SYNTHESIS OF ACTIVATED CARBON VIA MICROWAVE HEATING FOR DYES REMOVAL

SYNTHESIS OF ACTIVATED CARBON VIA MICROWAVE HEATING FOR DYES REMOVAL

SITI RUQAYYAH BINTI AB HAMID

UNIVERSITI SAINS MALAYSIA

2018

SYNTHESIS OF ACTIVATED CARBON VIA MICROWAVE HEATING FOR DYES REMOVAL

by

SITI RUQAYYAH BINTI AB HAMID

Thesis submitted in fulfilment of the requirement for the degree of

Master of Science

September 2018

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ACKNOWLEDGEMENT

In the name of Allah, the Most Beneficent and the Most Merciful. All praises to Allah the Almighty for blessing me with the opportunity to start this beautiful journey and motivation to complete the dissertation. I would like to express my deepest gratitude to both of my beloved parents, Abdul Hamid Awang Suri and Marilah Abdullah, my beloved husband, Wan Mohd Radhi Wan Mohd Raimi as well as my other family members for their continuous love and support. My appreciation goes to my supervisor, Professor Dr. Mohd Azmier Ahmad who had lending me great research experience along my study. His understanding, vast knowledge and personal guidance have provided me with good basis in carrying out the experiment and writing this thesis.

I would like to thank all the technicians and postgraduate students of School of Chemical Engineering especially Mohd Firdaus Yusop for their kindness assistance, professional advice and guidance along completing my thesis. I would like to express gratitude to Ministry of Higher Education for MyBrain 15 and Universiti Sains Malaysia under grant schemes (Grant no. 1001/CKT/870023 and 1002/PJKIMIA/910313) for research associated with the Solid Waste Management Cluster and Delivering Excellence, respectively for funding this project. Last but not least, those who have directly and indirectly contributed to the accomplishment of this project. Thank you very much.

Siti Ruqayyah binti Ab Hamid September 2018

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TABLE OF CONTENTS

Page

ACKNOWLEDGEMENT ii

TABLE OF CONTENTS iii

LIST OF TABLES vii

LIST OF FIGURES x

LIST OF ABBREVIATIONS xiv

LIST OF SYMBOLS xv

ABSTRAK xvii

ABSTRACT xix

CHAPTER ONE INTRODUCTION

1.1 Dyes 1

1.2 Agrowaste based activated carbon 3

1.3 Problem statement 5

1.4 Research objectives 6

1.5 Scopes of study 7

1.6 Organization of thesis 8

CHAPTER TWO LITERATURE REVIEW

2.1 Dye removal methods 9

2.2 Adsorption process 11

2.3 Activated carbon 13

2.4 AC production 15

2.5 Microwave irradiation 17

2.6 Adsorption isotherm 18

2.6.1 Langmuir isotherm 22

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2.6.2 Freundlich isotherm 23

2.6.3 Temkin isotherm 24

2.6.4 Dubinin-Radushkevich isotherm 25

2.7 Adsorption kinetics 26

2.7.1 Pseudo-first order kinetic model 26

2.7.2 Pseudo-second order kinetic model 27

2.8 Adsorption diffusion mechanism 28

2.8.1 Intraparticle diffusion mechanism model 29

2.8.2 Boyd plot diffusion mechanism model 30

2.9 Adsorption thermodynamic parameters 30

CHAPTER THREE MATERIALS AND METHOD

3.1 Experimental activities 33

3.2 Materials 34

3.2.1 AC preparation 36

3.2.2 Batch adsorption and analysis system 37

3.2.3 Characterization system 38

3.3 Experimental procedure 38

3.3.1 Preparation of AC 39

3.3.2 Preparation of adsorbate solution 40

3.3.3 Sample analysis system 41

3.3.4 Experimental design for AC preparation 41 3.3.5 Development of regression model statistical analysis 43 3.3.6 Batch adsorption equilibrium studies 44

3.3.6 (a) Effect of contact time and initial dye

concentration 46

3.3.6 (b) Effect of solution temperature 46

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3.3.6 (c) Effect of solution pH 46

3.3.6 (d) Adsorption isotherm model 47 3.3.7 Batch adsorption kinetics and mechanism studies 47

3.3.8 Adsorption thermodynamic studies 48

CHAPTER FOUR RESULTS AND DISCUSSION

4.1 Experimental design 49

4.1.1 Regression model development on DSAC 49 4.1.2 Three-dimensional response surface of DSAC 56 4.1.3 Regression model development on JSAC 58 4.1.4 Three-dimensional response surface of JSAC 64 4.1.5 Optimization of operating parameters 66

