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Laboratory and pilot scale pretreatment processes were assessed for empty fruit bunch (EFB) at different morphologies using anhydrous ammonia pretreatment (AAP). The AAP was used to deconstruct the complex structure of EFB through physical and chemical reaction to promote efficient conversion of the carbohydrates to monomeric sugars. Different morphologies of EFB samples used were unpressed EFB (UE), pressed EFB (PE), pressed and shredded EFB (PES), and lastly pressed, shredded and ground EFB (PESG). The APP process was optimized using a 1.0 L laboratory scale reactor and further scaled up to a 22 L pressure vessel (AAPB). AAP-PESG contained 76.2%, and AAP-PES contained 75.5% of structural carbohydrates, showing no significant difference. AAP-UE showed the lowest glucan conversion of 28%. The optimal laboratory conditions adopted were 135 °C, 30 min, moist to dry EFB loading of 2:1, and ammonia to dry EFB loading of 1:1. Glucan conversion of AAP-PES were 87%, 80%, and 62% at 1%, 3%, and 6% glucan loadings, respectively. The AAP-PES detected acetamide concentration at 7.3 mg/g, while AAPB-PES was only at 4.4 mg/g. Chemical composition, Fourier transform infrared spectroscopy, Brunauer Emmett Teller surface area, and scanning electron microscopy supported the assessment of AAP and AAPB processes.

Graphene nanoplatelets (GNP) were incorporated into thermoplastic starch (TPS) films, and effects on water absorption and mechanical properties were investigated. GNP inclusion formed a barrier that significantly reduced water absorption, resulting in denser TPS/GNP films. Fourier-transform infrared spectroscopy (FTIR) revealed changes in chemical interactions, and FESEM analysis showed improved GNP dispersion at this concentration. Water contact angle results indicated increased hydrophobicity with higher GNP content. Positive influences on mechanical properties, such as tensile strength and Young's modulus, were observed at 12 wt% GNP, but excessive GNP content caused agglomeration and reduced ductility. The study results highlight the potential of GNP-reinforced TPS films for improved water resistance and mechanical properties, emphasizing the need for careful optimization in future research.

Background Hermetia illucens (HI), commonly known as the black soldier fly, has been recognized for its prowess in resource utilization and environmental protection because of its ability to transform organic waste into animal feed for livestock, poultry, and aquaculture. However, the potential of the black soldier fly’s high protein content for more than cheap feedstock is still largely unexplored. Methods This study innovatively explores the potential of H. illucens larvae (HIL) protein as a peptone substitute for microbial culture media. Four commercial proteases (alkaline protease, trypsin, trypsase, and papain) were explored to hydrolyze the defatted HIL, and the experimental conditions were optimized via response surface methodology experimental design. The hydrolysate of the defatted HIL was subsequently vacuum freeze-dried and deployed as a growth medium for three bacterial strains (Staphylococcus aureus, Bacillus subtilis, and Escherichia coli) to determine the growth kinetics between the HIL peptone and commercial peptone. Results The optimal conditions were 1.70% w/w complex enzyme (alkaline protease: trypsin at 1:1 ratio) at pH 7.0 and 54 °C for a duration of 4 h. Under these conditions, the hydrolysis of defatted HIL yielded 19.25% ±0.49%. A growth kinetic analysis showed no significant difference in growth parameters (μmax, Xmax, and λ) between the HIL peptone and commercial peptone, demonstrating that the HIL hydrolysate could serve as an effective, low-cost alternative to commercial peptone. This study introduces an innovative approach to HIL protein resource utilization, broadening its application beyond its current use in animal feed.

