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ALKALINE PEROXIDE MECHANICAL PULPING OF OIL PALM FRONDS VASCULAR

BUNDLE FIBRES

by

OWOLABI FOLAHAN ABDULWAHAB TAIWO

Thesis submitted in fulfilment of the requirements for the degree of

Doctor of Philosophy

November 2016

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ACKNOWLEDGEMENT

Prima facea, I am grateful to almighty Allah (SWT) for granting me good health and

well-being that were necessary to complete this study. I am glad for the opportunity to thank the many people who have encouraged and supported me as I worked toward completion of this dissertation.

I am grateful to my research supervisors, Dr. Arniza Ghazali, for her pragmatic supervision and also to my co-supervisors: Prof. Dr.Wan Rosli Wan Daud and Associate Prof.

Abbas Fadhl Mubarek AlKarkhi for their valuable contributions to my Ph.D research study.

I am eternally grateful for the kindness and support of Prof. Dr. Othman Sulaiman and the wife Prof. Rokiah Ashim both in private and official capacity. My sincere thanks also go to Associate Prof. Dr. Leh Cheu Peng, Dr. Mazlan Ibrahim, En. Abu Mangsor Mat Sari, (Pak Abu) for their support and encouragement, while not forgetting the beautiful pieces of advice and guide given by my mentor Dr. Rushdan Ibrahim. May almighty Allah reward you all accordingly and abundantly.

My appreciation also goes to Dr. Wan Noor Aidawati Wan Nadhari, Dr. Rohaizu Roslan, Dr. Khadijah Olateju, Dr. Abdullah Abdurhman Dr. Fahmi Awwalludin and Ustaz Ajijolakewu for their contributions in this thesis draft.

I owe my brother Surv. (Alh.) Bashir Olayinka Kadiri, Engr. (Alh.) Mohammed Hassan Bello and Mr. Salawu a debt of gratitude for their unflagging support to my family throughout my journey away from home. I thank my fellow lab mates for the stimulating discussions, for the sleepless nights we were working together before deadlines, and for all the fun we had over the years.

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TABLE OF CONTENT

ACKNOWLEDGEMENT ii

TABLE OF CONTENT iii

LIST OF TABLES xi

LIST OF FIGURES xiii

LIST OF ABBREVIATIONS xvii

LIST OF SYMBOLS xix

ABSTRAK xx

ABSTRACT xxii

CHAPTER 1 INTRODUCTION 1

1.1 General Background 1

1.2 Pulp and Paper Lignocellulose 2

1.3 Problem Statement 4

1.4 Research Objectives 5

1.5 Structure of Dissertation 6

CHAPTER 2 LITERATURE REVIEW 8

2.1 Current Overview of Global Pulp and Paper Industries 8

2.2 Pulp and Paper Production 16

2.3 Pulping Technique 16

2.4 Hybrid Form of Pulping: Chemi-Mechanical Pulping 20

2.5 New Techniques in Pulping 21

2.5.1 Bio-Pulping Technology: 22

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2.5.2 Organosolv Pulping 22

2.6 Alkaline Peroxide Mechanical Pulping (APMP) 23

2.6.1 Pre-Conditioning with Refinesr Chemical APMP (PRC-APMP) 24

2.6.2 Enzymology in APMP 26

2.7 Alkaline Peroxide Pulping (APP) 27

2.7.1 History of Alkaline Peroxide in Industrial Revolution 28

2.7.2 Chemistry of Alkaline Peroxide Pulping 29

2.7.3 System with Alkaline Peroxide Treatment of Lignocelluloses 31

2.7.4 APMP of Various Biomass 36

2.7.5 Alkaline Peroxide Treatment of Oil Palm Biomass 38

2.7.6 Production of Nanolaminates 42

2.8 Biomass 44

2.8.1 Properties of Pulp and Paper Making Fibres 45 2.8.2 Suitability of Non-Wood for Pulp and Paper 48

2.8.3 Types of Non-Wood Fibre 49

2.8.4 Agricultural Residues - Promising Alternative to Wood Fibre 50 2.8.4(a) Special Products from Agricultural Residue 52

2.8.5 Advantages of Using Agricultural Residues 52

2.8.5(a) Economic Viability 52

2.8.5(b) Environmental Challenges 53

2.8.5(c) Technological Simplicity 53

2.9 Plant Based Natural Fibres 54

2.9.1 Processing of Plant Based Natural Fibres 55

2.10 Oil Palm Biomass 57

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2.10.1 Anatomy of OPF 59

2.10.2 Extraction of Oil Palm Biomass for Paper Making 60

2.11 Chemistry of Delignification 60

2.12 Correlation Between Bonding and Strength Properties in Paper 61

2.13 Bonding of Fibres in Paper 63

2.13.1 Inter-fibre Bonding in Paper 63

2.13.2 Van der Waal´s Interaction 64

2.13.3 Hydrogen-Bonding 65

2.14 Fibre Morphological Modification 66

2.15 Experimental Design for APMP of OPF 67

CHAPTER 3 EXPERIMENTAL METHODOLOGY 70

3.1 Introduction 70

3.2 Materials and Methods 72

3.2.1 Raw Material Preparation 72

3.2.2 List of Basic Chemicals Used in the Experiment 75

3.3 Characterisation of OPF Fibres 75

3.3.1 Morphological Analysis 76

3.3.1(a) Fibre Maceration and Measurement 76

3.3.1(b) Derived Values 77

3.3.2 Chemical Composition 77

3.4 Effect of AP on Extracted OPF Fibres 78

3.4.1 Preparation of Cooking Chemicals 78

3.4.2 AP Treatment of the OPF Vascular Bundle 78

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3.4.3 Refining Process 81

3.4.4 Pulp Screening 82

3.4.4(a) Preparation of Pulp Stock 83

3.4.5 Pulp Characterisation 84

3.4.5(a) Kappa Number 84

3.4.5(b) Determination of Residual Klason Lignin 86

3.4.6 Canadian Standard Freeness 86

3.4.7 Characterisation of the Extracted Cellulose 87

3.4.7(a) X-ray Diffraction Analysis 87

3.4.7(b) Fourier Transform Infrared (FT-IR) Spectroscopy 88

3.4.7(c) Thermogravimetric Analysis (TGA) 88

3.4.7(d) Scanning Electron Micrograph (SEM) 89

3.4.8 Fibre Quality Analyser (FQA) 89

3.4.9 Paper Formation 91

3.4.10 Paper Characterisation 92

3.4.10(a) Physical Properties of Handsheet 92

3.4.10(b) Handsheet Thickness 92

3.4.10(c) Grammage 93

3.4.10(d) Apparent Density 94

3.4.10(e) Optical Properties of Handsheet 94

3.4.10(f) Strength Properties of Handsheet. 94

3.4.10(g) Tensile Strength 95

3.4.10(h) Tear Resistance 96

3.4.10(i) Burst Strength 97

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3.4.10(j) Effect of AP Treatment and Reaction Duration 97