4.2 Characterization of ACs 68

4.2.1 Surface area and pore characteristics 68

4.2.2 Proximate and elemental analysis 69

4.2.3 Surface morphology 71

4.2.4 Surface chemistry 73

4.3 Batch adsorption studies 75

4.3.1 Batch equilibrium studies 75

4.3.1(a) Effect of contact time and MB dye initial

concentration 76

4.3.1(b) Effect of contact time and MY dye initial

concentration 79

4.3.1(c) Effect of solution temperature 85

4.3.1(d) Effect of solution pH 87

4.3.2 Isotherm studies 89

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4.3.2 (a) MB adsorption isotherms 89

4.3.2 (b) MB adsorption isotherms 95

4.3.3 Kinetic studies 99

4.3.3 (a) MB adsorption kinetic 99

4.3.3 (b) MY adsorption kinetic 104

4.3.4 Mechanism studies 109

4.3.4 (a) MB diffusion mechanism 109

4.3.4 (b) MY diffusion mechanism 114

4.3.5 Thermodynamic studies 118

CHAPTER FIVE CONCLUSIONS AND RECOMMENDATIONS

5.1 Conclusions 120

5.2 Recommendations 122

REFERENCES 123

APPENDICES

Appendix A :Calibration curve for MB and MY dyes Appendix B : Plots of adsorption uptakes versus time Appendix C: Plots of percentage removal versus time

Appendix D : Amount of dyes adsorbed and percent removal Appendix E : Parameters of isotherms

Appendix F : Plots of separation factor versus adsorbate initial concentration Appendix G : Kinetic Parameters

Appendix H: Parameters of intraparticle diffusion Appendix I : Boyd plots

Appendix J : Thermodynamic calculation

LIST OF PUBLICATIONS

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LIST OF TABLES

Page Table 2.1 Differences between physisorption and chemisorption 12

Table 2.2 Previous works of AC derived from agrowastes 13

Table 2.3 Types of physical form of AC (Hadi et al., 2015) 15

Table 2.4 Stages occur during carbonization process (Wilk et al., 2016) 16

Table 2.5 Summary of findings for previous works using microwave heating activation

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Table 2.6 The differences between conventional furnace and microwave irradiation (Alslaibi et al., 2013)

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Table 3.1 Properties of MB dye 34

Table 3.2 Properties of MY dye 35

Table 3.3 List of chemicals and gases 35

Table 3.4 Experimental design matrix for AC preparation 42

Table 4.1 Experimental design matrix for preparation of DSAC 51

Table 4.2 ANOVA results for MB removal by DSAC 54

Table 4.3 ANOVA results for MY removal by DSAC 55

Table 4.4 ANOVA results for DSAC’s yield 55

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Table 4.5 Experimental design matrix for preparation of JSAC 61

Table 4.6 ANOVA results for JSAC’s yield 64

Table 4.7 Model validation for ACs prepared for MB removal 67

Table 4.8 Model validation for ACs prepared for MY removal 67

Table 4.9 Surface area and pore characteristics of the samples 69

Table 4.10 Proximate and elemental analysis for samples 70

Table 4.11 Amount of dyes adsorbed, qt and percent removal of MB and MY on DSAC and JSAC at 30°C

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Table 4.12 Parameters of isotherms for adsorption of MB dye by MB- DSAC and MY-JSAC at 30°C

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Table 4.13 Parameters of isotherms for adsorption of MY dye by MY- DSAC and MY-JSAC at 30°C

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Table 4.14 Kinetic parameters for MB-DSAC and MB-JSAC systems at 30°C

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Table 4.15 Kinetic parameters for MY-DSAC and MY-JSAC systems at 30°C

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Table 4.16 Intraparticle diffusion model constants for adsorption of MB onto MB-DSAC and MB-JSAC at 30°C

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Table 4.17 Intraparticle diffusion model constants for adsorption of MY onto MY-DSAC and MY-JSAC at 30°C

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Table 4.18 Thermodynamic parameters for MB and MY dyes adsorption onto optimized ACs

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LIST OF FIGURES

Page Figure 1.1 The image of (a) durian seed and (b) jackfruit seed 5 Figure 2.1 Schematic diagram of adsorption process (Heibati et al.,

2014)