Visual impairment and blindness constitute a prevalent global health concern, significantly impacting individuals with visual impairments and those in their immediate vicinity, thereby exerting a substantial societal disability. Sighted individuals do not encounter the same range of difficulties in their daily routines and learning as those faced by individuals with visual impairments. Nevertheless, despite the obstacles they encounter, individuals with visual impairments heavily rely on their tactile and auditory senses to gather information from the environment. As a result, they may necessitate assistance or utilize tools that can enhance their sensory acuity. Consequently, engaging in sensory activities enables individuals with visual impairments to enhance their finger sensitivity, thus facilitating sensory exploration. Consequently, the objective of this study was to investigate the potential of integrating sensory activity in the form of a module with game-based activities as a means of enhancing finger sensitivity. This was achieved by creating a sensory based activity module (sensory-BAM) that could be used to instruct individuals on how to improve their finger sensitivity. Sensory-BAM utilizes tactile activities and integrates various skills, including communication, leadership, teamwork, and creativity to achieve the learning outcomes a) increase finger sensitivity, b) recognize the texture of the materials used and c) increase hand’s strength. Therefore, a series of activities were organized, with each activity station offering a unique game that utilized different materials, such as sand, rice, fingerpaint, and playdough with different missions. Every prepared activity was centered around a tactile experience that is appropriate for enhancing finger sensitivity. Sensory-BAM consists of four game stations prepared for all participants including sand, paint, playdough and rice as the main item for improving finger sensory. Ergo, this engaging activity-game learning approach provides visually impaired individuals with a practical way to improve their tactile sensitivity and specially for visually impaired in learning Braille.

Microalgae have been found to have high prospects in wastewater treatment, particularly from agriculture. However, the uneconomical algal medium growth has become the major disadvantaged in algal industry. Multiple attempts includes the development of microalgae phycoremediation technology has been integrated into wastewater treatment to reduce the cost of expensive wastewater remediation. Utilising wastewater as a low-cost nutrient medium offers a synergistic effect of wastewater nutrient removal and co-production of valuable biomass simultaneously. This paper is mainly focused on potential, ability, strategy, application (i.e., palm oil wastewater), limitation and challenges of microalgae in agricultural wastewater treatment using phycoremediation. The understanding of cultivating microalgae using agriculture wastewater shall promote the utilisation of wastewater more sustainably in the future. The possible solutions in the application of microalgae for aquaculture and agriculture sector is also discussed in this review. Overall, the utilisation of wastewater in media cultivation for microalgae is restricted due to the expensive treatment and safety concern. However, this pitfall can be reduced in the future together with a further intensive scientific study, advanced technology, better management system and applying better standard protocol.

As additive manufacturing continues to evolve, there is ongoing discussion about ways to improve the layer-by-layer printing process and increase the mechanical strength of printed objects compared to those produced by traditional techniques such as injection molding. To achieve this, researchers are exploring ways of enhancing the interaction between the matrix and filler by introducing lignin in the 3D printing filament processing. In this work, research has been conducted on using biodegradable fillers of organosolv lignin, as a reinforcement for the filament layers in order to enhance interlayer adhesion by using a bench-top filament extruder. Briefly, it was found that organosolv lignin fillers have the potential to improve the properties of polylactic acid (PLA) filament for fused deposition modeling (FDM) 3D printing. By incorporating different formulations of lignin with PLA, it was found that using 3 to 5% lignin in the filament leads to an improvement in the Young’s modulus and interlayer adhesion in 3D printing. However, an increment of up to 10% also results in a decrease in the composite tensile strength due to the lack of bonding between the lignin and PLA and the limited mixing capability of the small extruder.

This study explores the potential of using nanocellulose extracted from oil palm empty fruit bunch (OPEFB) as a biomaterial ink for 3D printing. The research focuses on using nanocellulose hydrogels for the controlled uptake and release of proteins, with the specific protein solution being Bovine Serum Albumin (BSA). To provide a suitable material for the bioprinting process, the study examines the characteristics and properties of the printed hydrogels through various analyses, such as morphology, functional group, crystallinity, and compression test. Several parameters, such as initial concentration, temperature, and the presence of calcium chloride as an additional crosslinker, affect the protein uptake and release capabilities of the hydrogel. The study is important for biomedicine as it explores the behavior of protein uptake and release using nanocellulose and 3D printing and can serve as a preliminary study for using hydrogels in biological materials or living cells.