3.4.10(k) Scanning Electron Microscope (SEM) 98

3.4.11 Surface Modification of Handsheet 98

3.5 Study of Cooking Variables for APMP of OPF 99

3.5.1 Experimental Design 99

3.6 Regression Model Development 101

CHAPTER 4 DIMENSIONAL CHARACTERISATION OF THE OPF VASCULAR BUNDLE FIBRES

103

4.1 Characterisation of OPF Vascular Bundle Fibres 103

4.2 Dimensional Analysis 104

4.3 Chemical Composition of OPF Vascular Bundle 109

4.4 Elemental Analysis and Microscopy 113

4.5 Conclusion 115

CHAPTER 5 EVALUATION OF AP PERCENTAGE TREATMENT LEVEL AND REACTION DURATION ON THE PROPERTIES OF THE RESULTANT PULP.

116

5.1 Introduction 116

5.2 Evaluation of the Pulp from AP Treatment of the OPF 117

5.2.1 Screened Pulp Yield 117

5.2.2 Kappa Number 121

5.2.3 Canadian Standard Freeness 126

5.3 Fibre Flexibility and Conformability 128

5.3.1 Effect of AP Concentrations on Pulp Fibre Fines Distribution 130

5.3.2 Effect of Cogenerated Fibre Fines 132

5.4 Morphology of Alkaline Peroxide Extracted OPF Fibres 135

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5.4.1 Thermal Characterisation of OPF APMP Pulp 136

5.4.2 X-Ray Diffraction 139

5.4.3 Correlation between FTIR, DTG and XRD 142

5.5 Effect of Alkaline Peroxide Concentration on Paper Apparent Density 147 5.6 Effect of AP Concentrations on the Strength Properties of OPF Paper 151

5.6.1 Strength and Apparent Density Correlation of OPF Vascular Bundle

Paper 158

5.7 Effect of AP Treatment on Inter Fibre Bonding Strength 163 5.8 Effect of AP Treatment on Optical Properties of OPF Paper 165 5.9 Surface Morphological Transformation of Paper from OPF 170

5.10 OPF VB APMP Pulp Network Enhancement 175

5.10.1 Effect of Nanocoating on Paper Printability 176

5.11 Conclusion 177

CHAPTER 6 OPTIMIZATION OF AP VARIABLES 180

6.1 Introduction 180

6.2 Statistical Output 183

6.3 Regression Model Development 187

6.4 Effect of Selected Independent Variables 193

6.4.1 Screened Pulp Yield 193

6.4.2 Kappa Number 197

6.4.3 Tensile Index 199

6.4.4 Burst Index 202

6.4.5 Tear Index. 205

6.4.6 Optical Properties 207

6.5 Elucidating the Correlative Effect of the Response Variables 212

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6.6 Optimization of Alkaline Peroxide Treatment 215

6.6.1 Confirmatory Experiment 217

6.7 Conclusion 219

CHAPTER 7 CONCLUSION AND RECOMMENDATION 221

7.1 Recommendation 223

REFERENCES 225

APPENDIX 267

LIST OF PUBLICATIONS

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LIST OF TABLES

Page Table 2.1 Annual Paper Production From Malaysian Paper Mills 15 Table 2.2 Common Pulping Method for Lignocellulosic Materials 18 Table 2.3 Active Radicals and Anions from H2O2 Decomposition

in Alkaline Medium

31

Table 2.4 Progress in the Development of AP Treatment System 33 Table 2.5 Physico-Chemical Properties of Some Non-Woods

Used For Papermaking

47

Table 2.6 Categories of Plant Based Natural Fibres 55 Table 3.1 Overview of the General Experimental Work 72 Table 3.2 List of the Chemicals Used in the Study 75 Table 3.3 RSM Experimental Design Summary for AP pulping of

OPF

99

Table 4.1 Data of Dimensional Properties from OPF Vascular Bundle

104

Table 4.2 Comparison of Morphological Properties of Selected Lignocellulosic Biomass

106

Table 4.3 Chemical Compositions of OPF VB and Selected Lignocellulosices Biomass

110

Table 5.1 ANOVA for AP Level and Reaction Duration Effect on the Properties of OPF VB Fibres Network

118

Table 5.2 Standard Error for the Kappa Number 123

Table 5.3 Crystallinity Index of the OPF Vascular Bundle Fibres 140

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Table 5.4 Assignments of FTIR Absorption Bands of OPF Vascular Bundle Fibres.

145

Table 5.5 ANOVA for AP Treatment and Time Effect on Pulp Network Strength Properties

148

Table 5.6 DMRT for AP Treatment on Pulp and Paper Properties. 162 Table 5.7 ANOVA for Effects of AP Concentration and Reaction

Duration on Paper optical properties.

169

Table 5.8 Paper Printability 177

Table 6.1 Experimental Design Matrix Result from Box–Behnken RSM.

181

Table 6.2 ANOVA of the Pulp and Paper Properties of the OPF Vascular Bundles Fibres

185

Table 6.3 Correlation among the APMP Variables 213

Table 6.4 Optimal Condition for APMP of OPF VB 216

Table 6.5 Responses at the Optimum Condition of APMP for OPF VB

217

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LIST OF FIGURES

Page

Figure 1.1 Pulp and paper lignocelluloses biomass. 3

Figure 2.1 Oil palm biomass residues Source: (Dungani et al., 2013). 10 Figure 2.2 Schematic diagram of PRC-APMP process (Source:-Andritz

2004)

25

Figure 2.3 ANDRITZ MSD Impressafinesr for P-RC APMP. 26

Figure 2.4 Oil palm fibrous biomass wastes. 57

Figure 2.5 Schematic diagram of oil palm frond. 58

Figure 2.6: OPF Monochrome photography (Hashim et al., 2011). 59

Figure 2.7 Monomers of lignin. 61

Figure 2.8 Hydrogen bonding at the cellulose fibre surface with water. 65 Figure 3.1 Schematic diagram of OPF vascular bundle fibres. 70 Figure 3.2 Overview of the general experimental work. 72 Figure 3.3 Schematic transformation of leaveless OPF midrib to

vascular bundles.