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Figure 2.2 Types of pore in AC 14

Figure 2.3 Thermal gradient development between (a) conventional heating and (b) microwave irradiation technique (Wu et al., 2014)

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Figure 2.4 Three stages of adsorption mechanism involved in adsorption process (Weng et al., 2009)

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Figure 3.1 Schematic flow diagram of experimental activities 33 Figure 3.2 Schematic diagram of char preparation unit 36 Figure 3.3 Schematic diagram of microwave irradiation experimental

setup

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Figure 3.4 Design layout for CCD (Halim, 2008) 43

Figure 4.1 Plot of predicted versus actual experimental values for (a) MB removal, (b) MY removal and (c) DSAC’s yield

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Figure 4.2 Three-dimensional response plot for (a) MB removal (effect of radiation power and IR, radiation time = 6min), (b) MY removal (effect of radiation power and IR, radiation time = 6min) and (c) DSAC’s yield (effect of radiation power and radiation time, IR = 1.25)

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Figure 4.3 Plot of predicted versus actual experimental values for (a) MB removal, (b) MY removal and (c) JSAC’s yield

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Figure 4.4 Three-dimensional response plot for (a) MB removal (effect of radiation power and IR, radiation time = 6min), (b) MY removal (effect of radiation power and IR, radiation time = 6min) and (c) JSAC’s yield (effect of radiation power and radiation time, IR = 1.25)

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Figure 4.5 SEM micrographs of (a) DS and (b) DSAC (magnification 500x)

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Figure 4.6 SEM micrographs of (a) JS and (b) JSAC (magnification 500x)

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Figure 4.7 FTIR spectrums for (a) DS and (b) DSAC 74

Figure 4.8 FTIR spectrums for (a) JS and (b) JSAC 75 Figure 4.9 MB adsorption uptake versus adsorption time at various

initial concentrations on (a) DSAC and (b) JSAC at 30°C

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Figure 4.10 MB percentage removal versus adsorption time at various initial concentrations on (a) DSAC and (b) JSAC at 30°C

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Figure 4.11 MY adsorption uptake versus adsorption time at various initial concentrations on (a) DSAC and (b) JSAC at 30°C

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Figure 4.12 MY percentage removal versus adsorption time at various initial concentrations on (a) DSAC and (b) JSAC at 30°C

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Figure 4.13 Effect of solution temperature on MB adsorption capacity MB-DSAC and MB-JSAC systems

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Figure 4.14 Effect of solution temperature on MY adsorption capacity MY-DSAC and MY-JSAC systems

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Figure 4.15 Effect of initial solution pH on MB removal by MB-DSAC and MB-JSAC

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Figure 4.16 Effect of initial solution pH on MB removal by MY-DSAC and MY-JSAC

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Figure 4.17 Plots of (a) Langmuir, (b) Freundlich, (c) Temkin and (d) Dubinin- Radushkevich for MB adsorption onto MB-DSAC at 30, 45 and 60°C

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Figure 4.18 Plots of (a) Langmuir, (b) Freundlich, (c) Temkin and (d) Dubinin-Radushkevich for MB adsorption onto MB-JSAC at 30, 45 and 60°C

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Figure 4.19 Plots of separation factor, R_L versus MB initial concentration for MB-DSAC and MB-JSAC at 30°C

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Figure 4.20 Plots of (a) Langmuir, (b) Freundlich, (c) Temkin and (d) Dubinin-Radushkevich for MY adsorption onto MY-DSAC at 30, 45 and 60°C

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Figure 4.21 Plots of (a) Langmuir, (b) Freundlich, (c) Temkin and (d) Dubinin-Radushkevich for MY adsorption onto MY-JSAC at 30, 45 and 60°C

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Figure 4.22 Plots of separation factor, RL versus MB initial concentration for MB-DSAC and MB-JSAC at 30°C

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Figure 4.23 Linearized plots of pseudo-first order kinetic model for (a) MB-DSAC and (b) MB-JSAC systems at 30°C

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Figure 4.24 Linearized plots of pseudo-second order kinetic model for (a) MB-DSAC and (b) MB-JSAC systems at 30°C

102

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Figure 4.25 Linearized plots of pseudo-first order kinetic model for (a) MY-DSAC and (b) MY-JSAC systems at 30°C

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Figure 4.26 Linearized plots of pseudo-second order kinetic model for (a) MY-DSAC and (b) MY-JSAC systems at 30°C

