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An integrated and feasible approach was proposed using the underutilized grass fibre (stem) derived from Napier grass and sugarcane for paper production in this study. To enhance paper strength, pre-hydrolysis and beating techniques have been used to improve the chemical pulps and mechanical pulping process, respectively. Napier grass and sugarcane are promising non-wood sources for pulp production, owing to their high cellulose and low lignin and extractive content. With the additional mild alkaline pre-treatment to the mechanical pulping process, t he lig nin content was greatly reduced. The results reveal that the mechanical pulping with alkaline pre- treatment may indeed potentially replace the most prevalent pulping process (chemical pulping). As evidenced by the paper strength properties, mechanical pulping is far more suitable for grass-type biomass, particularly Napier grass, which had a folding endurance capability five times greater than chemical pulping. Furthermore, the remaining high hemicellulose content from mechanical pulping contributed to a high pulp yield, while also facilitating the fibrillation on the sugarcane’s laboratory paper handsheet. The findings also demonstrated that the additional beating process from chemical pulping causes the fibres to be drawn toward each other, resulting in a more robust fibre network that contributes to good paper strength. Consequently, this work sheds new light on the development of advanced paper derived from grass fibre.

The development of low-environmental-impact technologies for the elimination of biological damage is one of the vital goals of the wood protection industry. The possibility of utilizing pyroligneous acid as a wood preservative can be a great solution to extend the application of the currently fast-growing timber species, which has lower natural durability against biological damage. In this study, the effectiveness of pyroligneous acid as a wood preservative was evaluated by impregnating rubberwood with pyroligneous acid using vacuum-pressure treatment, and the treated woods were exposed to mould fungi, wood-decay fungi and termite attacks under laboratory conditions. Pyroligneous acids produced from rubberwood (RWPA) and oil palm trunk (OPTPA) at different pyrolysis temperatures were evaluated. To fully understand the effectiveness of pyroligneous acids as wood preservatives, different concentrations of pyroligneous acids were impregnated into rubberwood. Concentrations of 50% RWPA and 30% OPTPA were sufficient against mould and decay fungi on rubberwood. Rubberwood impregnated with pyroligneous acid acted as a slow-acting toxic bait to cause a high termite mortality rate due to toxic feeding and does not serve as a good repellent to prevent termites from feeding on the wood. In general, OPTPA has better biological durability compared to RWPA.

One of the lignocellulosic wastes that has obtained much interest in Malaysia is oil palm empty fruit bunch (EFB). EFB is sustainable and renewable as it is generated from the crude palm oil process as a by-product. As the whole fruit bunch undergoes the steaming process in the palm oil mill, EFB is normally in a wet condition with very high moisture content. If it is not processed immediately, EFB is prone to degradation, which affects the quality of the fiber. Basically, EFB consists of cellulose, hemicellulose, and lignin. EFB fibers are partially separated by shredding the bunches. Some of the palm oil mills double shred the bunch and send it out to their plantations as mulching material. However, many of the mills just pile it at the plantation, letting it degrade slowly to create organic stockpile for the soil. Despite utilizing EFB for this low-end usage, EFB fiber has the potential to produce higher end products and has been recognized as an important lignocellulosic biomass. Due to its abundant availability in Malaysia, it is potentially considered as the main candidate as a substitute for wood and to assist in dealing with wood shortage problems.

The success of microbial termiticides in controlling termites depends on the ability of microbes to grow in different media and the functionality of the microbes as a resistant barrier or toxic bait. This study was conducted to understand the mortality rate and behaviour changes of the subterranean termite Coptotermes curvignathus Holmgren introduced with different concentrations of Serratia marcescens strain LGMS 1 and Pseudomonas aeruginosa strain LGMS 3 using wood and soil as bacterial transfer medium. In general, higher concentration of bacteria in soil caused a reduction in tunnelling activity and wood consumption and an increase in mortality. However, application on wood revealed a different outcome. Wood treated with S. marcescens of 106 CFU ml-1 concentration proved to be more efficient as bait than higher concentration applications as it caused a high mortality rate while still highly palatable for termites. Wood or soil treated with S. marcescens concentration higher than 109 CFU ml-1 creates a high toxicity and repellent barrier for termites. Pseudomonas aeruginosa of 109 CFU ml-1 concentrations applied on wood served as a slow-acting toxic bait. However, the ability for S. marcescens and P. aeruginosa to survive on wood is low, which made the bait unable to retain a useful level of toxicity for a long period of time and frequent reapplication is needed.

