ALCOHOL AND BIOMASS PRODUCTION USING WASTE PAPER THROUGH ENZYMATIC METHOD

ABSTRACT

Bioconversion of waste materials into useful products is very topical not only to protect natural resources, but also to limit environmental pollution. In this study, waste paper was enzymatically hydrolysed using crude enzyme from Trichoderma viridae for alcohol and biomass production. The T. viridae was maintained on sabouraud Dextrose Agar (SDA) slants. Spores from fully grown slants were dislodged into sterile saline containing 0.05% (v/v) Tween 80. The spores suspension was transferred into an enriched medium with carboxymethyl cellulose (CMC) as sole carbon source to induce cellulase synthesis. After seven days of fermentation, the filtrate of the medium was centrifuged and the obtained supernatant was used as the crude enzyme source. The waste paper was ground into powder and pretreated at 1210C for 15 minutes. The crude enzyme was transferred to the pretreated paper and the mixture was incubated at 370C for 72 hours for hydrolysis to take place. The sugar content and the specific gravity of hydrolysate were 6.94% and 1.033g/cm3 respectively. The hydrolysate sugar content was optimized with 67g of sugar (sucrose) and the sugar content rose to 21.54% while the specific gravity rose to 1.114g/cm3. After 7 days of fermentation of the hydrolysate with Baker’s yeast, the sugar content and specific gravity dropped to 2.59% and 1.005g/cm3 respectively while the pH reduced from 5.6 to 3.1. The temperature fluctuated between 290C and 300C with biomass production and alcohol yield of 1.99g/l and 89.0% respectively. Optimizing enzymatic hydrolysis parameters and proceeding to secondary distillation could give a better yield. 

TABLE OF CONTENTS

Pages

Title Page ﾿ i

Certification ﾿ ii

Dedication ﾿ iii

Acknowledgements ﾿ iv

Table of contents ﾿ v

List of tables ﾿ viii

List of figures ﾿ ix

Abstract ﾿ x

CHAPTER ONE: INTRODUCTION ﾿ 1

1.1 Introduction ﾿ 1

1.2 Aims and Objectives ﾿ 3

CHAPTER TWO: LITERATURE REVIEW ﾿ 4

2.1 Constituents of paper ﾿ 4

2.1.1 Cellulose ﾿ 4

2.1.2 Hemicellulose ﾿ 4

2.1.3 Lignin ﾿ 5

2.2 Alcohol production from cellulosic materials ﾿ 5

2.3 Pretreatment ﾿ 7

2.3.1 Physical pretreatment ﾿ 7

2.3.1.1 High pressure steaming ﾿ 7

2.3.1.2 Hydrothermal pretreatment ﾿ 8

2.3.2 Chemical Pretreatment ﾿ 8

2.3.2.1 Dilute acid pretreatment ﾿ 8

2.3.2.2 Hydrogen peroxide pretreatment ﾿ 8

2.3.2.3 Lime pretreatment ﾿ 9

2.3.2.4 Ammonia fiber explosion (AFEX) ﾿ 9

2.3.2.5 Organosolv pretreatment ﾿ 9

2.4 Enzymatic hydrolysis and Microbial Cellulases ﾿ 10

2.5 Ethanol fermentation ﾿ 11

2.6 Biomass ﾿ 11

CHAPTER THREE: MATERIALS AND METHODS ﾿ 12

3.1 Materials ﾿ 12

3.2 Methods ﾿ 12

3.2.1 Processing of Waste paper ﾿ 12

3.2.2 Pretreatment of waste paper ﾿ 12

3.3 Media preparation and sterility test ﾿ 12

3.4 Microorganism and inoculums preparation ﾿ 13

3.5 Submerged fermentation for cellulase production ﾿ 13

3.6 Enzymatic hydrolysis of pretreated waste paper ﾿ 14

3.6.1 Sugar analysis ﾿ 14

3.6.2 Measurement of soluble liquid ﾿ 15

3.6.3 Optimization of sugar content ﾿ 15

3.7 Alcohol fermentation ﾿ 15

3.7.1 Determination of pH and temperature ﾿ 16

3.7.2 Determination of Titratable Acidity ﾿ 16

3.7.3 Determination of Biomass production ﾿ 17

3.7.4 Alcohol content ﾿ 17

3.8 Biomass separation ﾿ 17

3.9 Distillation ﾿ 18

CHAPTER FOUR: RESULTS ﾿ 19

CHAPTER FIVE: DISCUSSION, CONCLUSION AND RECOMMENDATION ﾿ 30

5.1 Discussion ﾿ 30

5.2 Conclusion ﾿ 31

5.3 Recommendation ﾿ 31

REFERENCES ﾿ 33