73

Figure 3.4 Sample of milled OPF vascular bundle fibres particles. 74

Figure 3.5 Sieve shaker machine and sieve plates. 74

Figure 3.6 Motorized laboratory press. 79

Figure 3.7 Schematic diagram for the alkaline peroxide mixing with OPF.

80

Figure 3.8 Andritz Sprout Bauer single disc refinesr. 81

Figure 3.9 Somerville screener. 82

Figure 3.10 Glassed pulp disintegrator. 83

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Figure 3.11 Canadian Standard Freeness tester. 86

Figure 3.12 Sherwood fibre quality analyzer. 90

Figure 3.13 Semi-automated laboratory Handsheet making machine. 91

Figure 3.14 Micro gauge of Précision Micrometer. 93

Figure 3.15 BrightimeterTM Micro S-5 brightness and opacity tester. 94 Figure 3.16 Frank PTI horizontal tensile testing machine. 95

Figure 3.17 Tear testing equipment. 96

Figure 3.18 Burst testing equipment. 97

Figure 4.1 Fibre dimensions. 105

Figure 4.2 SEM-EDX analysis of the raw OPF biomass. 114 Figure 5.1 Effect of AP concentration on yield with varying OPF VB-

AP reaction duration.

119

Figure 5.2 Reject percentage. 121

Figure 5.3 Effect of AP concentration and time on Kappa number. 123 Figure 5.4 Effect of chemical charge and time on CSF. 127 Figure 5.5 Graph of CSF and bulk estimating conformability of the

fibre.

128

Figure 5.6 Schematic diagram of the various crystallinity conditions of AP fibres

130

Figure 5.7 Fibre length distribution of OPF pulp produced under optimal condition.

132

Figure 5.8 Effect of AP concentration and time on cogenerated fines. 133 Figure 5.9 Scanning Electron Micrograph of OPF vascular bundle intact

surface and transformation to fibrillated mass after APMP system.

135

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Figure 5.10 TGA curves for OPF vascular bundle fibres. 137 Figure 5.11 DTG curve of the raw and extracted OPF VB fibres. 138 Figure 5.12 X-ray diffractometry patterns of APMP pulp from OPF

vascular bundles.

141

Figure 5.13 FTIR spectra of OPF VB fibres. 143

Figure 5.14 Effect of AP treatment on paper apparent density. 149 Figure 5.15. Effect of AP treatment duration on the tensile index of OPF

fibre web.

151

Figure 5.16 Effect of AP treatment duration on the burst index of OPF fibre web.

153

Figure 5.17 Effect of AP treatment duration on the tear index of OPF fibre web.

155

Figure 5.18 Correlation between paper apparent density and tensile index.

159

Figure 5.19 Tensile energy absorption (TEA) at different AP concentrations.

163

Figure 5.20 Effects of AP concentrations on ISO brightness. 166 Figure 5.21 Effect of AP concentrations and time on paper opacity. 167 Figure 5.22 SEM images of AP paper web at different AP concentrations. 171 Figure 5.23 Effect of EFB nanolaminate coating on OPF APMP paper

strength.

175

Figure 6.1 Normal percentage probability and studentized residual plots for (A) Screened pulp yield and (B) Kappa number of alkaline peroxide pulp.

190

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Figure 6.2 Normal percentage probability and studentized residual plots for (C) tensile index and (D) burst index of alkaline peroxide pulp and paper properties.

191

Figure 6.3 Normal percentage probability and studentized residual plots for (E) tear index and (F) ISO brightness of alkaline peroxide pulp and paper properties.

192

Figure 6.4 Normal percentage probability and studentized residual plots for (G) Opacity of alkaline peroxide pulp and paper properties.

193

Figure 6.5 3-D Response surface plot for screen yield.. 195 Figure 6.6 3-D Response surface plot for Kappa number. 198 Figure 6.7 3-D Response surface plot for tensile Index. 200 Figure 6.8 3-D Response surface plot for burst Index. 203 Figure 6.9 3-D Response surface plot for tear Index. 206 Figure 6.10 3-D Response surface plot for ISO brightness. 208 Figure 6.11 3-D Response surface plot of the paper opacity. 209 Figure 6.12 Optimum conditions for APMP of OPF VB. 218 Figure 6.13. Predicted vs experimental outcome at optimality. 219

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LIST OF ABBREVIATIONS

ABS Alcohol Benzene Solubility A.D. Anno Domini (Before Christ) ANOVA Analysis of Variance

AP Alkaline Peroxide

API Alkaline Peroxide Impregnation APMP Alkaline Peroxide Mechanical Pulping APP Alkaline Peroxide Pulping

BBD Box-Behnken Design

CCD Central Composite Design CGF Cogenerated Fines Fibres

CMP Chemimechanical Pulping

CMR Chemical-Mechanical Refining

COD Chemical Oxygen Demand

CSF Canadian Standard Freeness Expressed in Terms of Millilitres CWT Cell Wall Thickness

DF Degree Of Freedom

DPTA Diethylenetriaminepenta Acetic Acid

EC European Commission

EDTA Ethylene Diamine Tetra Acetic Acid

EFB Empty Fruit Bunches

FAO Stat Food and Agricultural Organization Statistics

FL Fibre Length

FT-IR Fourier Transform Infrared H2O2 Hydrogen peroxide

HWS Hot Water Solubility

ISO International Standards Organization

KBr Potassium bromide

LD Lumen diameter

L/D Lumen Width/Fibre Diameter LSC Light Scattering Coefficient

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MPPMA Malaysian Pulp and Paper Manufacture Association

Mt Metric Ton

NaOH Sodium hydroxide

OPF Oil Palm Frond

OPF VB Oil palm fronds vascular bundles OPFB Oil Palm Fruit Bunches

OPT Oil Palm Trunk

PSI Pounds Per Square Inch

PTI Paper Testing Instrument

PRC-APMP Pre conditioning with refinesr chemical in Alkaline Peroxide Mechanical Pulping

R&D Research and Development

RR Runkel Ratio

RSM Response Surface Methodology SEM Scanning Electron Microscopy

SPSS Statistical Package For Social Sciences SS 1% Sodium hydroxide Solubility

TAPPI Technical Association of the Pulp And Paper Industry TCF Totally Chlorine Free