Nanocellulose, a refined form of cellulose, can be further functionalized on surface-active sites, with a catalyst as a regenerative agent. Newly developed adsorbents are expected to have the characteristics of good and rapid adsorption performance and regeneration properties with flexible structure using 3D printing technology. In this work, the adsorption performance of 3D printed functionalized nanocellulose was investigated using batch and fixed-bed column adsorption. Kinetics adsorption studies were divided into different adsorption models, with the pseudo-second order model showing a better correlation coefficient than the pseudo-first order and intraparticle diffusion models. The Langmuir and Thomas models were used to calculate the adsorption performance of batch and fixed-bed columns. Given the catalytic activity of Fenton oxidation, the fixed-bed column was regenerated up to five adsorption-desorption cycles, suggesting satisfactory performance of the column, with a slightly reduced adsorption capacity.

Plastic pollution has placed a significant emphasis on the need for synthesising bioplastics, such as polybutylene succinate (PBS), which is derived from succinic acid. Furthermore, environmental concerns and the depletion of non-renewable fossil fuels have initiated an interest in exploring the biotechnological route of succinic acid production via fermentation. Consequently, oil palm biomass might be a prospective substitute for the costlier pure carbon source, which is more sustainable and cost-effective due to its abundance and high lignocellulosic content. The current review focuses on the potential of oil palm biomass utilisation to synthesise succinic acid and its associated bioplastics. The pretreatment and hydrolysis of various oil palm biomass and studies on bioplastics generation from oil palm biomass are also discussed. This review also identified the challenges of manufacturing succinic acid from oil palm biomass and included several recommendations.

The effectiveness of biohydrogen conversion from biomass sources is governed by the selection of ideal biohydrogen-producing bacteria to achieve high and consistent production performance. The aim of this research was to isolate and identify a biohydrogen producer in local soil samples, as well as to evaluate its fermentability in biohydrogen production from oil palm empty fruit bunches (OPEFB). To this end, preliminary identification was performed using morphological, phenotype, biological, and 16s rRNA analyses. The fermentability of the isolate was further evaluated in a serum bottle and then in a 1.5 L anaerobic column bioreactor (ACBR) to investigate the potential for biohydrogen production using two OPEFB-based carbon sources: hydrolysate of ammonia fiber expansion (AFEX)-pretreated OPEFB and molasses from dilute acetic acid (DAA)-pretreated OPEFB. The isolated strain, Enterobacter sp. KBH 6958, was found to be capable of producing biohydrogen from various carbon sources via the pyruvate:ferredoxin oxidoreductase (PFOR) pathway. The cumulative conversion of AFEX OPEFB hydrolysate was 45% higher than that observed in DAA OPEFB molasses fermentation in the production of biohydrogen. The biohydrogen yield after fermenting AFEX OPEFB hydrolysate with Enterobacter sp. KBH 6958 was 1.55 mol H2/mol sugar, with a maximum productivity of 98.1 mL H2/h (4.01 mmol H2/L/h), whereas butyrate (10.6 mM), acetate (11.8 mM), and ethanol (4.56 mM) were found to be the major soluble metabolites. This study successfully demonstrated the biotechnological conversion of OPEFB into biohydrogen using a locally isolated strain, which not only solves environmental issues associated with the industry but may also offer a solution to the world’s energy insecurity.

The degree of maturity of oil palm fresh fruit bunches (FFB) at the time of harvest heavily affects oil production, which is expressed in the oil extraction rate (OER). Oil palm harvests must be harvested at their optimum maturity to maximize oil yield if a rapid, non-intrusive, and accurate method is available to determine their level of maturity. This study demonstrates the potential of implementing Raman spectroscopy for determining the maturity of oil palm fruitlets. A ripeness classification algorithm has been developed utilizing machine learning by classifying the components of organic compounds such as β-carotene, amino acid, etc. as parameters to distinguish the ripeness of fruits. In this study, 47 oil palm fruitlets spectra from three different ripeness levels—under ripe, ripe, and over ripe—were examined. To classify the oil palm fruitlets into three maturity categories, the extracted features were put to the test using 31 machine learning models. It was discovered that the Medium, Weighted KNN, and Trilayered Neural Network classifier has a maximum overall accuracy of 90.9% by using four significant features extracted from the peaks as the predictors. To conclude, the Raman spectroscopy method may offer a precise and efficient means to evaluate the maturity level of oil palm fruitlets.

