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Granular activated carbon (GAC) and powdered activated carbon (PAC) are the two most common forms of activated carbon with varying particle size range. The goal of this study was to analyze the key factors (particle size and activation temperature) affecting the surface characteristics of GAC and PAC derived from palm kernel shell (PKS). The surface morphology suggested that the pore network in PKS-PAC is more developed than that in PKS-GAC owing to the presence of a micropore structure when prepared at lower activation temperatures. This study also demonstrated that activation performed on different PKS particle size range influenced the mesopore domain of the activated carbon produced. The PKS-GAC was found to have more mesopores than PKS-PAC, which made it more reliable for dye adsorption in water treatment. Overall, this study demonstrated that applying different particle size range of PKS during the activation process can have a significant influence on the surface characteristics, thus having a direct impact on the application of activated carbon. An accurate particle size range will ensure that the most cost-effective activated carbon is selected to achieve the desired performance objectives.

The effectiveness of chemical steeping was examined as a novel pretreatment prior to hydrolysis to influence the extractable yield of glucose and xylose from oil palm trunk (OPT). The chemical steeping parameters were 0.2% sodium metabisulphite (w/v), 0.5% lactic acid (v/v), 26 ± 2 °C, and 1 h, followed by dilute acid hydrolysis (2%, 4%, and 6% of sulphuric acid (v/v); 115 °C, 120 °C, and 130 °C; 15 min, 30 min, and 60 min). For comparison, the glucose and xylose yield extracted from untreated OPT was also examined. Thermal analysis showed that the lactic acid and sodium metabisulphite successfully degraded the lignocellulose of OPT. The total extracted glucose and xylose yield was improved, and was approximately 2.5% to 28.8% higher than the yield extracted from non-pretreated OPT fines. RSM analysis showed that the 130 °C x 50 min x 2% was predicted as the optimum parameters for the extraction of glucose and xylose through chemically treated OPT, and followed the dilute acid hydrolysis process. Analysis of variance showed that the hydrolysis parameters were significant model terms for the glucose and xylose yield. In conclusion, chemical steeping was successful as a pretreatment to increase the extractable glucose and xylose yield from OPT.

Shifting an individual’s belief toward sustainability issues will need changes in perception. A collective modification in perception will be successful when a sufficient number of people understan...

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.

An approach of green in situ synthesis single-step method was applied to produce antibacterial paper. The objective was to investigate the effect of precursor addition on the formation of zinc oxide particles using an in situ single-step method. Zinc chloride concentrations of 0.1, 0.3, 0.5, and 0.7 M were prepared and added into a solution of algae extract and bamboo pulp. The prepared pulps were tested and made into handsheets using a papermaking machine based on TAPPI T205 (2006). Morphological observation of treated papers was conducted using a field emission scanning electron microscope (FESEM). An average of 400 to 570 nm zinc oxide spherical-shaped particle was observed on the fibers of paper. The percentage of element composition of the treated paper were 15.08% to 34.08% of zinc and 17.45% to 32.59% of oxygen captured via scanning electron microscopy with energy dispersive X-ray (SEM-EDX) analysis. The crystallinity test was performed using X-ray dispersion (XRD). A higher percentage of precursors exhibited a more amorphous structure. A measurement of more than 30% increment of inhibition zone was obtained from 10.00 to 25.00 mm against S. aureus, S. choleraesuis, and E. coli. Precursors addition of more than 0.3 M would have the most potential to enhance the growth of zinc oxide via in situ preparation, hence providing better antibacterial properties of the prepared papers.

The discovery of new methods to control porosity and microarchitecture may lead to the refinement of carbon materials from lignocellulose as advanced functional materials. However, the high ash content on the surface of lignocellulosic biomass reduces the surface area and adsorption properties of the activated carbon. This study presents a novel approach, using a deashing post-treatment as the pore generator, to increase the quality of the activated carbon. The micropore capacity was improved by deashing post-treatment with distilled water, where 80% of the total pore ratio of the activated carbon was occupied with micropores. Ultrasonic treatment was able to penetrate deeper into the structure of coconut shell activated carbon, creating cavities and pores, thus increasing the surface area. Understanding the effects of these new controlling methods on pore refinement can elucidate the microporous fabrication of other activated carbons from high ash-content lignocellulosic biomass.

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.