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Figure 4.27 Plots of intraparticle diffusion model for MB adsorption by (a) MB-DSAC and (b) MB-JSAC at 30°C

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Figure 4.28 Boyd plots for MB adsorption onto (a) MB-DSAC and (b) MB-JSAC at 30°C

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Figure 4.29 Plots of intraparticle diffusion model for MY adsorption by (a) MY-DSAC and (b) MY-JSAC

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Figure 4.30 Boyd plots for MY adsorption onto (a) MY-DSAC and (b) MY-JSAC at 30°C

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LIST OF ABBREVIATIONS

AC Activated Carbon

ANOVA Analysis of Variance

BET Brunauer–Emmett–Teller

CCD Central Composite Design

DS Durian seed

DSAC Durian seed based activated carbon FTIR Fourier Transform Infrared

IR Imprenation ratio

IUPAC International Union of Pure and Applied Chemistry

JS Jackfruit seed

JSAC Jackfruit seed based activated carbon

MB Methylene blue

MY Metanil Yellow

rpm Rotation per minute

RSM Response surface methodology SEM Scanning electron microscopy

STA Simultaneous thermogravimetric analyzer

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LIST OF SYMBOLS

Symbol Unit

A Arrhenius factor -

A_i Measured absorbance for component i -

AT Constant for Temkin isotherm L/mg

𝑏𝑐 Path length of the cell cm

b_T Constant for Temkin isotherm L/mg

Bt Constant for Boyd model -

C Solute/outlet concentration mg/L

Ce Concentration of adsorbate at equilibrium mg/L

Ci Constant for Intraparticle diffusion model mg/g

C_t Concentration of adsorbate at time, t mg/L

Co Initial adsorbate concentration mg/L

D_p Average pore diameter nm

Ea Arrhenius activation energy of adsorption kJ/mol

F Fraction of solute adsorbed for Boyd model -

K_F Adsorption or distribution coefficient for Freundlich isotherm

mg/g (L/mg)^1/n

KL Rate of adsorption for Langmuir isotherm L/mg

k_pi Adsorption rate constant for intraparticle diffusion model mg/g h^1/2 k1 Adsorption rate constant for pseudo-first-order L/min k2 Adsorption rate constant for pseudo-second-order g/mg h

M1 Concentration of stock solution mg/L

M² Concentration of desired adsorbate solution mg/L

N Total number of experiments required/data point -

nF Constant for Freundlich isotherm -

Q_o Adsorption capacity for Langmuir isotherm mg/g

Qm Maximum adsorption capacity of adsorbent mg/g

Q_DR Maximum adsorption capacity of adsorbent mg/g

qe Amount of adsorbate adsorbed per unit mass of adsorbent at equilibrium

mg/g q_t Amount of adsorbate adsorbed per unit mass of adsorbent mg/g

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qt, cal Calculated adsorption uptake at time, t mg/g

q_{t, exp} Experimental adsorption uptake at time, t mg/g

R Universal gas constant Jol/mol K

RL Separation factor -

R² Correlation coefficient -

SBET BET surface area m²/g

V Volume of the solution L

Vmeso Mesopore volume cm³/g

VT Total pore volume cm³/g

W Mass of adsorbent g

wc Dry weight of prepared activated carbon g

w_o Dry weight of precursor g

X Activated carbon preparation variable -

Y Predicted response -

ΔG^o Changes in standard free energy kJ/mol

ΔH^o Changes in standard enthalpy kJ/mol

Δqt Normalized standard deviation %

ΔS^o Changes in standard entropy kJ/mol

Greek letters

𝜀𝜆 Molar absorptivity coefficient of solute at wavelength -

λ Wavelength nm

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SINTESIS KARBON TERAKTIF MENGGUNAKAN PEMANASAN GELOMBANG MIKRO UNTUK PENYINGKIRAN PENCELUP