TEA Tensile Energy Absorption USA United States of America

VB Vascular bundles

WRV Water Retention Value

wt/wt Weight by Weight

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LIST OF SYMBOLS

oC Degree Celsius

Nm Nanometer

Mm Millimeter

µm Micrometer

ml. Millilitre

mN Millinewton

mN/m² Millinewton per square metre g/m² Gramme per square meter

L Litre

Nm/g Newton meter per gramme

kPam2/g Kilopascal square meter per gramme

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PEMULPAAN MEKANIK PEROKSIDA BERALKALI BAGI BERKAS VASKULAR PELEPAH KELAPA SAWIT

ABSTRAK

Penyelidikan ini mengkaji kualiti bagi pulpa dan kertas yang diperoleh daripada rawatan peroksida beralkali (APMP) berkas vaskular pelepah kelapa sawit (OPF) dari spesis Elaeis guineensis. Matlamat utama kajian ini adalah untuk mengkaji potensi OPF VB sebagai sumber gentian bagi penghasilan pulpa melalui teknik APMP, yang dijana melalui proses pemulpaan mekanik peroksida beralkali (APMP). Kesan penskrinan bagi berkas vaskular OPF dirawat AP dilakukan pada kepekatan AP yang berbeza. Kepekatan-kepekatan ini termasuk kepekatan AP rendah (1.0%: 1.5%; NaOH:

H2O2), sederhana (2.0%: 2.5%; NaOH: H2O2) and tinggi (4.0%: 5.0%; NaOH: H2O2).

Kesan-kesan bagi pembolehubah heterogen pemulpaan peroksida beralkali (APMP) (masa pememasakan, kepekatan natrium hidroksida dan kepekatan hidrogen peroksida) terhadap sifat-sifat pulpa dan kertas (hasil penskrinan, nombor Kappa, indeks tegangan, indeks koyakan, indeks kepecahan, kecerahan ISO dan kelegapan), telah dikaji untuk menentukan keadaan operasi yang optimum. Kaedah permukaan sambutan (RSM) menggunakan rekabentuk Box-Behnken menunjukkan gentian- gentian berkas vaskular OPF adalah sebandigan degan gentian kayu lembut dan kayu keras yang digunakan sebagai pulpa komersil dalam pembuatan kertas. Keputusan setara menunjukkan bahawa biojisim OPF VB yang melalui proses APMP menghasilkan pulpa terskrin dalam anggaran 45% - 63%. Analisis statistik menunjukkan aras bererti bagi kesan kepekatan AP terhadap semua sifat-sifat pulpa dan kertas yang dikaji pada aras keyakinan 95%, degan sokongan imej melalui

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mikroskopi imbasan elektron (SEM). Model-model regresi yang dibentuk menunjukkan keadaan operasi optimum telah dicapai melalui 2.35% NaOH, 5.00%

H2O2 dan tindakbalas antara OPF VB-AP pada 53.41 minit masa masakan. Keputusan ini adalah hasil pulpa maksimum yang diskrin (53.39%), dengan keputusan maksimum bagi sifat-sifat kertas (cth., indeks kepecahan, indeks koyakan, indeks tegangan, kecerahan ISO dan kelegapan) iaitu 6.55 kPam2/g, 6.22 mNm2/g, 9.92 Nm/g, 28.50%

and 99.71%, masing-masing beserta 80.27 nombor Kappa. Berkas vaskular OPF telah menunjukkan potensinya sebagai gentian alternatif dan sumber bahan mentah bagi penjanaan pulpa dan kertas melalui pemulpaan mekanik peroksida beralkali yang mesra alam lagi ekonomik.

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ALKALINE PEROXIDE MECHANICAL PULPING OF OIL PALM FRONDS VASCULAR BUNDLE FIBRES

ABSTRACT

This study investigates the quality of pulp and paper obtained from alkaline peroxide (AP) treatment of oil palm (Elaeis guineensis) fronds (OPF) vascular bundle or OPF VB. The principal aim of this study is to assess the potential of OPF VB as raw material and fibre source for pulp production via Alkaline Peroxide Mechanical Pulping (APMP). Screening effect of AP treated OPF VB fibres was carried out at different AP concentrations. These concentrations include AP prepared at low (1.0%:

1.5%; NaOH: H2O2), medium (2.0%: 2.5%; NaOH: H2O2) and high (4.0%: 5.0%;

NaOH : H2O2) concentrations. The effects of heterogeneous APMP variables (i.e., cooking time, sodium hydroxide concentrations and hydrogen peroxide concentrations) on the pulp and paper properties (screened pulp yield, Kappa number, tensile index, tear index, burst index, ISO brightness and opacity), were studied to determine the optimum operating conditions. Response Surface Methodology (RSM) using Box-Behnken design was used to explore the effect of selected variables on the different responses. Results indicated that the vascular bundle fibres compare favourably with the softwood and hardwood fibres used as commercial pulp for paper making. The results equally revealed that the biomass was pulpable with AP liquor and subsequent refining, resulting in screened pulp yield ranging from 45% to 63%.

Statistical analysis shows significant effect of AP concentrations on all of the pulp and paper properties at 95% confidence level, in line with the morphological changes acquired from Scanning Electron Microscopy (SEM). Regression models show that the

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optimal operating conditions of the AP were found to be 2.35 % NaOH, 5.00 % H2O2

and a 53.41 minutes cooking time. This results in maximum screened pulp yield 53.39% paper strenght value i.e., burst index, tear index, tensile index, ISO brightness and opacity were 6.55 kPam2/g, 6.22 mNm2/g, 9.92 Nm/g, 28.50 % and 99.71%, respectively with 80.27 Kappa number. The OPF VB fibres were shown to be a potential alternative fibrous raw material for pulp and paper application and this was made possible via the environmentally compatible and economic APMP process.

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CHAPTER 1 1 INTRODUCTION 1.1 General Background

Pulp and paper demand and consumption are a function of the level of development and civilization of the humanity. This implies that the more developed a nation is, the more the rate of pulp and paper consumption. The demand for pulp and paper fibre resources is largely determined by the society’s dependence on paper, paper boards and other related products for human welfare. The Directorate General of Manufacture Based Industry (DGMB), Ministry of Industry Indonesia reported that global demand for paper has grown by 2.1% annually (Adi et al., 2016).