Time and storage space are the main constraints facing by the current Malaysia composting industries which are handling lignocellulosic food industry waste such as empty fruit bunch (EFB), coffee ground (CG) and palm oil mill sludge (POMS). To develop an efficient accelerated composting method for lignocellulosic food industry waste in Malaysia, a new approach which combined two distinct technologies to achieve rapid composting; (i) co-composting with combination of different lignocellulosic materials and (ii) inoculation of the co-composting with mixture of microorganism were presented in this study. All the mixtures achieved thermophilic condition on the first week of composting, with 50% EFB + 50% CG combination recorded the highest temperature of 56 °C. The mixtures with initial C/N ratios within 25–35 showed the highest reduction in holocellulose, cellulose, hemicellulose and lignin content while compost mixture with initial C/N ratio more than 50 had a minimal reduction. The C/N ratio for 50% EFB + 25% CG + 25% POMS combination was reduced to less than 20 after 4 weeks of co-composting process while the other treatments needed longer composting duration. During thermophilic phase, higher population of bacteria (107–108 CFU/g DW) was observed, followed by fungi (105–106 CFU/g DW) and actinomycetes (105–106 CFU/g DW) populations. However, higher population of actinobacteria (104–106 CFU/g DW) compared to bacterial (104–105 CFU/g DW) and fungal (103–104 CFU/g DW) was found during latter stages. By reducing both the time and space required for composting lignocellulosic food industry waste, this accelerated co-composting method may be a viable option for food industries searching for a long-term, practical solution for solid biowaste disposal issues.

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 tenacious R. microporus.

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.

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 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 10 6 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 10 9 CFU ml −1 creates a high toxicity and repellent barrier for termites. Pseudomonas aeruginosa of 10 9 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.

White root disease caused by Rigidoporus microporus is the most devastating disease in majority of the rubber growing countries, including Malaysia. This study aimed to screen and decipher the mech...

Ash related operational problem is one of the most prominent issues in using lignocellulosic biomass as solid biofuel. This study evaluates the effect of kaolin and calcite addition as fuel additives on the ash melting characteristic and heating value of the oil palm biomass (empty fruit bunch and oil palm trunk). Both additives significantly improved the ash melting characteristic of the oil palm biomass. While the concentrations of additives act as a variable to increase the sintering temperature, it also had strong impacts on higher heating value reduction and ash content increment. Kaolin reduced the sintering degree of the ashes with the formation of inorganic elements mixtures mostly detained in the ash sediments. In compare, the presence of calcite helped to increase the ash melting temperature but at the same time induce higher concentration of fly ash in the flue gas. Overall, kaolin is more efficient than calcite to decrease the sintering degree of the ashes from molten to loose with the measure of 0.5 g/g ash while calcite require higher dose (at the dose higher than 0.7 g/g ash) when combusted at 1000 °C.

The peeling of small-diameter rubberwood logs from the current short-rotation practices undoubtedly will produce lower grade veneers compared to the veneers from conventional planting rotation. Hence, this raises the question of the properties of the produced laminated veneer lumber (LVL) from veneers peeled from small-diameter rubberwood logs using the spindleless lathe technology. Different thicknesses of rubberwood veneers was peeled from rubberwood logs with diameter less than 20 cm using a spindleless lathe. Three-layer LVLs were prepared using phenol formaldehyde (PF) adhesive and hot pressed at different temperatures. During the peeling of veneer, lathe checks as deep as 30–60% of the veneer thickness are formed. Owing to deeper lathe check on 3 mm rubberwood veneer, higher pressing temperature significantly increased the gluebond shear strength of the PF-bonded LVL. In addition, lathe check frequency was also shown to influence the bond strength. The presence of higher lathe check frequency on 2 mm veneer increased the wettability, thus facilitating optimum penetration of adhesive for stronger bonding. These findings stress the importance of measuring and considering the lathe check depth and frequency during the lamination process to get a better understanding of bonding quality in veneer-based products.

1,3-dimethyl-4,5-dihydroxyethyleneurea (DDHEU) and 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) were used as the binders in 3-mm high density fiberboard (HDF) manufacturing. The studies focus ...

Empty fruit bunches (EFB), coffee grounds (CG), and palm oil mill sludge (POMS) were composted in the laboratory for 60 days in order to study the composting process of lignocellulosic food industry wastes. In the first part of the experiment, EFB, CG, and POMS were composted alone (composting of single lignocellulosic material), and in the second part, EFB was composted with CG (1EFB:1CG ratio) and POMS (1EFB:1POMS ratio). The effects of different turning frequencies on the physical and chemical properties of composting were observed and its relation with the degradation process was highlighted. Results showed that oil and grease were first degraded, followed by recalcitrant compounds like alpha-cellulose, hemicellulose, and lignin. Cellulose and hemicellulose were degraded mainly during the 60 days of composting, and the progressive reduction of the cellulose/lignin ratio proved that the main evolution of these wastes took place. It was observed that 3, 6, and 9 days of turning frequency did not...