ABSTRAK

Metilena biru (MB) sebagai pencelup bes dan metanil kuning (MY) sebagai pencelup acid larut di dalam air serta masing-masing menghasilkan ion positif dan ion negatif. Ion-ion ini tertarik kepada bahagian polar pada molekul air secara elektrostatik, lalu mengakibatkan pencelup-pencelup MB dan MY sukar untuk disingkirkan. Oleh itu, kajian ini berusaha untuk menghasilkan karbon teraktif (AC) berasaskan biji durian dan biji nangka untuk menyingkirkan MB dan MY daripada larutan akuas. Karbon teraktif ini dihasilkan melalui teknik pemanasan gelombang mikro bersama pengaktifan fizikimia menggunakan kalium hidroksida (KOH) dan penggasan karbon dioksida (CO₂). Kesan faktor-faktor penyediaan karbon teraktif (kuasa radiasi, masa radiasi dan nisbah impregnasi, (IR)), telah dioptimakan dengan menggunakan metodologi permukaan sambutan (RSM) untuk menghasilkan nilai respon yang maksimum (penyingkiran MB, penyingkiran MY dan hasilan karbon teraktif). Karbon teraktif yang di hasilkan didapati mengandungi luas permukaan Bruneaur-Emmet-Teller (BET) dan peratusan karbon tetap yang tinggi iaitu 852.30m²/g dan 78.51% untuk karbon teraktif daripada biji durian (DSAC) manakala untuk karbon teraktif daripada biji nangka (JSAC) ialah 715.29m²/g dan 73.94%. Kesan faktor-faktor penyediaan yang optimum ditentukan menjadi (330W, 4.49min dan 0.97 dengan 79.67% penyingkiran MB dan 23.60% hasilan), (355W, 4.15min dan 0.58 dengan 77.68% penyingkiran MB dan 24.40% hasilan), (340W, 4.44min dan 0.94 dengan 78.24% penyingkiran MY dan 23.51% hasilan)

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dan (370W, 4.10min dan 0.78 dengan 77.24% penyingkiran MY dan 23.67%

hasilan) masing-masing untuk system-sistem MB-DSAC, MB-JSAC, MY-DSAC dan MY-JSAC. Kajian garis sesuhu mendapati semua sistem pencelup-penjerap yang dikaji mengikuti model Freundlich manakala kajian kinetik mendapati semua sistem mengikuti model kinetik pseudo-tertib kedua. Kajian mekanisme mendapati semua proses penjerapan dikawal oleh mekanisme resapan filem. Kajian termodinamik mendapati semua sistem penjerapan adalah eksotermik secara semulajadi, rawak dan dikawal oleh proses penjerapan fizikal.

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SYNTHESIS OF ACTIVATED CARBON VIA MICROWAVE HEATING FOR DYES REMOVAL

ABSTRACT

Methylene blue, (MB) as basic dye and metanil yellow (MY) as acid dye dissolved in water to produce negative and positive ions respectively. These ions were electrostatically attracted to the polar side of water molecules, thus making MB and MY difficult to be removed. Therefore, an effort was made to produce activated carbon (AC) from durian seed and jackfruit seed for MB and MY dyes removal from aqueous solution. These ACs were produced by employing microwave irradiation technique as heat treatment and physicochemical activation via potassium hydroxide (KOH) chemical treatment and carbon dioxide (CO2) gasification treatment. The preparation conditions of these ACs (radiation power, radiation time and impregnation ratio, (IR)) were optimized with the help of response surface methodology (RSM) in order to produce maximum value of responses (MB removal, MY removal, and AC’s yield). Durian seed based AC (DSAC) and jackfruit based AC (JSAC) prepared were found to pose relatively high Bruneaur-Emmet-Teller (BET) surface area and fixed carbon percentage which were (852.30m²/g and 78.51%) and (715.29m²/g and 73.94%) respectively. Optimum preparation conditions were determined to be (330W, 4.49min and 0.97 with 79.67% of MB removal and 23.60% of yield), (355W, 4.15min and 0.58 with 77.68% of MB removal and 24.40% of yield), (340W, 4.44min and 0.94 with 78.24% of MY removal and 23.51% of yield ) and (370W, 4.10min and 0.78 with 77.24% of MY removal and 23.67% of yield) for MB-DSAC, MB-JSAC, MY-DSAC and MY-JSAC

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systems respectively. Isotherm studies revealed that all adsorbate-adsorbent systems were best described by Freundlich model whereas kinetic studies revealed that all systems followed pseudo-second order kinetic model. Mechanism studies conducted found that the rate limiting step in adsorption process of all systems were contributed by film diffusion. Thermodynamic studies confirmed that all adsorption systems were exothermic in nature, spontaneous and governed by physisorption.

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CHAPTER ONE INTRODUCTION

This chapter highlights the characteristics of dyes and their threat to the environment together with the importance to use agrowaste as precursor for activated carbon (AC) production. Problem statements, research objectives, scopes of study and organization of thesis are also presented.