Pätäri et al., (2016) reported that an increase in the global population would lead to the enhancement of paper needs. According to the report, the global population and economic growth predominantly focusing on developing and emerging countries is expected to increase by 1.3 billion inhabitants by 2030. Hence, industries such as pulp and paper is expected to brace up to the sustainability of the sector. Presently, despite an increasing transition to digital media usage, the global pulp and paper industry still enjoys the benefit from an increased pulp based product consumption (Ajani, 2011;

Lovins & Cohen, 2011). The Paper consumption kg/capita as of 2014 was: North America (221); EU (56); Japan (215); China (75); Korea, Taiwan, Hong Kong, Singapore & Malaysia (159); Latin America (47) and Africa (8). On average, each person consumed 57 kg of paper in 2014 (RISI, 2016). This level of per capita consumption is due to some factors, which include; the economic growth; increasing

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literacy rate; changing demographics with higher urbanization (Huang 2016). Other factors include increasing living standards, aspirations for changing lifestyles and growth of mass communication, which demands for high-quality paper and paper products (Goryakin et al. 2015).

It is projected that by 2021, the global paper production would rise to 521 million tonnes per annum. Out of this projected figures, 177 million tonnes (44%) is expected to originate from Asia while the remaining 225 million tonnes (56%) would come from elsewhere (Perkins & Rawski, 2008).

1.2 Pulp and Paper Lignocellulose

Wood has been the primary paper fibre for less than a century, with paper pulp demand being predominantly used as writing-printing paper, newsprint and industrial paper (packaging and wrapping paper, and paper board) (Holik, 2012). Global paper demand has resulted in two out of every five trees cut for pulp, , which is one of the main reasons for the destruction of forests worldwide (Middleton, 2013). Wood sourced pulp and paper has been characterized by a heavy-duty industrial process to turn wood into paper (Main, et al., 2015). Wood pulping processes release large amounts of dangerous pollutants, such as chlorine, dioxin and furans into the air and water bodies (Udohitinah & Oluwadare, 2011). As forests diminish and public opinion to save forests grows, there is increasing interest in alternative fibre crops (Laftah and Wan Abdul Rahman, 2016). Fig. 1.1 shows the common sources of lignocellulose used in pulp and paper industries (Leponiemi, 2008).

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Lignocellulose biomass contain cellulose, hemicellulose, lignin and extractives with the ratio of these components varying depending on the species of wood. While some of the fibres are virgin fibres, some are obtained from- recycle papers and non- wood fibres. The management of the forest biodiversity is a concept towards the preservation of some characteristic flora and fauna in the tropical region (Kozuka, 2013).

Figure 1.1 Pulp and paper lignocelluloses biomass.

Traditionally wood has been considered as the major raw biomass for paper making. Countries with limited forest size and limited plantation area like China are more prone to the used of non-wood as raw material for paper making (Carlsson et al., 2009; Ai & Tschirner, 2010; Mossello et al., 2010). There is significant growth of regional imbalances in the fibre supply globally due to shortage supply of virgin pulp.

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The continued rivalry in the fibre demand for pulp and paper, housing and wood for fuel has equally contributed to the reduce dependency of pulp and paper industries on virgin pulp (Carlsson et al., 2009; Ai & Tschirner, 2010; Mossello et al., 2010). Sequel to this development, agricultural residues, such as cereal straws of wheat, rice, barley and lately empty fruit bunches (introduced by EKO paper mills Malaysia) has been gaining increasing interest as fibrous source of raw materials in the pulp and paper industries (MPOB, 2012). In fact, utilisation of the agricultural residue as raw material for pulp and paper making would ameliorate the persistence waste management problems.

1.3 Problem Statement

Currently, due to the shortage of wood fibres and economic outlay the use of non-woods in pulp and paper production in several available and wood deficiency countries have been gaining increasing attention. Despite the noticeable deficiencies in the use of non-woods with respect to woods (Fazeli et al., 2016), agro wastes have been receiving increasing considerations as source of natural cellulose fibre in agro-based industries including pulp and paper industries. This development is as a result of imminent environmental instability in the area of biodiversity. Since the introduction of agro waste as alternative to wood in pulp and paper manufacture, biomass such as corn stalks (Daud et al., 2016), wheat and rice straws (Reddy and Yang, 2015), have been used for commercial pulp and paper making. Many research reported on the use of EFB for pulp and paper (Dermawan et al., 2014; Daud and Law, 2010; Ghazali et al., 2012), leaving the oil palm (Elaeis guineensis) fronds vascular bundle fibres yet fully investigated.

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A number of methods of fibre extraction have been assessed in the literature (Daud and Law, 2010; Reddy and Yang, 2015), most of, which operate at high temperatures and pressures and a few of them releasing environmental hazardous effluents. Pulping industry has been reported as the second largest polluting industry after mining (Singh et al., 2014). Air contaminants released from pulping include particulate matter, sulphur dioxide, and total reduced sulphur (TRS) compounds. To counteract the pollution issue, adoption of an eco-friendly technique with economic criteria is needed. To this date, Alkaline Peroxide Mechanical Pulping (APMP) is the best known technique that not only fit the aforementioned criteria but is also flexible in its operational size and quality of pulp as the end-product quality. Since the introduction of alkaline peroxide mechanical pulping by Cort and Bohn in the late 80s, many Kraft mills in China had been converted to an APMP system (Ghazali, 2006) and research continue to flourish around the use of various non-wood material, except the oil palm frond, OPF. This study therefore delves into the Alkaline Peroxide Mechanical Pulping of OPF VB by accomplishing the following objectives:

1.4 Research Objectives

a) To study the chemical and morphological properties of fibre residing the OPF vascular bundle.

b) To study the thermal, morphological and chemical changes in the AP- treated OPF vascular bundle by the use of TGA, SEM and FTIR of the extracted fibres respectively.

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c) To further characterize the effect of the alkaline peroxide treatment on the strength, optical and morphological properties of the handsheet from the AP- treated OPF vascular bundle fibres.

d) To develop regression model using RSM via Box Behnken design of experiment to determine the most improved and enhanced OPF pulp and paper properties.

1.5 Structure of Dissertation

The thesis consists of seven chapters that employ the use of instrumental analysis, empirical and statistical modelling approach to determine the suitability of OPF vascular bundle fibres as an alternative source of fibre for pulp and paper products.

Therefore in this dissertation:

Chapter 2: reviews the literature on the use of alkaline peroxide in pulp and paper making. The suitability of non-wood and agricultural residue for pulp and paper was enumerated. Furthermore more light on the benefit of the utilization of the statistical tool in developing and optimizing the pulping condition for pulp and paper production brought to the fore.

Chapter 3: contains all the experimental approaches undertaken in this study and gives an insight to the various tools used to analyze the obtained result.

Chapter 4: reports the result of analysis and Characterisation of the OPF vascular bundle fibres.