Global energy sectors are facing the crucial challenge of sustainability and diversification of energy resources. Seeking renewable resources with a sustainable supply is therefore a matter of the utmost concern. In this respect, bamboo, a renewable lignocellulosic material and non-food biomass, has great potential to be utilized to produce energy. Several studies have been conducted on a wide range of bamboo species and the results have shown that bamboo could potentially be used as a suitable fuel because it shares desirable fuel characteristics present in other woody biomass. Bamboo can be used as an energy source by converting it into solid, liquid, and gaseous fuels. However, to utilize bamboo as a high promise energy crop resource for biofuels, a secure and stable supply is required. Therefore, additional information on the availability, cultivation, and harvesting operations of bamboo is vital to ensure the practicability of the idea. The objective of this review is to highlight the potential of bamboo as an alternative source of bioenergy production, particularly in a Malaysian context, with emphasis on the concepts, pretreatment, and conversion technologies.

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 (H 3 PO4), 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 H 3 PO4 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 3 PO4 at 80 °C for 2 h. The impregnation pretreatment simultaneously unclog existing pores from ash minerals while create new cracks and pores.

The effect of carbon to nitrogen (C/N) ratios towards facultative co-digestion of palm oil mill effluent (POME) and empty fruit bunches (EFB) in terms of methane production and biodegradability of the substrates was experimentally evaluated. The experiment was performed with different EFB and POME loadings which are adjusted to specific C/N ratios. Based on the methane production, gross electricity production from the co-digestion was also calculated and presented. The results showed that cumulative methane production increased from 0.17 L CH 4 (without EFB admixture) to 2.03 L CH 4 in response for the treatment with C/N ratio of 45. After the digestion process, BOD and hemicellulose shows the highest biodegradability rate in POME and EFB, respectively. The maximum estimated gross electricity production of 196 kWh was observed with C/N ratio of 45 (10 L of POME, 3.1 kg of EFB). Conclusively, co-digestion of POME with EFB generates higher methane production, and this relates with the higher degradation of organic substrates.

Mediatorless cellulose-fed microbial fuel cell (MFC) is a bioelectrochemical system that converts cellulose into energy through cellulose-hydrolyzing and electrogenic activity of bacteria. In the paper it has been presented that Enterobacter cloacae isolated from termite gut exhibited both cellulose-degrading and exoelectrogenic activities that make it a valuable strain to be used in a cellulose-fed MFC. The maximum power and current densities obtained from the cellulose-fed MFC were 185 mW/m 2 and 2.4 A/m 2 , respectively. SEM micrographs of the anode showed that E. cloacae formed an expanded fibria system bounding bacteria cells into network attached to the electrode surface.

The usage of high ash content biomass for heat and electricity generation may lead to various ash-related problems, primarily to heating value, ash and combustion characteristics. The study aims at studying the effectiveness of leaching on removing ash forming elements and increasing ash melting temperature using water and acetic acid as the extraction agent. Leaching by acetic acid solutions removed most of the ash forming elements, with ash melting characteristics under high temperature were considerably improved. If the ash removal efficiency and HHV were to be taken as consideration for the selection of leaching treatment, acetic acid leaching method will be the most preferable treatment. Using the method established in this research, the lignocellulosic biomass presented in this study can be prepared for combustion with the assurance that ash forming elements have been reduced sufficiently to safeguard against ash production, corrosion and slagging in biomass boiler.

Value added manufacturing activity in the wood sawmilling industry of Peninsular Malaysia is important for employment opportunities, particularly for low income citizens living in this rural area, to provide returns to the local economy while being environmentally sustainable. This paper is a review on the value added wood sawmill industry in Peninsular Malaysia, using the value of major import and exports of major timbers products and forested area in Peninsular Malaysia over the period 2003 to 2012. The productivity performance measures that are based on the concept of value added are emphasized in this paper. The value added in wood sawmill industry was found to increase from year 2003 to 2012. Consequently, Malaysia is moving on the right path to achieve the goal of National Timber Policy 2020, transforming the timber industry into high value addition industry. However, further analysis using the value added productivity measure found that the value addition rely on international timber price rather than skilled workers.

Termites thrive in great abundance in terrestrial ecosystems and the symbiotic gut microbiota play important roles in digestion of lignocelluloses and nitrogen metabolism. Termites are excellent models of biocatalysts as they inhabit dense microbes in their guts that produce digestive enzymes to decompose lignocelluloses and convert it to end products such as sugars, hydrogen, and acetate. Different of digestive system between lower and higher termites which lower termites dependent on their dual decomposing system, consisting of termite's own cellulases and gut's protists. Higher termites decompose cellulose using their own enzymes, because of the absence of symbiotic protists. Termite gut prokaryotes efficiently support lignocelluloses degradation. In this review, a brief overview of recent experimental works, development and commercialization is discussed. Significant progress has been made to isolate cellulolytic strains from termites and optimise the digestion efficiency of cellulose. Future perspective should emphasize the isolation of cellulolytic strains from termites, genetically modifying or immobilization of the microbes which produce the desired enzyme and thus benefits on the microbiology and biotechnology.