The capacity of palm oil production is directly affected by the ripeness of the fresh fruit bunches (FFB) upon harvesting. Conventional harvesting standards rely on rigid harvesting scheduling as well as the number of fruitlets that have loosened from the bunch. Harvesting is usually done every 10 to 14 days, and an FFB is deemed ready to be harvested if there are around 5 to 10 empty sockets on the fruit bunch. Technology aided by imaging techniques relies heavily on the color of the fruit bunch, which is highly dependent on the surrounding light intensities. In this study, Raman spectroscopy is used for ripeness classification of oil palm fruits, based on the molecular assignments extracted from the Raman bands between 1240 cm−1 and 1360 cm−1. The Raman spectra of 52 oil palm fruit samples which contain the fingerprints of different organic compounds were collected. Signal processing was applied to perform baseline correction and to reduce background noises. Characteristic data of the organic compounds were extracted through deconvolution and curve fitting processes. Subsequently, a correlation study between organic compounds was developed and eight hidden Raman peaks including protein, beta carotene, carotene, lipid, guanine/cytosine, chlorophyll-a, and tryptophan were successfully located. Through ANOVA statistical analysis, a total of six peak intensities from proteins through Amide III (β-sheet), beta-carotene, carotene, lipid, guanine/cytosine, and carotene and one peak location from lipid were found to be significant. An automated oil palm fruit ripeness classification system deployed with artificial neural network (ANN) using the seven signification features showed an overall performance of 97.9% accuracy. An efficient and accurate ripeness classification model which uses seven significant Raman peak features from the correlation analysis between organic compounds was successfully developed.

Cellulose-based biodegradable hydrogel proves to be excellently suitable for the medical and water treatment industry based on the expressed properties such as its flexible structure and broad compatibility. Moreover, their potential to provide excellent waste management from the unutilized plant has triggered further study on the advanced biomaterial applications. To extend the use of cellulose-based hydrogel, additive manufacturing is a suitable technique for hydrogel fabrication in complex designs. Cellulose-based biomaterial ink used in 3D bioprinting can be further used for tissue engineering, drug delivery, protein study, microalgae, bacteria, and cell immobilization. This review includes a discussion on the techniques available for additive manufacturing, bio-based material, and the formation of a cellulose-based hydrogel.

Additive manufacturing (AM) has allowed enormous advancement in technology and material development; thus, it requires attention in developing functionalized printed materials. AM can assist in efficiently manufacturing complex tailored electrodes for electrochemical sensing in the food industry. Herein, we used a commercial fused deposition modeling (FDM) filament of acrylonitrile butadiene styrene (ABS) for FDM 3D printing of a self-designed electrode with minimal time and cost compared to a commercial electrode. A graphene-based ABS conductive filament (ABS-G) was used to fabricate the conductive electrode in a dual-nozzle FDM 3D printer. The electrochemically conductive 3D printed electrode was characterized using cyclic voltammetry and tested against standard 3-monochloropropane-1,2-diol (3-MCPD) with known concentrations using an amperometric detection method. Results showed a basis for promising application to detect and quantify 3-MCPD, a food contaminant known for its carcinogenic potential. The fabrication of functionalized 3D printed polymer electrodes paves way for the development of complete 3D printable electrochemical sensors. Under optimal conditions, this newly synthesized electrochemical sensor exhibited sensitivity with a linear response range from 6.61 × 10−4 to 2.30 × 10−3 µg/mL with an estimated limit of detection of 3.30 × 10−4 µg/mL against 3-MCPD.

