PRODUCTION OF PURIFIED BIOACTIVE COAGULANT FROM MORINGA OLEIFERA BY MICROFILTRATION FOR LOW TURBIDITY

WATER TREATMENT

BY

EMAN N. ALI

A thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy in Engineering

Kulliyyah of Engineering International Islamic University Malaysia

AUGUST 2010

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ABSTRACT This study is focused on developing an efficient processing technique for Moringa oleifera seeds to produce natural coagulant for use in drinking water treatment. The produced natural coagulant can be used as an alternative to aluminum sulphate and other coagulants worldwide for water treatment. The use of present coagulant materials produce high sludge volumes needs pH adjustments, which means adding more chemicals, and the cost of water treatment is increasing rapidly. A potential solution to these problems is the production of a new natural, renewable, environmentally friendly and safe coagulant/flocculants from Moringa oleifera seed to be used in drinking water treatment. This study investigates processing Moringa oleifera seeds to concentrate the bio-active constituents which have coagulation activity. Moringa oleifera seeds were processed for oil extraction using electro thermal soxhlet. Isolation and purification of bio-active constituents was done by chromatography technique. HPLC was used to determine the molecular weight of the bio-active constituents. The molecular weight of bio-active constituents was in a low range of between 1000 – 6500 Dalton. The importance of determining the molecular weight of bio-active constituents is to find the cut off size for the proposed cross flow filtration (ultrafiltration) method. The bio-activity was determined using conventional jar test procedures, using synthetic water and river water samples. The major water quality control parameters monitored during the study was the residual turbidity for the synthetic and river water with low, medium, and high initial turbidity. The results showed residual turbidity of less than 5 NTU which is recommended by World Health Organization (WHO). The turbidity removal was found to be 95.5%, 98.5%, and 99.3% for low, medium, and high turbidity river water samples, respectively. The proposed method to isolate and purify the bio-active constituents is the cross flow filtration method, which produced the natural coagulant with very simple technique (oil extraction; salt extraction; and microfiltration through 0.20 µm). The water treatment parameters of low speed, mixing time, and the dose of processed Moringa oleifera were optimized. The optimum conditions were: 40 rpm (low speed) with mixing time of 41.28 min, the dose of processed Moringa oleifera was 0.69 mg/L. The optimum conditions of regression model were verified using synthetic and river water with low turbidity. The regression model was highly significant with p-value < 0.01 for all model terms. The turbidity removal was up to 95.1% using low initial turbidity river water without any additives. The initial river water turbidity of 32.4 NTU was reduced to residual turbidity of 1.6 NTU by using 0.75 mg/L of processed Moringa oleifera with low mixing speed of 40 rpm for 41 minutes. The microfiltration method is considered to be a practical method which needs no chemicals added. The natural coagulant produced was used with low dosages to get high turbidity removal which considered to be a breakthrough in this study and recommended to be scaled up for industry level. This product is commercially valuable at the same time it is minimizing the cost of water treatment. The production of this alternative coagulant locally can contribute to the economic development of Malaysia. The by-products (cooking oil, activated carbon, animals feed, and fertilizer) can be of an additional advantage. It is concluded that this is a zero waste industry.

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البحث صملخّ

نتاج خمثّر طبيعي كبديل عن سلفات االملنيوم واملواد املخّثرة االخرى تطوير تقنية جديدة الترّكز هذه الدراسة على إن إستعمال املواد احلالية ينتج كميات كبرية من النفايات، كما حيتاج إاىل معاجلة . املستخدمة عامليًا يف معاجلة املياه

وكحل ممكن. املياه يف إزدياد مستمر ذي حيتاج إىل إضافة مواد كيمياوية أخرى كما إن كلفة معاجلةحامضية املياه، واليف معاجلة ههلذه املشاكل هو إنتاج خمثّر طبيعي غري ضار بالبيئة وأمني االستعمال من بذور املورنكا اوليفريا الستعمال

مت . معاجلة املياهفيها الجل املادة الفّعالة اوليفريا لرتكيز تصنيع بذور املورنكا هذه الدراسة ترّكز على. مياه الشربالتخّلص من الزيوت املوجودة يف البذور اوًال، مث فصل وتنقية املادة الفّعالة باستخدام تقنية التبادل اآليوين كخطوة اوىل