Malaysia is the biggest producer of palm oil in the world. The production generates large amounts of waste trunks which should be considered a valuable bio-feedstock rather than waste. An approach for valorization of waste oil palm biomass – especially that of low density hardly applicable in industry – through furfurylation was investigated. Furfuryl alcohol treatment resulted in great improvement in the properties of the material: 200% density gain, water absorption and thickness swelling reduced by 50% and 74%, respectively, hardness increased by 400%, as well as 3.5-fold and 7.4-fold increase, respectively, in bending strength and modulus of elasticity was observed. Alternations in physical and mechanical properties of oil palm trunk combined with aesthetic changes due to material darkening may be considered an effective approach for conversion of waste biomass to novel materials of enhanced technical value.

In Malaysia, large amounts of organic materials, which lead to disposal problems, are generated from agricultural residues especially from palm oil industries. Increasing landfill costs and regulations, which limit many types of waste accepted at landfills, have increased the interest in composting as a component of waste management. The objectives of this study were to characterize compost feedstock properties of common organic waste materials available in Malaysia. Thus, a ratio modelling of matching ingredients for empty fruit bunches (EFBs) co-composting using different organic materials in Malaysia was done. Organic waste materials with a C/N ratio of30 can be applied as a nitrogen source in EFB co-composting. The outcome of this study suggested that the percentage of EFB ranged between 50% and 60%, which is considered as the ideal mixing ratio in EFB co-composting. Conclusively, EFB can be utilized in composting if appropriate feedstock in term of physical and chemical characteristics is coordinated in the co-composting process.

Huge amount of oil palm trunks were made available during replanting activities to replace the unproductive oil palm trees. In this study, 30-years old oil palm trunks were used. The oil palm trunk (OPT) were treated respectively with different solid content (10%, 20% and 30%) of aqueous urea formaldehyde (UF) under three level of impregnation pressure 8 MPa, 10 MPa and 12 MPa for 15 min, 30 min and 60 min. Three-layered board was produced by laminating impregnated OPT with 0.5 mm thick veneer at 180 g/m 2 glue spread rate and hot pressed using 6 MPa pressing pressure at temperature of 110 °C for 4 min. It was observed that increase of impregnation pressure and time did not improve the physical and mechanical properties of the three-layered board. The results from soaking test showed that the three-layered board produced from OPT impregnated with higher resin solid content and shorter impregnation time eventually reduced the degree of water absorption and resulted in dimensional changes of its thickness and width. Furthermore, the impregnation treatments on the core layer increased the modulus of rupture (MOR) and shear strength of the board but a reduction in modulus of elasticity (MOE). The optimum UF impregnation treatment which produced the highest mechanical and physical properties was the treatment with 30% UF solid content, 10 MPa impregnation pressure and 15 min impregnation time.

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 N 2 ) 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 m 2 g −1 , CS: 479.17 m 2 g −1 ), pore size (PKS: 0.63 nm, CS: 0.62 nm) and pore volume (PKS: 0.13 cm 3 g −1 , CS: 0.15 cm 3 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.

Without appropriate treatment, lignocellulosic biomass is not suitable to be fed into existing combustion systems because of its high moisture content, low bulk energy density and difficulties in transport, handling and storage. The aim of this study was to investigate the effects of torrefaction treatment on the weight loss and energy properties of fast growing species in Malaysia (Acacia spp., and Macaranga spp.) as well as oil palm biomass (oil palm trunk and empty fruit bunch). The lignocellulosic biomass was torrefied at three different temperatures 200, 250 and 300 °C for 15, 30 and 45 min. Response surface methodology was used for optimization of torrefaction conditions, so that biofuel of high energy density, maximized energy properties and minimum weight loss could be manufactured. The analyses showed that increase in heating values was affected by treatment severity (cumulated effect of temperature and time). Our results clearly demonstrated an increased degradation of the material due to the combined effects of temperature and treatment time. While the reaction time had less impact on the energy density of torrefied biomass, the effect of reaction temperature was considerably stronger under the torrefaction conditions used in this study. It was demonstrated that each biomass type had its own unique set of operating conditions to achieve the same product quality. The optimized torrefaction conditions were verified empirically and applicability of the model was confirmed. The torrefied biomass occurred more suitable than raw biomass in terms of calorific value, physical and chemical properties. The results of this study could be used as a guide for the production of high energy density solid biofuel from lignocellulosic biomass available in Malaysia.