Oil palm Empty Fruit Bunch (EFB) was pretreated using Pressurized Ammonium Hydroxide (PAH) and was employed as Lignocellulosic Biomass(LCB) substrate for the investigation on the monomeric fermentable sugar production using the enzymatic hydrolysis process. Cellulose saccharification in enzymatic hydrolysis into a high yield fermentable sugar is an important step in Biochemical Conversion Technology (BCT). In order to determine the optimum variable conditions that can produce a high yield of fermentable sugar, a statistical approach using Response Surface Methodology (RSM) was performed in this study. Three independent variables, enzyme loading (15-50 FPU/g glucan), hydrolysis temperature (45-60°C), and agitation of the hydrolysis process (100-180 rpm) were investigated at five different levels (-α,-1, 0, +1, +α) of operating conditions and the experimental conditions were randomly setup using the Design of Experiment software. The regression models indicated that R 2 for glucose and xylose concentration was 95 and 88% showing the experimental variations were well defined by the models. For the lack of fit test, with p-values > 0.05 for both concentration sugars, 0.218 for glucose and 0.055 for xylose, it proves that the model was significant to the prediction models. The optimal conditions for the enzymatic hydrolysis of the EFB were determined at 32.5 FPU/g of glucan of enzyme loading, 50°C of hydrolysis temperature, and 140 rpm of agitation speed. The validation of the model at the optimum conditions produced a maximum glucose concentration of 8.78 ± 0.01 g/L (conversion of 81.7 ± 0.02 %, and yield of 332.95 ± 0.98 g/kg dry EFB), with a corresponding xylose concentration of 4.40 ± 0.01 g/L (conversion of 57 ± 0.35% and yield of 173.72 g/kg dry EFB).

Lignocellulosic biomass is generically known to describe a plant-based biomass, typically agricultural residues that forming a complex structure of cellulose, hemicellulose and lignin. In Malaysia, there is about 168 million tons of lignocellulosic biomass been produced locally and provide an opportunity for industries to make a breakthrough in biomass utilization. Currently, several pretreatment technologies have been progressively developed, preparing it for efficient downstream utilization such as acid or enzymatic hydrolysis. Ammoniabased pretreatment has become as one of the most attainable chemical options due to its high potential in the post- pretreatment effect and future commercial utilization. The most promising feature of this pretreatment owes to the ability of ammonia to be selective and effective in removing the lignin and allowing the carbohydrates to be easily digested in bioconversion. This paper intends to provide an overview on the biomass conversion using the ammonia-based pretreatment focusing on the fundamental concept on the lignocellulosic biomass and ammonia itself, aspect of the ammonia-based pretreatment, the chemical reaction of carbohydrates, the process from the aspect of chemical and physical changes in biomass and hydrolysis performance. This review also discusses the ammonia handling in the operation and safety precautions requirement during the development of EFB pretreatment process.

Development of polyurethane foam (PUF) containing bio-based components is a complex process that requires extensive studies. This work reports on the production of rigid PUFs from polyol obtained via liquefaction of oil palm empty fruit bunch (EFB) biomass with different isocyanate (NCO) indexes. The effect of the NCO index on the physical, chemical and compressive properties of the liquefied EFB-based PUF (EFBPUF) was evaluated. The EFBPUFs showed a unique set of properties at each NCO index. Foaming properties had affected the apparent density and cellular morphology of the EFBPUFs. Increasing NCO index had increased the crosslink density and dimensional stability of the EFBPUFs via formation of isocyanurates, which had also increased their thermal stability. Combination of both foaming properties and crosslink density of the EFBPUFs had influenced their respective compressive properties. The EFBPUF produced at the NCO index of 120 showed the optimum compressive strength and released the least toxic hydrogen cyanide (HCN) gas under thermal degradation. The normalized compressive strength of the EFBPUF at the NCO index of 120 is also comparable with the strength of the PUF produced using petrochemical polyol.