إن أمهية معرفة الوزن اجلزيئي . لتوندا 6500 – 1000حيث كان الوزن اجلزيئي مابني ملعرفة الوزن اجلزيئي للمادة الفّعالةمت معرفة فّعالية املنتج بواسطة . و الجياد احلجم املناسب للفلرت يف عملية الفصل املقرتحة يف هذه الدراسةهللمادة الفّعالة

لنوعية هو أهم عامل للسيطرة ا. الطريقة التقليدية يف معاجلة املياه باستخدام مناذج مياه صناعية وطبيعية من مياه النهرائية واطئة وأقل من . العكرة املتبقية يف املياه بعد املعاجلة وحدات عكرة قياسية 5نتائج فحص املنتج أعطت عكرة

، %98.5، %95.5إزالة العكرة كان بنسبة . للعكرة يف مياه الشرببل منظمة الصحة العاملية كأقصى حد من قاملقررة ا طريقة سهلة . كرة الواطئة واملتوسطة والعالية على التوايلبالنسبة ملياه النهر ذات الع %99.3و طريقة الفلرتة أثبتت إ

فصل الزيوت، إستخالص املادة الفّعالة مبلح كلوريد الصوديوم، مث (املادة الفّعالة باستخدام خطوات قليلة وعملية لفصل للخلطحص هي السرعة الواطئة، والوقت الكايف إن أهم العوامل املؤثرة يف عملية الف). مايكروميرت 0.2الفلرتة حبجم

أوضحت . مت عمل تصميم الجياد أفضل العوامل املؤثرة يف عملية تصفية املياه. وكذلك كمية املادة املنتجة املضافة للماءافة دقيقة، وكمية املادة الفّعالة املض 41,28دورة بالدقيقة، وقت اخللط 40نتائج التصميم إن أحسن سرعة واطئة هي

وّضح املوديل .من هذه النتائج باستخدام املياه الصناعية ومياه النهر ذات العكرة الواطئة حققمت الت. ملغم باللرت 0.69لكل عوامل 0.01إن كل هذه العوامل ذات تأثري قوي يف معاجلة املياه وأعطت إحتمالية أقل من اخلاص بالتصميم

كانت العكرة االولية ملياه النهر .بدون اي إضافات باستخدام مياه النهر %95.1املوديل و إزالة العكرة كان بنسبة كانت سرعة و ملغم باللرت من املخثّر املنتج 0.75باستخدام وحدة عكرة 1.6وحدة للعكرة واليت مت تقليلها اىل 32.4مت استخدام .افة اي مواد كيمياويةتعترب طريقة الفلرتة سهلة والحتتاج اىل إض . دقيقة 41دورة بالدقيقة وملدة 40اخللط

املخثّر بكميات قليلة الزالة العكرة بنسبة عالية وهذا يعترب جناح كبري يف هذه الدراسة اليت توصي باالهتمام واالخذ بنظر نتاجإن ا. يعترب هذا املنتج ذو قيمة إقتصادية ويف نفس الوقت يقلل كلفة معاجلة املياه .االعتبار على تصنيع هذا املنتج

زيت الطبخ، ( كما إن املواد الثانوية املنتجة. للتطور االقتصادي يف ماليزيا ممكن أن يؤدي خدمة لبديل حملياً ا املخثّرالوصول اىل خالصة بان هذا املنتج الينتج ممكن و . هلا فائدة إقتصادية ايضاً )الكاربون املنّشط، العلف احليواين والسماد

.أي خملفات للبيئة

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APPROVAL PAGE

The thesis of Eman N. Ali has been approved by the followings:

_____________________ Suleyman Aremu Muyibi

Supervisor

_____________________ Md. Zahangir Alam

Co Supervisor

_____________________ Hamzah Mohd. Salleh

Co Supervisor

_____________________ Ma’an Fahmi Alkhatib

Internal Examiner

_____________________ Mohammed Saedi Jami

Internal Examiner

_____________________ Fakhru’l-Razi Ahmadun

External Examiner

_____________________ Nasr Eldin Ibrahim A. Hussien

Chairman

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DECLARATION

I hereby declare that the thesis is the result of my own investigations, except where

otherwise stated. I also declare that it has not been previously or concurrently

submitted as a whole for any other degrees at IIUM or other institutions.