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Chapter 5: presents the outcome of the preliminary investigation of the alkaline peroxide treatment duration and level effects on the pulp and paper properties of the oil palm fronds vascular bundle fibres.

Meanwhile, Chapter 6: presents the result of the combined effects of three independent variables (hydrogen peroxide concentrations, sodium hydroxide concentration and cooking time) on the pulp and paper properties of the OPF vascular bundle fibres using Box Behnken model of the Response Surface Methodology (RSM) for experimental design. The chapter reports the analysis and process optimization modelling of the alkaline peroxide treatments on the pulp and paper properties.

The work is wrapped up in Chapter 7 by evaluation of the extent in , which the objectives had been achieved as well as recommendations for future research to overcome the identified challenges pertinent to APMP of OPF VB.

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CHAPTER 2 2 LITERATURE REVIEW

2.1 Current Overview of Global Pulp and Paper Industries

Pulp and paper mills are big business around the world, generating $563.6 billion in revenue during 2013 (Singh et al., 2014). The global paper and paperboard demand as at 2011 stood at 402 million tonnes per annum whereas about 7,745 mills existing globally can produce only 192 million tonnes of pulp. The paper demand has almost doubled in 20 years from 242.79 million tonnes in 1990 to 402 million tons by 2011. Paper consumption and production growth in Asia is expected to double by 2030 from 2010 levels (Alexandratos & Haen, 1995; Golley & Tyers, 2006; Oh et al., 2010).

In tropical countries like Malaysia, oil palm plantation has constituted one of the major source of gross national income (GNI). In Malaysia the oil palm export constituted $22.31 billion USD to the country’s gross national income in 2014 and it is expected to rise to $55.8 billion USD by the year 2020 (Awalludin et al. 2015). Food and Agricultural Policy Research Institute FAPRI (2010) predicts that Malaysian palm oil production will increase by 26.5 percent, to 23.4 million tonnes by 2020, slightly less than the predicted Indonesian production of 28.5 million tonnes (Ivancic and Koh, 2016). Oil palm industry in Malaysia with its 6 million hectares of plantation, produced biomass as much as 100 million tons (Abdul Khalil et al., 2010). In order to maintain steady growth of oil palm plantation, large areas of primary and secondary forest have been cut or burned down to make way for oil palm plantations in Indonesia and

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Malaysia, the two countries , which produce 80.5% of the world’s palm oil (Ivancic and Koh, 2016 ).

The conducive climatic condition of Malaysian climate has contributed absolutely to the growth of oil palm plantation, making it the most important agricultural crop in Malaysia and has contributed immensely to the national economic growth (Leibo, 2015). This has made Malaysia the second world largest producer of oil palm.

The rapid growth of the palm oil industry in South-East Asian countries like Malaysia is as a result of the palm oil being the world’s largest source of edible oil and hence constitutes its major economic crop. This has contributed to the expansion of the area of plantation and making Malaysia the second largest producer of oil palm after Indonesia (Ivancic and Koh, 2016). The types of waste biomass generated in oil palm industries in Malaysia as shown Fig 2.1 are generated from both the mill and the plantation site (Dungani et al., 2013). Fig. 2.1 shows that oil palm fronds, (OPF), and the oil palm trunks, (OPT), are generated from the plantation sites while the empty fruit bunches (EFB), palm oil mill effluent (POME), mesocap fibre (MF), and Kernel Shell (KS) are generated from the oil palm mill.

Increase in oil palm plantation translates to the huge generation of the oil palm biomass, globally over 190 million tonnes of solid and liquid residues are being generated from the palm oil industries. In Malaysia, about 100 million tonnes dry weight of these biomass wastes is projected by 2020, of , which the OPF constitutes 70% and is considered the highest (Wanrosli et al., 2007). These biomass are usually

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left on the site resulting to environmental issues while undergoing decomposition, which is aimed at fertilising the soil (Lim et al., 2000). Oil palm fronds are agricultural residues by-product biomass generated from oil palm activities and made up of the petiole, rachis and leaflets.

Figure 2.1 Oil palm biomass residues Source: (Dungani et al., 2013).

Owing to its abundance, biodegradability and problem of disposal, has contributed to the present currently increases farming costs. In addition it has lead to environmental deterioration through pollution, fires, and pests. According to Abdul Khalil and co-workers (2008), oil palm frond contains various sizes of vascular bundle fibres imbedded in thin-walled parenchymatous ground tissue. While the parenchyma cells act as a storage medium, the vascular bundle fibres act as mechanical support for the oil palm frond. This growth of the palm oil industry has caused a corresponding

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increasing in the biomass wastes derived from the pruning management practices and replanting operations (Daud and Law, 2010; Paltseva et al., 2016).

Malaysian and Indonesian based researchers have been saddled with research and development into economic viability of oil palm wastes in order to minimise if not totally eradicates the environmental issues associated with the poor management of the biomass. Biomasses such as agricultural crops and residues, forest resources and residues, and municipal wastes are the largest source of cellulose in the world (Awalludin et al. 2015). Among the merits of non-wood plants include short growth cycles, moderate irrigation and fertilization requirements and low lignin content resulting to reduced energy and chemicals use while pulping (Wang & Chen, 2013).

Agricultural by-products are annually renewable, available in abundance and of limited value at present. The use of non-wood fibres and agricultural wastes in papermaking has been proposed by some environment advocates as a way to preserve natural forests and prevention of global warming. EFB have proven to be useful raw material for the pulp and paper industries (Rushdan, 2002).

In countries where the supply of wood resources is inadequate, the rate of paper consumption continue to be on the increase despite the challenges of commercial papermaking with respect to limited wood resources. Many ecological problems occasioned by deforestation such as global warming, hurricanes, flooding, droughts are among some of the detrimental global environmental problem facing humanity (Middleton, 2013). While global campaign towards improvement in reforestation has been on the increase, the utilisation of agricultural residues have attracted the interest of environmentalist and scientist. The suitability of these agricultural biomass through

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various analytical investigation has been the first step in their utilization. For paper making, the morphology and chemical properties of fibres of the lignocelluloses for pulp and paper are of great importance to the suitability of pulping and papermaking processes, as well as for final paper products.

In India, the pulp and paper industry is divided into three sectors based on the raw materials usage (Reddy & Ray, 2011). These include:-

a) The wood based mills , which comprise of 26 large integrated paper mills using both wood and bamboo, contributes to 31% production of the mill production and this translates to 3.19 million tonnes of pulp per annum.

b) The 150 agro-based mills constitute about 25% of the total output and

c) The 538 recycle fibre mills contribute to 4.72 million tonnes, or 47% total paper product.