The tendency to use cellulose fibrils for direct ink writing (DIW) of three-dimensional (3D) printing has been growing extensively due to their advantageous mechanical properties. However, retaining cellulose in its fibrillated forms after the printing process has always been a challenge. In this study, cellulose macrofibrils (CMFs) from oil palm empty fruit bunch (OPEFB) fibers were partially dissolved for consistent viscosity needed for DIW 3D printing. The printed CMF structure obtained from optimized printing profiles (volumetric flow rate, Qv = 9.58 mm/s; print speed, v = 20 mm/s), exhibited excellent mechanical properties (tensile strength of 66 MPa, Young’s modulus of 2.16 GPa, and elongation of 8.76%). The remarkable structural and morphological effects of the intact cellulose fibrils show a homogeneous distribution with synthesized precipitated calcium carbonate (CaCO3) nanoparticles. The shear-aligned CMF/CaCO3 printed composite exhibited a sustained therapeutic drug release profile that can reduce rapid release that has adverse effects on healthy cells. In comparison with the initial burst release of 5-fluorouracil (5-FU) by CaCO3, the controlled release of 5-fluorouracil can be varied (48 to 75%) with the composition of CMF/CaCO3 allowing efficient release over time.

Lactic acid (LA) is a potential platform chemical that can be produced from lignocellulosic biomass. The development of a cost-competitive, catalytic-based LA production system is gaining significant attention in modern biorefineries. A series of experimental study was carried out to investigate the chemocatalytic effect of the conversion of oil palm empty fruit bunch (EFB) fibers into lactic acid under hydrothermal conditions. Synthesis of chemicals from lignocellulosic biomass involves complex mechanisms because of the complex composition of the biomass. Therefore, experimental parameters, i.e., temperature, Pb(II) concentration, and reaction time were studied. It was found that production of LA is highly dependent on the experimental conditions. In this study, the highest LA yield obtained from EFB fibers was > 46% (230 °C, 2 mM Pb(II) after 4 h of reaction). However, a similar yield can be achieved either using higher Pb(II) and shorter reactions time or vice versa. The selective production of chemical compounds (glucose, 5-hydroxymethyl furfural (5-HMF), furfural, levulinic acid, and lactic acid) from EFB fibers is highly dependent on the availability of Pb(II) ions.

Process-based contaminants in food—particularly in vegetable oils—have been a topic of interest due to their potential health risk on humans. Oral consumption above the tolerable daily intake might result in health risks. Therefore, it is critical to correctly address the food contaminant issues with a proper mitigation plan, in order to reduce and subsequently remove the occurrence of the contaminant. 3-monochloropropane-1,3-diol (3-MCPD), an organic chemical compound, is one of the heat- and process-induced food contaminants, belonging to a group called chloropropanols. This review paper discusses the occurrence of the 3-MCPD food contaminant in different types of vegetable oils, possible 3-MCPD formation routes, and also methods of reduction or removal of 3-MCPD in its free and bound esterified forms in vegetable oils, mostly in palm oil due to its highest 3-MCPD content.

The materials for additive manufacturing (AM) technology have grown substantially over the last few years to fulfill industrial needs. Despite that, the use of bio-based composites for improved mechanical properties and biodegradation is still not fully explored. This limits the universal expansion of AM-fabricated products due to the incompatibility of the products made from petroleum-derived resources. The development of naturally-derived polymers for AM materials is promising with the increasing number of studies in recent years owing to their biodegradation and biocompatibility. Cellulose is the most abundant biopolymer that possesses many favorable properties to be incorporated into AM materials, which have been continuously focused on in recent years. This critical review discusses the development of AM technologies and materials, cellulose-based polymers, cellulose-based three-dimensional (3D) printing filaments, liquid deposition modeling of cellulose, and four-dimensional (4D) printing of cellulose-based materials. Cellulose-based AM material applications and the limitations with future developments are also reviewed.