Eman N. Ali Signature ------------------------ Date ----------------

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INTERNATIONAL ISLAMIC UNIVERSITY MALAYSIA

DECLARATION OF COPYRIGHT AND AFFIRMATION OF FAIR USE OF UNPUBLISHED

RESEARCH

Copyright © 2010 By Eman N. Ali. All Rights Reserved.

PRODUCTION OF PURIFIED BIOACTIVE COAGULANT FROM MORINGA OLEIFERA FOR PROCESS OPTIMIZATION OF WATER

TREATMENT

No part of this unpublished research may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without prior written permission of the copyright holder except as provided below.

1. Any material contained in or derived from this unpublished research may only be used by others in their writing with due acknowledgement.

2. IIUM or its library will have the right to make and transmit copies

(print or electronic) for institutional and academic purposes.

3. The IIUM library will have the right to make, store in a retrieval system and supply copies of this unpublished research if requested by other universities and research libraries.

Affirmed by Eman N. Ali -------------------------------- ----------------------

Signature Date

vii

ACKNOWLEDGEMENTS

Firstly, praise is to Allah, the Most Gracious and the Most Merciful; from HIM I got the health, the power and the patience to accomplish this study. I wish to express my sincere gratitude and appreciation to the chairman of the supervisory committee, Prof. Dr. Suleyman Aremu Muyibi for his great support, valuable guidance, encouragement and his patience with me throughout this research study period. Also, I would like to thank the other members of the supervisory committee, Associate Prof. Dr. Mohd. Zahangir Alam, Associate Prof. Dr. Hamzah Mohd. Salleh, and Associate Prof. Dr. Mohd Ramlan Mohd. Salleh, for their advice, constructive suggestions, guidance, and co-operation throughout the study period. Also, I appreciate the financial support from Ministry of Science, Technology and Innovation (MOSTI), Malaysia under project IRPA (09-02-08-10002-EAR) headed by Prof. Dr. Suleyman Aremu Muyibi.

I dedicate this work to my beloved late father, my mother, sisters and brothers and their children for their caring and encouragement during this period of struggle. And, special thanks with love goes to my children Saif and Farah for their understanding, caring, patience and the most important, their encouragement to successfully finish this work. Very special thanks to Dr. Farida Yusuf (IIUM) for providing the glass mixer for ion exchange process. Many thanks to Dr. Abdulkarim S.M. and Mr. Wai Kien Tat (Universiti Putra Malaysia), for their great help by providing the Moringa oleifera’s pods and seeds. Thanks to Brother Zanuddin B. Kisman, Puncak Niaga (M) Sdn. Bhd. for providing information about Wangsa Maju Water Treatment Plant. Special thanks to all IIUM staff, lecturers, students, Eng. Zahir Hossain, and Eng. Mohd Raziff Mat Hasan. The author would like to thank Sister Azizah Mohamad Yusof and Sister Rohamah Hashim for their great assistance in many ways during the study period. Thanks to Brothers Aslan, Hafizul, and Anwar who helped me sincerely to complete this study.

Many thanks go to my colleagues and friends who really cared about me finishing this study. Their encouragement and support is highly appreciated.

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TABLE OF CONTENTS

Abstract in English ….….……………………………………………………........ Abstract in Arabic ……………………………………………………………........ Approval Page ……...………………………………………………………….......Declaration ……......……………………………………………….........................Copyright Page …………………………………………………………………....Acknowledgements ……………………………………………………………..…List of Tables ………………………………………………………………….......List of Figures ………………………………………………………………..........List of Abbreviations ……………………………………………………………...

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CHAPTER ONE: INTRODUCTION ………………………………………....... 1.1 Background of study……..……….…………………………................ 1.2 Justification of the research………………………………................... 1.3 Problem statement ………………………………………….................. 1.4 Research objectives……………………………………………............ 1.5 Research Methodology………………………………………………… 1.6 Scope of study….……………………………………………………… 1.7 Thesis organization….………………………………………………… CHAPTER TWO: LITERATURE REVIEW ...……………………………….. 2.1 Introduction…...…………………………..………………………….…