Non-renewable nature of commercial coal-based activated carbon has pushed researchers to look for sustainable alternatives which are inexpensive and abundantly available such as palm kernel shell (PKS) and coconut shell (CS). In this study, preparation of the lignocellulosic biomass using acid (HPO4), alkali (NaOH) and water pretreatment have been investigated. Pretreatment temperature and time were determined as the significant factors on the chemical–structural characteristics of CS and PKS. In addition, BET, SEM, FTIR, TGA were used to elucidate the development of PKS and CS and its capacity towards the adsorption of methylene blue and iodine. By varying the pretreatment conditions and process, it offers the possibility of modifying and controlling the porous texture of the biomass to prepare it as potential precursor for further physical thermal process during activated carbon production. The pretreated biomass results showed that the adsorption of methylene blue (14.35–16.92​ mg/g) and iodine value (20.14–23.86 mg/g) were significantly higher than non-treated biomass (methylene blue adsorption: 1.71–1.79 mg/g, iodine adsorption: 0.77–1.28 mg/g). Moreover, the results also revealed that pretreatment temperature and time have significantly affected the adsorbent properties of biomass. The pretreatment of biomass with HPO4 created a better development of porous structure. The highest surface area for CS (89.09 m2/g) and PKS (70.01 m2/g) were attained by using H PO4 at 80 °C for 2 h. The impregnation pretreatment simultaneously unclog existing pores from ash minerals while create new cracks and pores.

Unproductive young rubber trees (15 years old) with smaller diameters (15 to 18 cm) compared to conventional rubber logs, harvested at the age of 25 years old, were selected for the production of laminated panels. Spindleless rotary veneer peeling was applied to logs from short-rotation rubber forest plantations to produce veneers for structural purposes. This raises questions about the utilization of these small-diameter logs with respect to its effect on the quality of veneer and laminated panels produced. This study examines the effect of the glue spread rates on the physical and mechanical properties of rubberwood laminated veneer lumber (LVL). Analysis of variance shows that the application of a 280 g/m2 glue spread rate significantly improved the density, water absorption and dimensional stability of rubberwood LVL. The mechanical properties of rubberwood LVL produced with a 200 g/m2 glue spread rate met the minimum requirement for the 2.1E-3100F stress class; 91.05 MPa for the modulus of rupture in the flatwise direction and 50.23 MPa for compressive strength parallel to the longitudinal axis. The modulus of elasticity in the flatwise direction of 11,189.55 MPa reached the minimum requirement for the 1.5E-2250F stress class.

The aim of this study was to select the optimal conditions for the carbonization process followed by surface modification treatment with sodium hydroxide (NaOH) to obtain a highly microporous activated carbon structure derived from palm kernel shells (PKS) and coconut shells (CS). The effects of the carbonization temperature and NaOH concentration on the physiochemical properties, adsorption capability, specific surface area, surface morphology, and surface chemistry of PKS and CS were evaluated in this study. The results show that surface-modified activated carbons presented higher surface area values (CS: 356.87 m2 g−1, PKS: 427.64 m2 g−1), smaller pore size (CS: 2.24 nm, PKS: 1.99 nm), and larger pore volume (CS: 0.34 cm3 g−1, PKS: 0.30 cm3 g−1) than the untreated activated carbon, demonstrating that the NaOH surface modification was efficient enough to improve the surface characteristics of the activated carbon. Moreover, surface modification via 25% NaOH greatly increases the active functional group of activated carbon, thereby directly increasing the adsorption capability of activated carbon (CS: 527.44 mg g−1, PKS: 627.03 mg g−1). By applying the NaOH post-treatment as the ultimate surface modification technique to the activated carbon derived from PKS and CS, a highly microporous structure was produced.