In Malaysia, the total capacity of the paper mills is about 50 T/day that translates to about 1,300,000 T/year. Of all these, integrated pulp and paper mill in Sipitang, Sabah (Sabah Forest) uses wood fibres (Grafton & Jago, 2013). Table 2.1 shows the total annual production capacity of the paper mills in Malaysia and the actual production per annum.

It is apparent that the production capacity per annum is short 10.52% of the total annual capacity of the of the mills. This shortfall is attributable to the lack of raw material and the maintenance culture of the machinery, , which often breakdown.

There are significant regional differences in pulp and paper consumption and production patterns. Asia is the biggest region in term of paper consumption and

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production, about twice as big as the North America (Fontagné & Fouré, 2013; Taylor et al., 2013). Perhaps the most striking fact is that Africa’s paper consumption and production are so extremely low compared to the other region. The paper making process thus far has mainly used wood materials from the cut, debarked, chipped, and pulped tree stems. The continual growth in pulp and paper production entails massive deforestation.

The pulp and paper industry is currently facing broad structural changes because of global shifts in demand and supply (Hujala, (2013), as a result of the short supply of wood materials. This challenge has led to the reductions in the number of pulp and paper mills, lower rates of capacity growth, employment downturns, and a loss of market share to foreign competitors (Brown and Wang 2015). These structural shifts portray an industry that has encountered difficulty in adapting to a more competitive environment and earning sufficient profits to generate a return on investment that covers opportunity cost. These changes have significant impacts on most national economies worldwide. Increasing competition for wood supplies for construction purposes coupled with gradually rising costs of wood have generated renewed interest in the use of nonwood plant fibres for papermaking in the highly industrialized countries (Smith, 1997). It is interesting to note that some environment advocates have proposed the use of non-wood fibres in papermaking as a way to preserve natural forests and prevention of global warming.

Both wood and non-wood resources are currently being exploited for the manufacturing of pulp, paper and paper boards. In countries where the supply of wood resources is inadequate, the rate of paper consumption has been on the increase

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despite the challenges of commercial papermaking with respect to limited wood resources.

The use of agricultural residues in pulping and papermaking is gradually gaining attention because of the problem of disposal, , which currently increases farming costs and causes environmental deterioration through pollution, fires, and pests (Bajpai, 2015). In 2003, Malaysia’s Eko Pulp & Paper Sdn Bhd (Company No. 590644- K).

(EPP) was established in joint collaboration with Forest Research Institute of Malaysia (FRIM) and Malaysian Palm Oil Board (MPOB) to undertake research and development and commercialization of pulp production using the oil palm Empty Fruit Bunches (EFB) (MPOB 2012).

Many ecological problems occasioned by deforestation such as global warming, hurricanes, flooding, droughts are among some of the detrimental global environmental problem facing humanity(Middleton, 2013). Many attempts have been made to simplify the design of the mill to achieve the reduction in the effect of the economies of scale (Karltorp & Sandén, 2012).

The global pulp production is expected to increase simultaneously with the consumption of paper, and this is especially through for fines paper with 6.5% increase in global non-woods consumption (Laftah and Wan Abdul Rahman, 2016). In China and India over 70% of raw material used by the pulp industries come from non-woody plants and agricultural residues such as reeds, bamboo, bagasse and cereal straw (Al- Mefarrej et al., 2013 ). Biomasses such as agricultural crops and residues, forest

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resources and residues, and municipal wastes are the largest source of cellulose in the world. Non-wood plants offer several advantages including short growth cycles, moderate irrigation and fertilization requirements and low lignin content resulting in a reduced energy and chemicals consumption during pulping (Wang & Chen, 2013).

Table 2.1 Annual Paper Production from Malaysian paper mills No. Company Total Capacity per Annum

(mt)

Production per Annum (mt)

1 Cita Peuchoon 30,000 24,000

2 Johmewah 35,000 8,000

3 Genting Sanyen 300,000 250,000

4 MudaPaper

(Kajang)

170,000 140,000

5 Muda Paper (S.

Prai)

130,000 140,000

6 Malaysia Newsprint

250,000 250,000

7 Nibong Paper 60,000 60,000

8 Pascorp Paper 140,000 135,000

9 Pembuatan Kertas (Perak)

3,000 3,000

10 Sabah Forest 165,000 165,000

11 Kimberly-Clark 45,000 35,000

12 See Hua Paper 12,000 10,000

13 Talping Paper 2,400 2,400

14 Then Seng Paper 15,000 11,500

15 Trio Paper 30,000 23,000

16 Union Paper 12,400 6,000

17 United Paper Board

80,000 60,000

18 Yeong Chaur S 3,600 3,600

TOTAL 1,483,400 1,327,300

(Source:- MPPMA- 2003)

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Agricultural by-products are annually renewable, available in abundance and of limited value at present.

2.2 Pulp and Paper Production

Modern pulp and paper manufacturing evolved from the ancient art first developed in China, ca. 105 A.D (Singh et al., 2014). Papers are manufactured from cellulosic fibres, generally wood (composed cellulose, lignin, hemicellulose, and extractives (e.g., resins, fats, pectins, etc.)), recycled paper, nonwood raw materials such as bagasse, cereal straw, bamboo, reeds, esparto grass, jute, flax, and sisal and agricultural residues (Main et al., 2015). In principle, papers are made by raw material preparation (wood chipping and size reduction) and handling, Pulp manufacturing (to separate and clean the fibres), Pulp Washing and Screening, Chemical recovery, Bleaching, Stock Preparation, and Papermaking (Samariha and Khakifirooz 2011). The main goal of pulping process is to remove as much lignin as possible without sacrificing fibre strength, thereby separating the fibres and removing impurities that can cause discoloration and paper instability. Hemicellulose, which is similar to cellulose in structural composition and function plays an important role in fibre-to-fibre bonding in papermaking. Other components of wood that are removed during pulping process are extractives (e.g., oleoresins and waxes).

2.3 Pulping Technique

Two basic processing steps are involved in pulp and paper production this include the conversion of fibrous raw material into pulp followed by the conversion of the pulp into paper. This processes could be achieved mechanically or chemically. The

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pulp is then bleached and further dispersed in water and reformed into a web, depending on the type and grade of paper that is needed to be produced (Bajpai 2015).