2.2 coagulation of turbid water…………………………………………..... 2.2.1 Water extraction of bioactive constituents from Moringa oleifera…………………………………………………………. 2.2.1.1 Research background on Moringa oleifera as a coagulant 2.2.1.2 Studies on Moringa oleifera as a coagulant…………….. 2.2.1.3 Coagulation process studies…………………………….. 2.2.1.4 Studies on shelled & non-shelled Moringa oleifera…….. 2.2.1.5 Studies on Moringa oleifera composition………………. 2.2.1.6 Studies on combination between Moringa oleifera & alum……………………………………………………… 2.2.1.7 Oil extraction effect on Moringa oleifera coagulation activity……………………………………………….….. 2.2.1.8 Pilot studies for using Moringa oleifera as a coagulant…. 2.2.1.9 Summary of water extraction studies….………………… 2.2.2 Salt extraction of bio-active constituents from Moringa oleifera ………………………………………………………… 2.2.3 Water and salt extraction studies…...………………………….. 2.3 Moringa oleifera tree…………………………………………………… 2.3.1 Moringa oleifera structure and molecular weight……………… 2.3.2 Moringa oleifera as a coagulant/flocculant…….………………. 2.3.3 Moringa oleifera as a hard water softener…………….………..

1 1 3 5 6 7 8 8 10 10 11 11 11 12 13 14 15 16 18 18 19 19 23 24 26 28 29

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2.3.4 Moringa oleifera as a disinfectant……………………………… 2.3.5 Moringa oleifera as a sludge conditioner………………………. 2.3.6 Moringa oleifera for removal of organic and heavy metal from water……………………………………………………………. 2.3.7 Moringa oleifera in waste water treatment…………………….. 2.3.8 Moringa oleifera for producing edible oil……………………… 2.3.9 Moringa oleifera as animals feed and fertilizer………………… 2.3.10 Moringa oleifera for producing activated carbon…………….. 2.3.11 Moringa oleifera as a medicine..……………………………… 2.4 Coagulants used in water treatment industry ………………….............. 2.5 Water treatment process…………………………….............................. 2.6 Cross flow filtration……………………………………………………. 2.6.1 Microfiltration………………......................................................... 2.6.2 Ultrafiltration ……....…………………………………………… 2.7 Optimization……………………………………………………………. 2.8 Summary……………………………………………………………….. CHAPTER THREE: RESEARCH METHODOLOGY………………………. 3.1 Introduction ……………………………………………………………. 3.2 Isolation and purification of flocculating bio-active constituents by chromatography techniques…………………….…………………. 3.2.1 Raw Moringa oleifera preparation.............……………………… 3.2.2 Oil extraction ………………………………..………………….. 3.2.3 Salt extraction of bio-active constituents……..…………………. 3.2.4 Isolation & purification of bio-active constituents from Moringa Oleifera seeds................................................................................ 3.2.4.1 Buffers preparation……………………………………… 3.2.4.2 Preparation of the column………………………………. 3.2.4.3 Loading of the sample to ion exchange column………… 3.2.4.4 Protein assay……………………………………………. 3.2.4.5 Preparation of standard protein assay…………………… 3.2.4.6 Measuring the concentration of bio-active constituents… 3.3 Molecular weight measurement using HPLC………………………….. 3.4 Cross flow filtration method…………………………………………… 3.4.1 Microfiltration…………………………………………………. 3.4.2 Ultrafiltration process………………………………………….. 3.4.3 Coagulation test………………………………………………….. 3.4.3.1 Synthetic water (kaolin suspension) preparation………… 3.4.3.2 Jar test……………………………………………………. 3.4.3.3 Concentration of bio-active constituents……………….. 3.4.3.4 Other tests for treated water…………………………….. 3.4.3.5 Freeze drying……………………………………………. 3.5 Optimization of operating conditions………………………………….. 3.5.1 First step optimization…………………………………………… 3.5.2 Second optimization……………………………………………… 3.5.3 Jar test…………………………………………………………… 3.6 Summary………………………………………………………………..

30 30 31 32 32 33 34 34 35 37 37 38 38 39 40

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48 48 50 50 50 51 51 52 53 54 55 57 57 57 59 59 60 61 62 65 66 67