A novel class of carbon nanotube (CNT)-based nanomaterials has been surging since 1991 due to their noticeable mechanical and electrical properties, as well as their good electron transport properties. This is evidence that the development of CNT-reinforced polymer composites could contribute in expanding many areas of use, from energy-related devices to structural components. As a promising material with a wide range of applications, their poor solubility in aqueous and organic solvents has hindered the utilizations of CNTs. The current state of research in CNTs—both single-wall carbon nanotubes (SWCNT) and multiwalled carbon nanotube (MWCNT)-reinforced polymer composites—was reviewed in the context of the presently employed covalent and non-covalent functionalization. As such, this overview intends to provide a critical assessment of a surging class of composite materials and unveil the successful development associated with CNT-incorporated polymer composites. The mechanisms related to the mechanical, thermal, and electrical performance of CNT-reinforced polymer composites is also discussed. It is vital to understand how the addition of CNTs in a polymer composite alters the microstructure at the micro- and nano-scale, as well as how these modifications influence overall structural behavior, not only in its as fabricated form but also its functionalization techniques. The technological superiority gained with CNT addition to polymer composites may be advantageous, but scientific values are here to be critically explored for reliable, sustainable, and structural reliability in different industrial needs.

The efficacy of additional water-soluble additives was studied relative to the physical and mechanical properties of particleboards produced from oil palm empty fruit bunch (OPEFB). Polyethylene glycol, acrylamide, and acrylic resin were selected as water-soluble additives for use in the OPEFB particleboard production process. The effects of the three additives at two different concentrations (2% and 4% of dry OPEFB mass) on the particleboard properties were evaluated. Addition of water-soluble additives increased the performance of the OPEFB particleboard. The additive concentration has a significant effect on the properties of the particleboard. With the increase of additive concentration, the internal bonding and modulus of rupture value increased while the thickness swelling and water absorption decreased. Particleboards with an additional 4% of acrylamide or polyethylene glycol achieved the highest modulus of rupture (22 MPa), highest internal bonding strength (1 N/mm2), and lowest thickness swelling (9%). All the particleboards produced with 4% of water-soluble additive achieved the standard requirements of JIS A 5908:2003 for physical and mechanical properties.

Latex production from Hevea brasiliensis rubber tree is the second most important commodity in Malaysia, but this industry is threatened by the white root rot disease (WRD) caused by Rigidoporus microporus that leads to considerable latex yield loss and tree death. This study aimed to characterize and compare the virulence of five R. microporus isolates obtained from infected rubber trees located at different states in Malaysia. These isolates were subjected to morphological and molecular characterization for species confirmation and pathogenicity test for the determination of virulence level. BLAST search showed that the ITS sequences of all the pathogen isolates were 99% identical to R. microporus isolate SEG (accession number: MG199553) from Malaysia. The pathogenicity test of R. microporus isolates conducted in a nursery with 24 seedlings per isolate showed that isolate RL21 from Sarawak has developed the most severe above- and below-ground symptoms of WRD on the rubber clone RRIM600 as host. Six months after being infected with R. microporus, RL21 was evaluated with the highest average of disease severity index of 80.52% for above- and below-ground symptoms, followed by RL22 (68.65%), RL20 (66.04%), RL26 (54.38%), and RL25 (43.13%). The in vitro growth condition tests showed that isolate RL21 of R. microporus has optimum growth at 25–30 °C, with the preference of weakly acidic to neutral environments (pH 6–7). This study revealed that different virulence levels are possessed among different R. microporus isolates even though they were isolated from the same host species under the same climate region. Taken together, field evaluation through visual observation and laboratory assays have led to screening of the most virulent isolate. Determination of the most virulent isolate in the present study is vital and shall be taken into consideration for the selection of suitable pathogen isolate in the development of more effective control measures in combating tenaciou

The invention of spindleless lathe technology has enabled veneers to be produced from small logs, such as logs from short rotation Hevea plantations, with low recovery loss. However, for structural laminated products, such as laminated veneer lumber (LVL), manufacturers are highly selective regarding the veneers for their conventional production. During the peeling process of small logs (< 18 cm), deeper and higher frequency of lathe checks were induced on veneer surface compared to the common log size used (> 30 cm). In this study, spindleless rotary-peeled veneers made from small rubber logs were processed into LVL using different lamination pressures: 7, 8, 9, and 10 kgf/cm2. The effects of lamination pressures on the physical and mechanical properties of the produced LVL were evaluated. Based on the findings, the specific gravity increased from 0.73 to 0.83 with increased lamination pressure. In terms of mechanical properties, all the values increased with lamination pressure, but with a sudden drop with 10 kgf/cm2. Understanding the effect of lamination pressure on the physical and mechanical properties can shed light on optimizing the usage of spindleless rotary-peeled veneers from small logs for the production LVL and other lamination products.