Table 2.2 gives the common pulping method for lignocelluloses materials. The first step in pulping is the cost efficient and environmental sound pulping technique even at small scale. This is what forms the interest of researchers exploring the avenue of using non-wood and agricultural residue as alternative raw material to wood. Globally, several factors have contributed to increasing the level of industry interest in the use of nonwood and agricultural residue as fibre sources. Some of these factors include :-

(a) environmental pressure to stop using trees due to deforestation

(b) projections of world fibre shortage by 2010 (Jepma, 2014), and the need to find alternative fibre sources

(c) abundance of agricultural residues (such as corn stover, sugar cane bagasse, banana pseudostem and wheat straw) that are otherwise burned off fields and

(d) opportunities of integrated mill to produce multiple products (oils, textile fibres, papermaking fibres, board fibres, plastics, food) from a simple fibre source, , which provides unique opportunities for sustainable agriculture.

Among the qualities governing good pulp and paper material in paper production is, increasing the amount of cellulose and decreasing the value of lignin, the extractive content, and the percentage ash content. All these result in increased yield, a decrease of chemical material consumption, and cooking time (Panshin & Zeeuw, 1980).

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18 Table 2.2 Common Pulping Method for Lignocellulosic Materials

Pulping method

Chemical used Properties of isolated pulp Application of pulp Refences 1 Kraft/

sulphate

Sodium hydroxide + sodium sulphide

Strong, low brightness (dark brown)

Making boxes, paper bags and wrapping paper. Can also be used for writing paper and paperboard when bleached.

(Kim et al., 2016)

2 Sulphite Sulphurous acid / sodium sulphite

High flexibility and requires little bleaching

Used in making paper and special purposes.

(Moradbak et al., 2015)

3 Soda Sodium hydroxide + anthraquinone

Have properties similar to sulphite

Ideal for all paper uses. (Wutisatwongkul et al., 2016)

4 organosolv Organic solvents and organic acids

Properties still under review

Preliminary results suggest multi-purpose uses.

(Moral et al., 2016) 5 Biopulping Involve the use of white

fungus

Increase tear index, low Kappa number and other properties are still under investigations.

Results suggest possible uses in all aspects of the paper.

(Singhal et al., 2015)

6 APMP/PRC- APMP

Hydrogen Peroxide+

Sodium hydroxide

High yielding pulp, high iso-brightness, right paper properties

Ideal for all paper uses (Cort and Bohn, 1991)

7 APP Hydrogen peroxide + Sodium Hydroxide

Same as obtained for APMP

Preliminary laboratory result suggest multi-purpose use

(Ghazali et al., 2009)

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The second step is the choice of pulping technique. Among the array of the environmentally friendly pulping is alkaline pulping, organosolv pulping, and Chemi- mechanical pulping (Sridach, 2010; Bajpai, 2013a).

There are three principal groups of pulping processes namely mechanical pulping, chemical pulping and bio-pulping. Mechanical pulpingis a pulping method that uses disc refinesr on raw wood (mainly softwood) against the abrasive surface with the aim to de-fibre the raw material without the dissolution of lignin (Harinath et al., 2013). Khakifirooz et al., (2012b) reported that this method is characterized by high yield and usually more than 95% of the dryweight of the wood. High temperature and pressure are used by some methods to increase the efficiency of the process. Although mechanical pulping generates very low polluting effects but is an energy intensive process, as the non-cellulosic wood components are not available conversely to what obtain in chemical pulping (He et al., 2013). Chemical pulping involves the dissolution of all the non-cellulosic components of the lignocelluloses biomass in cooking liquor at high temperature and pressure thereby separating the fibres. Generally chemical pulping gives better paper quality (Biermann, 1996; Bajpai, 2013a). However it is characterized with greater environmental pollution (through its pulping and bleaching process), capital intensive and operating costs are higher than those of mechanical pulping. The yield of chemical pulping is about 50% of the dryweight of raw material.

An example of the method is: sulphate or kraft, sulphite, and soda pulping.

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2.4 Hybrid Form of Pulping: Chemi-Mechanical Pulping

Hybrid pulping is another form of pulping, which involves a chemical pre- treatment of the raw material, before a mechanical treatment to liberate the fibres. The yields of these processes are situated between those for mechanical and chemical pulping (Hosseinpour et al., 2014).

Chemi-Mechanical Pulping (CMP) has gained global attention as an environmental benign pulping method (Khakifirooz et al., 2012b). It is a type of hybrid pulping process involving impregnation of raw material with small amounts of chemicals to soften the lignin, while it then employs mechanically treatment to liberate the fibres. Masrol and co-workers (2015) reported that the pulp yields of these processes are situated between those for mechanical and chemical pulping, due to the synergistic operations of the two pulping protocol in CMP. Cort and Bohn (1991) observed that heat is typically applied to improve pulping. The report further revealed that this method is characterized by good fibre properties, low chemical application, lower capital and operating costs compare to pure mechanical pulping. Chemi- mechanical pulps can be used for low- to medium-quality papers, and with additional processing they may be used for some high-end purposes. However,the most popular and widely accepted process is the invention of a new CMP technology called alkaline peroxide mechanical pulping (APMP) (Cort and Bohn, 1991). However, the dissolved lignin and the other trace elements in the biomass are treated and discharged into the environment.

Rujukan

DOKUMEN BERKAITAN

Table 3.2 Sample period of WTI and Brent during pre and post-oil shocks 18 Table 4.1 Result of the Augmented Dickey-Fuller unit Root Test for WTI 25 Table 4.2 Result of

To determine the effect of different concentration level of pre-mixed H 2 O 2 and NaOH, and the effect of treatment time on empty fruit bunch alkaline

This study was undertaken is to determine the properties of three layer particleboard from oil palm fronds and to evaluate the properties of three layer particleboard from oil

30 }I/mal EkO//(J/IIi Malaysia J4 The quantity of CPO supplied and the production of POME as a joint output are significantly affected by past quantity supplied, the

The remainder consists of huge amount of lignocellulosic materials such as oil palm fronds (OPF), oil palm trunks (OPT) and oil palm empty fruit bunch (OPEFB).. The

In examining the effect of sonication cycle time on the effectiveness of in-situ ultrasonication in increasing the rate of filtration, experiment was initially conducted

Presently, no study has been done on the characterization and film forming properties of alkaline extracted hemicelluloses, specifically hemicelluloses B (HB) from oil palm

3 rd Ed., Royal Society of Chemistry, Cambridge (UK). Sample Preparation in Analytical Methods for Pesticides and Plant Growth Regulators. VI, Academic Press, New