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CHAPTER FOUR: RESULTS AND DISCUSSION………..………………. 4.1 Introduction ………………………………………………………….. 4.2 Isolation and purification of the flocculating bio-active constituents by chromatography techniques……………………………………….. 4.2.1 Raw Moringa oleifera preparation……...……………………….. 4.2.2 Oil Extraction……………………………………………………. 4.2.3 Salt extraction of bio-active constituents………………………… 4.2.4 Isolation and purification of bio-active constituents from Moringa oleifera seeds by chromatography technique……….. 4.2.5 Detailed study for selected samples………………………….…. 4.2.6 Summary of the findings for the first objective of the study…… 4.3 Evaluation of flocculating bio-active constituents performance and determination the molecular weight……………………………... 4.3.1 Determination of molecular weight by HPLC………………… 4.3.2 Evaluation of coagulation performance by Jar test…………….. 4.3.2.1 Coagulation activity using synthetic water……………. 4.3.2.2 Coagulation activity using river water………………… 4.3.3 Summary of the findings for the second objective of the study. 4.4 Performance efficiency of bioactive constituents processed by cross flow filtration …..…………………………………………………….. 4.4.1 Sample preparation for membrane separation……………….... 4.4.1.1 Microfiltration with 0.45 µm microfiltration cartridge…………………………………………….... 4.4.1.2 Ultrafiltration with 1000 Dalton membrane…………... 4.4.2 Jar test for micro and ultrafiltration process evaluation………. 4.4.3 Different micro and ultrafiltrations used for bio- active constituents separation ………...................................... 4.4.3.1 Jar test for the micro & ultra filtered samples………… 4.4.3.1.1 Residual turbidity tests result…………………. 4.4.3.1.2 Chemical Oxygen Demand tests result.………... 4.4.3.1.3 pH tests result..…………………………………. 4.4.3.1.4 Conductivity tests result………………………. 4.4.3.2 Jar Test for aluminum sulphate (alum)……….…….... 4.4.3.3 Jar Test for aluminum sulphate & processed Moringa oleifera………………………………………………… 4.4.4 Summary of the findings for the third objective of the study…. 4.5 Optimization study of water treatment operating parameters…........... 4.5.1 First step optimization…… …………………………………… 4.5.1.1 Regression model equation…………………………..... 4.5.2 Second optimization…………………………………………… 4.5.2.1 Regression model equation……………………………. 4.5.3 Verification of the model……………………………………… 4.5.4 Summary of the findings for the fourth objective of the study... 4.6 Summary …………………...………………………………………... CHAPTER FIVE: CONCLUSIONS AND RECOMMENDATIONS………. 5.1 Conclusion……………………………………..…..………………….. 5.2 Novelties of the study…………………………….……………………

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5.3 Potential benefits……………………………………………………... 5.4 Recommendations ...…………………………………………………. BIBLIOGRAPHY……………………………………………………..…………. PUBLICATIONS……………………………………………………..………….. APPENDICES…………………………………………………………….………

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LIST OF TABLES

Table No. Page No.

3.1 3.2 3.3 3.4 3.5 3.6 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 4.11 4.12 4.13 4.14

Range of levels for parameters used in jar test (first optimization) Design summary (first optimization) Five factors design Range of levels for parameters used in jar test (second optimization) Design summary (second optimization) Three factors design

Protein concentration for samples from Figure 4.6 HPLC measurements (retention time for the standards) HPLC results for 11 points selected in Figure 4.7 Turbidity removal percentage for 11 selected samples Best residual turbidity and volume of water to be treated with different peaks Jar test results for river water of low, medium, and high initial turbidity

Ultrafiltration jar test Protein concentration for the processed Moringa oleifera samples Jar test using river water sample treated with alum Comparison between alum and processed Moringa oleifera in water treatment Analysis of variance for regression model (first optimization) Regression value and standard deviation (first optimization) Solutions for regression model (first optimization) Design and experimental results of response (residual turbidity)

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4.15 4.16 4.17 4.18

Analysis of variance for regression model (second optimization) Regression value and standard deviation (second optimization) Validation of the residual turbidity using synthetic water Validation of the residual turbidity using river water

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LIST OF FIGURES

Figure No. Page No.

