Extraction Of Tannin From Indigenous Wood Species

TABLE OF CONTENTS

CHAPTER ONE

1.0     Introduction                                                                                      1

1. Statement of problem                                                              3
2. Aims                                                                                        4
3. Objectives                                                                                4
4. Limitation and delimitation                                                     4
5. Hypothesis                                                                              5

CHAPTER TWO                                                                  

2.0     Literature review                                                                     6

1. Extraction of natural products                                                          13

CHAPTER THREE 

3.0     Materials and preparation                                                                17

1. Raw materials                                                                         17
2. Apparatus                                                                               17
3. Preparation                                                                             18
4. Extraction/method                                                                            18
5. Flow process for extraction using hot water                                     19
6. Method                                                                                    20
7. Quantitative analysis                                                               21

CHAPTER FOUR

4.0     Result                                                                                                22

1. Percentage tannin                                                                    23
2. Discussion                                                                               23

CHAPTER FIVE                             

1. Conclusion And Recommendation                                                     24
   1. Conclusion                                                                              24
   2. Recommendation                                                                     25

References                                                                               26

CHAPTER ONE

1.0     INTRODUCTION

The tissue of wood, bark and leaves of trees contain a great variety of chemical substances of considerably scientific interest and some of the practical values.  Tannin is a generic name for widely occurring group of substances of vegetable origin.

Tannins from the bark, wood and leaves of certain species of plants is one of the most important commercial extractives which also form the basis of some important industries.  The main local source of obtaining industrial vegetable tannin in Acacia nilotica pods, obtained principally around Kano and Maiduguir.  Due to ever increasing demand for this materials by the producers of particle boards and leathers, there has grown a scarcity which normally manifest itself in the cost of materials.

Even in the southern parts of Nigeria where new leather industries are developing, the problem of obtaining transporting and storing these pods cannot for too long be over – looked there is therefore the need for a search into other alternatives in order to avoid a heavy drain on foreign exchange because of the importation of synthan (synthetic phenolic polymers).

Again the mangrove (Rhizophora species) found largely in most tropical coast lines contain reasonable amount of tannin.  But when used in the heavy tanning industries.  They a re known to produce an extract which has the major set back because of its hard red colour, which is prone to further darkening on exposure to sunlight during drying Fasina (1974) suggested that after full tannage is achieved, that the leather or particle board is bleached and then retanned using a light coloured fast penetrating vegetable tannin extract.  But one cannot over look here, the cost factor, since an industry is usually profit motivated.

This project is therefore an investigation carried out the determine other sources of vegetable tannin of commercial importance and which can sustain the available tanners industries in the country that is the species (bark and leaves) investigated were Pterocarpus Osun Pterocarpus Soyaureii. Burkea africana and Khaya senegalensis.

1.1     STATEMENT OF PROBLEM