Drug delivery constitutes the formulations, technologies, and systems for the transport of pharmaceutical compounds to specific areas in the body to exert safe therapeutic effects. The main criteria for selecting the correct medium for drug delivery are the quantity of the drug being carried and the amount of time required to release the drug. Hence, this research aimed to improve the aforementioned criteria by synthesizing a medium based on calcium carbonate-nanocellulose composite and evaluating its efficiency as a medium for drug delivery. Specifically, the efficiency was assessed in terms of the rates of uptake and release of 5-fluorouracil. Through the evaluation of the morphological and chemical properties of the synthesized composite, the established 3D printing profiles of nanocellulose and CaCO3 took place following the layer-by-layer films. The 3D printed double laminated CaCO3-nanocellulose managed to release the 5-fluorouracil as an effective single composition and in a time-controlled manner.

Regenerated cellulose film with better mechanical properties was successfully produced by introducing aldehyde crosslinker during the regeneration process. The cellulose source material was derived from kenaf core powder and dissolved in LiOH/urea solvent at −13 °C to form a cellulose solution. The cellulose solution was cast and coagulated in a crosslinker bath at different percentages of glutaraldehyde (GA) and glyoxal (GX) to form a regenerated cellulose film. According to Fourier transform infrared spectroscopy (FTIR) spectra, the hydroxyl group of the cellulose was reduced, reducing the percentage of swelling as the percentage of crosslinker was increased. X-ray diffraction (XRD) patterns showed that the crystallinity index of the crosslinked film was decreased. The pore size of the films decreased as the percentage of crosslinker was increased, resulting in decreased film transparency. The pore volume and percentage of swelling in water of the films also increased with decreases in the pore size as the percentage of crosslinker was increased. The tensile strengths of the GA- and GX-crosslinked films increased by 20 and 15% with the addition of 20% of each crosslinker, respectively.

Treatment of bleaching effluents from pulp and paper mills using oil palm empty fruit bunch (EFB) fibers as an adsorbent was conducted to remove color and organic pollutants. Empty fruit bunch fibers were chemically modified with polyethylenimine to enhance the adsorption capacity toward anionic species in the effluents. Effluents from the primary clarifier and aerated treatment pond were treated, and the performance of the adsorbent was investigated in terms of decolorization, total organic carbon, and oxygen demand level. Increasing adsorbent dosage and lower pH resulted in greater adsorption performance. The highest decolorization and reduction of total organic carbon of the effluents were 95.0% and 58.2%, respectively. The adsorption equilibrium can be achieved after 4 h of the adsorption process.

In this study, lignin has been extracted from oil palm empty fruit bunch (EFB) fibers via an organosolv process. The organosolv lignin obtained was defined by the presence of hydroxyl-containing molecules, such as guaiacyl and syringyl, and by the presence of phenolic molecules in lignin. Subsequently, the extracted organosolv lignin and graphene nanoplatelets (GNP) were utilized as filler and reinforcement in photo-curable polyurethane (PU), which is used in stereolithography 3D printing. The compatibility as well as the characteristic and structural changes of the composite were identified through the mechanical properties of the 3D-printed composites. Furthermore, the tensile strength of the composited lignin and graphene shows significant improvement as high as 27%. The hardness of the photo-curable PU composites measured by nanoindentation exhibited an enormous improvement for 0.6% of lignin-graphene at 92.49 MPa with 238% increment when compared with unmodified PU.

In this study, the sorption of Cu(II) ions from aqueous solution onto NaOH-treated kenaf core fibres was investigated. The kenaf core fibres were milled into different sizes and treated with NaOH before being used to investigate their efficiency in removing Cu(II) ions from aqueous solutions. Sorption studies were performed at a pH value of 5. Sorption of the Cu(II) ions increased and the sorption yield decreased with increasing initial Cu(II) ion concentration. The sorption data were correlated with the Langmuir, Freundlich and Dubinin–Radushkevich (D–R) isotherms. The values of the correlation coefficients obtained indicated that the Langmuir isotherm fitted the experimental data better than the Freundlich and D–R isotherms. Kenaf core fibres with fibre sizes in the range 150–300 μm possessed the highest sorption capacity. The calculated parameters of the isotherms suggest that the uptake of Cu(II) ions occurred at the homogeneous active sites on the surfaces of the kenaf core fibres.