2.1 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 4.1 4.2

Polysaccharide units Flow chart of processed Moringa oleifera seeds Moringa oleifera Tree Moringa oleifera pods and seeds Sieved Moringa oleifera seed Electro thermal soxhlet for oil extraction Moringa oleifera seeds and the extracted oil

Ion exchange process Ion exchange product of bio-active constituents and the raw seeds High Performance Liquid Chromatography (HPLC) QuixStand benchtop system with peristaltic pump Different applications for micro and ultrafiltration process Flocculator and turbidimeter used for jar test

HACH DR 5000 equipment and COD Heater Conductivity meter and pH meter Freeze dried product with raw seeds Sungai Pusu at IIUM Samples of raw seeds, oil extract, seeds cake, processed sample, andfreeze dried sample Elution of the fractions with different NaCl molarities Residual turbidity by using the eluted bio-active constituents with 0.4 M NaCl

26

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4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 4.11 4.12 4.13 4.14 4.15 4.16 4.17 4.18 4.19 4.20 4.21 4.22

Residual turbidity by using the eluted bio-active constituents with 0.6 M NaCl Residual turbidity by using the eluted bio-active constituents with 0.8 M NaCl Residual turbidity by using the eluted bio-active constituents with 1.0 M NaCl Elution of fractions using 1 M NaCl with three main peaks Eleven samples of the detailed study Residual turbidity results by adding different dosages from 11 samplesto synthetic water. Low turbidity river water samples treated with processed Moringa oleifera Medium turbidity river water samples treated with processed Moringa oleifera High turbidity river water samples treated with processed Moringa oleifera Change of permeate flux over time using ultrafiltration Residual turbidity for microfiltration with 0.45µm Residual turbidity for microfiltration with 0.45µm followed by 1 kDa(Retentate) Residual turbidity for microfiltration with 0.45µm followed by 1 kDa(Permeate) Residual turbidity results for samples 1-7 COD results for samples 1-7 pH values results for samples 1-7 Conductivity results for samples 1-7 Residual turbidity for river water samples of low turbidity using alum COD for river water samples of low turbidity using alum pH for river water samples of low turbidity using alum

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4.23 4.24 4.25 4.26 4.27 4.28 4.29

Conductivity for river water samples of low turbidity using alum Jar test results for centre points Regression value of actual and predicted residual turbidity (firstoptimization) Regression value of actual and predicted residual turbidity (secondoptimization) The interaction between low speed and mixing time The interaction between low speed and dose The interaction between low speed mixing time and dose

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LIST OF ABBREVIATIONS Alum Aluminium Sulphate BSA CCD COD Da DOC DOE HPLC kDa MO MW NTU pI POME RSM USEPA WHO

Bovine Serum Albumin Central Composite Design Chemical Oxygen Demand Dalton Dissolved Organic Carbon Design Of Experiments High Performance Liquid Chromatography Kilo Dalton Moringa Oleifera Molecular Weight Nephelometric Turbidity Units Isoelectric Point Palm Oil Mill Effluent Response Surface Methodology United States Environmental Protection Agency World Health Organization

1

CHAPTER ONE

INTRODUCTION 1.1 BACKGROUND OF STUDY

Developing countries are facing potable water supply problems because of inadequate

financial resources. The cost of water treatment is increasing and the quality of river

water is not stable due to suspended and colloidal particle load caused by land

development and high storm runoff during rainy season, such is experienced in a

country like Malaysia. During the rainy season, turbidity level increases and the need

for water treatment chemicals increase as well, which leads to high cost of treatment

which are unsustainable by water treatment companies. As a result, drinking water

that reaches the consumer is not properly treated. It is of great importance to find a

natural coagulant alternative for water treatment. Moringa oleifera is the best natural

coagulant discovered so far that can replace aaluminium sulphate (alum), which is

used widely for water treatment around the world. In addition, there is the fear that

aluminium may induce Alzheimer’s disease, and it has been also indicated to be a

causative agent in neurological diseases such as pre-senile dementia. Using alum as

well as other metallic salt coagulants produces large sludge volumes which are also

non-biodegradable (Muyibi, 1995).

Water supply and sanitation are basic needs. It is untenable and unbelievable

that waterborne diseases still kill on average 25,000 people every day in developing

countries while millions suffer the debilitating effects of these diseases (Kalbamatten

& Burns, 1983). Paradoxically, while a few privileged people flush toilets with about

60,000L of clean water to dispose of only 600 L of body waste per day, the women

2

and children in rural areas spend about 6 or more hours every day to fetch a few liters

of polluted water about 10 km away from their households (Hussain, 1981). The cost

in human suffering is staggering, with attendant effects of waterborne diseases like

typhoid, yellow fever, diarrhea, and schistosomiasis being only a few of the infections

introduced or spread by inadequate and polluted water supplies and poor sanitation

(Muyibi, 1992). The amount of resources available to living creatures are limited, the

human beings should use these resources with limited waste, attention to non-human

life forms, and concern for land, air, and water (Muyibi, 2000). Human being is an

integral part of nature and our interaction with the fragile ecological system which

surrounds us is of major importance to our continued survival. This calls for a re-

appraisal of the functional relationships that exist between the environment, ecology

and man (Muyibi, 1989).