1.1 Dyes

The advancement in textile industry is driven by remarkable demand for colourful fabrics. Although this is something positive to the development of economy for the country, a concern had arisen on the extensive use of chemicals in this industry especially synthetic dye. Other industries that utilize dyes in a large scale include rubber, paper, plastics, cosmetics, leather and food (Moreira et al., 2017). Synthetic dyes can be defined as substances that are produced to have two chemical groups attached to its molecule namely, chromopore and auxochromes.

Chromopore provides the colour identity to the dyes while auxochromes play a role in influencing the dyes’ binding properties onto fabrics. The amount of dyes that being produced yearly is 700,000 tons with more than 10,000 of dyes’ variations (Daoud et al., 2017). Out of these, 30% are estimated to escape from conventional wastewater treatment system and enter the environment during the dyeing process.

Dyes that escaped into the environment are able to exist for a very long time due to their non-biodegradable property besides being highly stable towards heat, light and oxidizing agents (Kono, 2015). Besides prohibiting the sunlight from reaching the aquatic plants and prevent photosynthesis process to take place, dyes

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exist in environment is also known to be very much associated with carcinogenic and toxic properties (Islam et al., 2017c). The existence of dyes even in slight amount is adverse because it can change the colour of water bodies. Dyes can easily be distinguished into two main groups of ionic dyes and non-ionic dyes. Under ionic dyes, further classification can be made in terms of cationic dyes and anionic dyes.

Cationic dyes which consist of basic dye poses the property to dissolve in water to produce positive ions whereas anionic dyes which consist of acid, direct and reactive dyes pose the property to dissolve in water to produce negative ions. This characteristics increase their polar solubility in water thus making them more challenging to remove as compared to non-ionic dyes. This is the reason why most researchers are focussing on removing ionic dyes (Sangon et al., 2018, Silva et al., 2018a, Lam et al., 2017).

Methylene blue (MB) dye belongs to the basic group which is used to dye silk, wool, paper, polyacrylonitrile, modified nylon and polyesters whereas metanil yellow (MY) dye belongs in the group of acid dye and is useful to dye nylon, wool, silk, modificed acrylics, leather, paper and ink-jet printing (Ahmad et al., 2015). As basic dye, MB is popular in textile industry due to its bright colour. However, upon contact with humans and animals, MB can cause injury to the eyes and temporarily breathing difficulty. It was also reported that basic dye can cause more serious health problem including tissue necrosis, quadriplegia, methemoglobinemia and the worst of all, mental confusion (Kushwaha et al., 2014).

On the other hand, metanil yellow (MY) dye is preferred in the textile industry since it has sulfonate group (R-SO3Na) in its molecule that enhances its binding properties with cellulose fibers. In terms of molecular structure, MY can be categorized as azo dye as well since it has stable azo bond (N=N) in its structure.

3

Among all dyes, azo dyes have the highest demand in textile industry which up to 60-70% of the total dyes that being consumed (Cheng et al., 2015). Upon contact with humans or living organism, acid azo dye such as MY can cause renal complications, abnormality in reproductive system and dermatological diseases (Yagub et al., 2014).

1.2 Agrowaste based activated carbon

One of the most promising dyes treatment method is adsorption process using commercial coal based activated carbon (AC) as the adsorbent. Unfortunately, high cost of raw materials, depleted sources of raw materials and non-renewable of raw materials are several factors that limit the production of AC. Therefore, researchers nowadays are making an effort to produce AC from agrowaste as an alternative to the common raw materials such as coal and petroleum coke. Some examples of agrowastes that are successfully converted into AC include date (Norouzi et al., 2018), rice straw (Sangon et al., 2018), reed (Zhou et al., 2017), corncob (Tharaneedhar et al., 2017), rattan (Islam et al., 2017a), cattail (Yu et al., 2017), karanj fruit hull (Islam et al., 2017c) and orange peel (Lam et al., 2017).

Durian seed and jackfruit seed are selected in this study to be converted into AC to treat MB and MY dyes in aqueous solution. The scientific name for durian is Duriozibethinus L. and is referred by the local residents as “king of fruits” (Ahmad et al., 2015). Durian is a seasonal tropical tree that belongs in the family and genus of Bombacaceae and Durio respectively. This fruit is typically ovoid in shape and famous due to its distinctive, strong and penetrating smell. The edible part of this fruit is contained inside the shell which is yellowish brown in colour and having sharply pointed pyramidal formidable thorns (Subhadrabandhu and Kesta, 2001).