process in which an organism converts a carbohydrate, such as starch or a sugar, into an alcohol or an acid. For example, yeast performs fermentation to obtain energy by converting sugar into alcohol. In the experiment done molasses was used as the sugar substituent. Bacteria perform fermentation, converting carbohydrates into lactic acid.

2. Give the complete reactions in the fermentation of molasses C12H22O11 +H2O C6H12O6

C6H12O6 +C6H12O6 C2H5OH + 2CO2

14

APPENDIX D PICTORIALS

The picture above illustrates the set-up done for the fermentation process of molasses after it was dissolved and prepared with the Pasteur’s nutrient solution

After a week of fermenting, the fermented molasses-ethyl alcohol is ready for distilling

The solution in the picture above was then distilled using the set-up shown in the image in the left. Using a fractionating column, the disllate was then used for other tests in the experiment

15

Two ml of the distillate was measured and was then placed in an evaporating dish. It was then ignited for the combustion test part of the experiment.

The raw material that was used in the experiment was orange. It was peeled, cut into smaller pieces and was then blended in the blender

16

The image above was the product after it was blended and placed in a thin cloth in order to extract the juice

The alternative raw material was then placed in a clean container ready for diistillation

17

After performing the same steps as the procedure done in the molasses fermentation, the fermented orange juice was then filtered in order for the pulps and residues to be discared and not be included in the distilling process

18

After fermenting the orange juice, it was then distilled in order to get the final product.

Combustion test was performed with 2 ml of distillate to determine the presence of alcohol in the product

19