About 75% of the present world population lives in developing countries. A

large proportion lives in rural areas and conventionally treated potable water is

generally unavailable in such places. Even though urban centres in these countries

have centralized facilities for conventional drinking water treatment, the quality of

such water is often suspected, either because of improper treatment or contamination

during storage. It has been estimated that of the 1.2 billion people who are without

safe drinking water, approximately 80% live in relatively small rural communities.

For a riparian population, during the rainy season, surface water sources are highly

turbid and on occasions contain bacterial concentrations similar to dilute raw sewage.

Consumption of unsafe water is known to be responsible for a large proportion of

diseases in these countries (Muyibi, 1995).

At least 1.8 million people die every year mostly in developing countries from

diseases, including diarrhea and cholera; 90% are children under the age of five. The

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World Health Organization (WHO) estimates that 88% of diarrhea disease is

attributed to unsafe drinking-water supply and inadequate sanitation and hygiene.

Studies have indicated that an improved drinking-water supply reduces diarrhea

morbidity by 6% to 25% and improved sanitation reduces it by 32%.

About 1.2 billion people still lack safe drinking water and more than 6 million

children die from diarrhea in developing countries every year. In many parts of the

world, river water that can be highly turbid is used for drinking purposes. The limit of

residual turbidity in drinking water was set by WHO as a guideline value at 5

Nephelometric Turbidity Units (NTU) (McConnachie et al., 1999) as safe limit. As

identified by the United States Environmental Protection Agency (EPA), turbidity is a

measure of the cloudiness of water; it is used to indicate water quality and filtration

effectiveness. Higher turbidity levels are often associated with higher levels of

disease-causing micro organisms such as viruses, parasites and some bacteria. These

organisms can cause symptoms such as nausea, cramps, diarrhea, and associated

headaches (U.S. Environmental Protection Agency, 2008).

Water-borne infectious diseases caused by viruses, bacteria, protozoa and other

micro organisms are associated with outbreaks of and background rates of diseases in

developed and developing countries worldwide (WHO, 2008). Seventy five percent of

the population in third world countries still live without any kind of sanitation facility

while about 60% is without safe drinking water (Muyibi, 1992).

1.2 JUSTIFICATION OF THE RESEARCH

Naturally occurring coagulants are usually presumed safe for human health. Earlier

studies have found the Moringa oleifera seeds are non-toxic, and recommended its use

as coagulant in developing countries. Encouraged by the results of these studies, many

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developing countries have turned to use this plant as a viable coagulant in water and

wastewater treatment on a small scale (Ndabigengesere et al., 1995). Some studies on

natural coagulants have been carried out and various natural coagulants were

produced or extracted from micro organisms, animals or plants (Kawamura, 1991; Lee

et al., 1995; Ganjidoust et al., 1997). Natural coagulants from vegetable and mineral

origins were used for water treatment before the advent of chemical salts, but these

have not been able to compete effectively because the scientific understanding of their

effectiveness and mechanism of action is still limited. Thus far, use of natural

coagulants has been discouraged without full scientific evaluation. They have

succumbed progressively under modernization and survived only in remote areas of

some developing countries. Recently however, there has been a resurgence of interest

in natural coagulants for water treatment in developing countries (Ndabigengesere &

Narasiah, 1998).

Natural coagulants from plant families such as: Capparidaceae and

Papilionaceae have been traditionally used to clean water in private households.

Branches and bark of Boscia senegalensis of the Capparidaceae family for example,

have been added to the water for purification. In Egypt and northern Sudan, seeds of

Papilioaceae including the genera Phaseolus (various bean cultivars), Pisum (peas),

Arachis (peanuts), and Lupinus (lupines) are used, although their purifying effect is

low. More efficient are plants of the genus Vicia (field bean) which have been applied

for water cleaning in Bolivia (Gassenschmidt et al., 1995). Most research has been

conducted on Moringa oleifera for water treatment. Moringa oleifera is one of the

most wide spread plant species that grows quickly at low altitudes in the tropical belt,

including arid zones. It can grow on medium soils having relatively low humidity

(Ndabigengesere et al., 1995).

