PRODUCTION OF ETHANOL FROM FALSE YAM (icacina tricthantha) STARCH
The essence of this study was to produce ethanol from false yam starch which isa locally sourced material in order to minimize the energy cost and replacing a non-renewable energy (fossil) with a renewable resource. False yam tubershave been found to be suitable feedstock for ethanol production because it contains high amount of starch which was extracted through the following processing: sorting, washing, cutting, peeling, soaking, grinding, centrifugation, settlement, decantation, drying. After the successful extraction of starch, pretreatment follows, and enzymatic hydrolysis was carried using bacillus and the rate of hydrolysis was determined using iodine solution, benedictreagent, and DNS reagent. The fermentation process was carried out using saccharomyces cerevisiae (baker yeast). The experiment was designed by Box behnken using design expert with three factors which are temperature, time and reducing sugar concentration. The temperature was varied from 20ᵒC- 40ᵒC, time was varied from 48hours-168hours and reducing sugar concentration was varied from 2 – 6g/l, the fermented sample was distilled at 78°C.The statistical analysis also shown that the ethanol yield of 74.6% was obtain at optimized variable of 168hours time, 40oC temperature and 10g/l concentration. It can be concluded that the selected model was adequate to fit the date of response variable.
TABLE OF CONTENTS
Table of Contents v
List of Tables vi
List of Figures vii
CHAPTER ONE: INTRODUCTION
1.1 Background of the Study 1
1.2 Statement of the problem 1
1.3 Aim and Objectives of Study 2
1.4 Significance of the Study 2
1.5 Scope of Study 2
CHAPTER TWO:LITERATURE REVIEW
2.1 Historical Background and Overview of Ethanol Production 4
2.2 Usefulness of Ethanol as Fuel 5
2.3 Physico-Chemical Characteristic of Ethanol as Fuel 6
2.4 Impact of Ethanol Production to the Environment 7
2.5 Evaluation of Feedstock Use for Ethanol Production 8
2.6 Content of False Yam tuber 12
2.7 Enzymatic Hydrolysis 12
2.8 Fermentation 13
2.9 Distillation 13
CHAPTER THREE:MATERIALS AND METHOD
3.1 Raw Material and Enzymes Used 15
3.2 Equipment 15
3.3 Method 15
CHAPTER FOUR:RESULTS AND DISCUSSION 4.1 Result 20
4.2 Discussion 25
CHAPTER FIVE:CONCLUSION AND RECOMMENDATIONS
5.1 Conclusion 28
5.2 Recommendation 28
1.1 BACKGROUND OF THE STUDY
False yam (Icacina Trichantha) belongs to a family name Icacinaceae. It is a drought-resistant plasnt in West and Central Africa that produces a large tuber with a high starch content, but it is made up of anti-nutritive factors (terpenes) (Dei et al, 2011). It is found in countries like Senegal, Congo, etc. In Nigeria, especially Akwa Ibom State, this species of Yam is regarded as a non-edible plant and as unwanted plant. However, the tuberous root and leaves contains a high amount of starch used mainly for partial replacement source of energy for Broilers and animal feed, while it leaves also serve as medicine (David et al 2018). A reasonable quantity of starch can be extracted from the false yam tubers.
Feedstock used for production of Ethanol can be classified into the following categories: sugar containing materials (sugar beet, sugarcane), starchy materials (cassava, rice, corn, wheat and sweet sorghum etc), and Lignocellulosic biomass (cane bagasse, wheat straw, corn stalk, switch grass etc) (Muktham et al 2016). Ethanol is chemically called ethyl alcohol (C2H5OH). The conversion of starch into ethanol involves two processes which are sacharification: here the starch is converted to sugar using enzymes or amylolytic microorganism and follows by fermentation process, where sugar is converted into ethanol. Ethanol is a Colourless liquid, biodegradable, low in toxicity and environmentally friendly (Chin and Hng 2013). Gasoline when blend with ethanol help to reduce green house gas emissions by oxygenating the fuel mixture. It burns more completely. Ethanol is been used as addictive to gasoline, paint and cosmetics, it is used as biofuel.
1.2 STATEMENT OF THE PROBLEM
Globally, biofuel tend to be a source of remedy to world’s energy shortage. Ethanol has been regarded as energy panacea, the reason being that there are renewable unlike fossil. A critical look at feedstock used for ethanol production has post a serious problem to the availability of agricultural product for human consumption. In Nigeria fossil fuels are mostly used which is responsible for high carbon emission that leads to global warming.
This work desires to use starch from non-edible sources such as false yam (icacina tricthantha) as feedstock for production of ethanol.
1.3 AIM AND OBJECTIVES OF STUDY
The main aim of this study is to determine the percentage of ethanol produce from the fermented false yam starch.
This project upon completion will be able to fulfill the following objectives:
1. To extract starch from false yam tuber.
2. To produce ethanol from false yam starch.
3. To investigate the effects of process variables such as time, temperature and reduce sugar concentration.
4. To determine the optimum operating conditions
1.4 SIGNIFICANCE OF THE STUDY
An insight into the study of this work will reveal that false yam has an economic value as it contains important composition for ethanol production. It will also enlighten both the public and investors for the need to cultivate false yam as a plant especially the government of Akwa Ibom State and Federal Government at large.
1.5 SCOPE OF THE STUDY
This work entails with the use of false yam starch for production of ethanol which involves:
1. Identification and collection of raw materials
2. Preparation of raw material
3. Extraction of starch from the tuber
4. Production of ethanol from the extracted starch.