The production of bioadsorbent from palm kernel shell (PKS) and coconut shell (CS) pretreated with 30% phosphoric acid (H3PO4) was optimized using the response surface methodology (RSM). Iodine adsorption for both bioadsorbents was optimized by central composite design. Two parameters including the H3PO4 pretreatment temperature and carbonization temperature were determined as significant factors to improve the iodine adsorption of the bioadsorbent. Statistical analysis results divulge that both factors had significant effect on the iodine adsorption for the bioadsorbent. From the RSM analysis, it was suggested that using 80 and 79°C as H3PO4 pretreatment temperature and 714 and 715°C as carbonization temperature would enhance the iodine adsorption of the CS and PKS bioadsobent, respectively. These results indicated that H3PO4 is a good pretreatment for preparing PKS and CS prior to carbonization process to produce bioadsorbent with well developed microporous and mesoporous volume. The effort to produce alternative high grade and inexpensive adsorbent derived from lignocellulosic biomass, particularly in the nut shell form was implied in this research.

The methane productivity and biodegradability of facultative single- and co-digestion samples with palm oil mill wastes was evaluated on the effect of bacterial bio-augmentation. The single- and co-digestion substrates were bio-augmented with Bacillus subtillis and a methanogenic mixed culture of anaerobic microorganisms at different loading percentage. The highest methane production was recorded at 0.95 LCH4 from co-digestion sample augmented with 10% (v/v) B. subtilis while the highest methane yield of 0.7 mLCH4/g volatile solid, attained by single-digestion of palm oil mill effluent with addition of mixed methanogens at 5% (v/v). Cumulative methane production for single-digestion increased from 0.17 LCH4 to 0.32 LCH4 in response to the bio-augmentation treatment with 5% mixed methanogens. Conversely, additional mixed methanogens to co-digestion substrate resulted 75% reduction in methane production compared to non-augmented co-digestion substrate. Addition of B. subtilis into co-digestion was more beneficial than mixed methanogens due to the cellulolytic degradation ability of B. subtilis to digest the lignocellulolytic substances in empty fruit bunch.

In the present study, agricultural biomass—palm kernel shell (PKS) and coconut shell (CS)—was used to produce high porosity bioadsorbent using two-stage continuous physical activation method with different gas carrier (air and N2) in each stage. The activation temperature was set constant at 600, 700, 800 or 900°C for both activation stages with the heating rate of 3°C min−1. Two parameters, the gas carrier and activation temperature, were determined as the significant factors on the adsorption properties of bioadsorbent. BET, SEM, FTIR, TGA, CHNS/O and ash content were used to elucidate the developed bioadsorbent prepared from PKS and CS and its capacity towards the adsorption of methylene blue and iodine. The novel process of two-stage continuous physical activation method was able to expose mesopores and micropores that were previously covered/clogged in nature, and simultaneously create new pores. The synthesized bioadsorbents showed that the surface area (PKS: 456.47 m2 g−1, CS: 479.17 m2 g−1), pore size (PKS: 0.63 nm, CS: 0.62 nm) and pore volume (PKS: 0.13 cm3 g−1, CS: 0.15 cm3 g−1) were significantly higher than that of non-treated bioadsorbent. The surface morphology of the raw materials and synthesized bioadsorbent were accessed by SEM. Furthermore, the novel process meets the recent industrial adsorbent requirements such as low activation temperature, high fixed carbon content, high yield, high adsorption properties and high surface area, which are the key factors for large-scale production of bioadsorbent and its usage.

Objective: Lignocellulosic biomass derived carbon black was thermally produced from Coconut Shell (CS) and Palm Kernel Shell (PKS). The effects of carbonization conditions on the characteristics of the produced lignocellulosic derived carbon black were studied. Methodology: Carbonization was carried out between 400 and 700EC for reaction ranging between 30 and 90 min. Practically, the carbonization temperature has a more prominent impact than the carbonization reaction time used in this experiment. Results: The result showed that high temperature carbonized carbon black had higher iodine adsorption as compared to carbon black that derived from low temperature. Prolong the reaction time resulting in structural deformation, hence less surface area for adsorption. In addition, the characteristics of carbon black from CS was fairly better than PKS carbon black in terms of iodine adsorption, surface area and fixed carbon content. The carbon black derived from PKS had lower iodine adsorption due to the poor development of porosity that contained higher ash and volatile matters. Conclusion: These study serves as fundamental tool to establish ideal production routes for carbon black manufactured from lignocellulosic biomass especially in the form of nut or seed shell.