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In the Sudan, the crude extract from the Moringa oleifera seeds is used instead

of alum by rural women to treat highly turbid Nile water, because of a traditional fear

of alum which is believed to cause gastro-intestinal disturbances, with the resultant

fear of possible miscarriages for pregnant women (Muyibi, 1994).

1.3 PROBLEM STATEMENT

Safe drinking water is essential to the health and welfare of a community and water

from all sources must have some form of purification before consumption. Various

methods are used to make water safe for the consumer. The method employed

depends on the character of the raw water. One of the problems with the treatment of

surface water is the large seasonal variation in turbidity (McConnachie et al., 1999).

Current operational procedures at many treatment works in developing countries are

based on arbitrary guidelines, particularly in relation to the chemicals dose. In

addition, there is also the problem of an inadequate number of skilled workers and

inadequate laboratory facilities to monitor process performances required to operate

the treatment plants (Muyibi, 1998). Water treatment companies in developing

countries face a myriad of problems. Some of these include; high cost of water

treatment chemicals which constitute between 35% to 70% of recurrent expenditure,

inadequate supply of chemicals for water treatment, inadequate funding, low revenue

base, poor operational and maintenance schedules, adoption of inappropriate

technology. The supply of inadequate water and poor quality water, and the frequent

breakdown of plant and equipment are due to above reasons (Muyibi, 1995).

Therefore, it is so important to think seriously about this problem and work towards

attempt solving it by understanding the processing, materials used, availability, and

how far the economy of developing countries can bear the costs of the chemicals

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needed for water processing, including understanding the alternatives to existing water

treatment chemicals.

In Malaysia, alum is used for water treatment for the coagulation- flocculation

process. The cost of alum was RM 1400/ tonne in the year 2008 which is produced

locally. The calcium carbonate (lime) for pH adjustment is added to the water

treatment process, which is an extra cost for water treatment companies. Using alum

as well as other metallic salt coagulants produces large sludge volumes. The sludge is

non-biodegradable, which increases water pollution.

The consumption of alum is very high in water treatment in Malaysia. The

main concern in this study is low turbidity water which was difficult to treat according

to other researchers presentations. The ideal plant for low turbidity water treatment in

Malaysia is Wangsa Maju Water Treatment Plant (Puncak Niaga (M) Sdn Bhd), the

process flow sheet is given in (Appendix A). The plant is working to treat the low

turbid water with initial turbidity of 30 NTU or less. The process depends on using

several additives to get residual turbidity of less that 5 NTU. The dose of alum used is

between 13-18 mg/L, chlorine is added with an amount of 3.55 Kg/hour, and for post

chlorination 5.5 Kg/hour, besides adding fluoride 0.5-0.6 mg/L, lime CaCO3 for pH

adjustment, and (Chamfloc 151) sludge dewatering with an amount of 3% w/w as

used in water treatment plant. Some chemicals are local and some are imported

(Personal communications, 2009). Therefore, this study focuses on the treatment of

water with low turbidity.

1.4 RESEARCH OBJECTIVES

The general objective is to develop an efficient processing technique for Moringa

oleifera seeds for use in water treatment for potable use.

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Specific objectives are as follows:

i) To isolate and purify the flocculating and non-flocculating bio-active

constituents in Moringa oleifera seeds by chromatography techniques and

to estimate the yield using the protein assay method.

ii) To evaluate the performance of flocculating bio-active constituents in

turbidity removal from turbid water using conventional jar test methods,

and to determine the molecular weight.

iii) To purify the bio-active constituents by cross flow filtration (micro and

ultra filtration) and comparison between the two methods depending on

the conventional jar test results.

iv) To optimize the operating conditions (rapid mixing speed and time, slow

mixing speed and time, processed Moringa oleifera dosage) of the

flocculating bio-active constituents in coagulation of turbid water for

potable use.

1.5 RESEARCH METHODOLOGY

This study is confined within the scope of work starting from sample collection to the

production of processed Moringa oleifera as a natural coagulant and testing it for

water treatment. It is described briefly as follows:

i. Collection of Moringa oleifera pods. Removing the seed coat and wings.

Grinding of the seeds and sieving the powder < 250 µm.

ii. Oil extraction from Moringa oleifera seeds to remove the organic

compounds.

iii. Extraction of bioactive constituents by NaCl.