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Phenolic resins are thermosetting material that is commercially produced via the condensation process of phenol and formaldehyde. However, due to the usage of petro-based materials in the production of phenolic resins, several approaches have been made, and one of the approaches is by substituting the raw materials, especially phenol, with lignin. In this study, acetosolv lignin was used to produce lignin-formaldehyde (LF) and compared with phenol-formaldehyde (PF) resin. The resinification reaction was conducted at 85 °C for 4h. The functional group, curing behavior and the shear strength of the resins was analyzed using FTIR-ATR, DSC and Universal Testing Machine, respectively. The formation of PF and LF resins was confirmed by the presence of the methylene bridge functional group at 1460 cm-1. The curing curve shows the shift of LF resin to a higher temperature compared to the PF resin. Furthermore, the evaluation of bonding strength shows that LF resin possesses a low shear strength compared to PF resin. However, both resins pass to be adhesives for the manufacture of plywood panels based on standard JIS K-6852.

Three-Dimentional (3-D) printing is currently a popular printing technique that is used in many sectors. Potentially, this technology is expected to replace conventional manufacturing in the coming years. It is accelerating in gaining attention due to its design freedom where objects can be produced without imagination boundaries. The review presents a perspective on the application of 3-D printing application based on various fields. However, the ordinary 3-D printed products with a single type of raw often lack robustness leading to broken parts. Improving the mechanical property of a 3-D printed part is crucial for its applications in many fields. One of the promising solutions is to incorporate nanoparticles or fillers into the raw material. The review aims to provide information about the types of additive manufacturing. There are few types of raw materials can be used as foundation template in the printing, enhanced properties of the printed polymer nanocomposites with different types of nanoparticles as additives in the printing. The article reviews the advantages and disadvantages of different materials that are used as raw materials or base materials in 3-D printing. This can be a guideline for the readers to compare and analyse the raw materials prior to a decision on the type of material to be selected. The review prepares an overview for the researchers to choose the types of nanoparticles to be added in the printing of the products depending on the targeted application. With the added functionality of the 3-D polymer nanocomposites, it will help in widespread of the application of 3-D printing technology in various sector.

Acetosolv technique is considered as one of the best alternative way to extract technical lignin from biomass as it has high efficiency and environmentally friendly. In this study, microwave-assisted acetosolv technique were used to extract lignin from oil palm empty fruit bunch (OPEFB) in the presence of 3% sulfuric acid catalyst reacted at various temperature. The yield of the extracted acetosolv lignin were calculated using modified Technical Association of the Pulp and Paper Industry biomass composition analysis (TAPPI) method. The result showed that, as the temperature increased from 90 to 110 °C, the yield of lignin extracted also increase from 43.07 to 76.98%. The presence of guaiacyl and p-coumarate indicates the presence of active sites at C-3 and C-5 of aromatic ring for polymerization reactions. Scanning Electron Microscopy images showed that removal of lignin are intensified as the microwave-assisted acetosolv temperature increased.

In this study, a renewable phenolic component was synthesized using empty fruit bunch fibers via microwave-assisted liquefaction known as Liquefied Empty Fruit Bunch (LEFB). LEFB can be used as phenolic derivative to replace petroleum-based phenol as it contains aromatic group in lignin that can be used as starting materials to synthesis polybenzoxazine resins. A Lignin-based benzoxazine (L-PBz) has been synthesized using a solventless approach from the reaction of LEFB, furfurylamine as the amine component and paraformaldehyde via Mannich condensation reaction. Two different ratios of LEFB:furfurylamine:paraformaldehyde which are 1:1:1 and 1:1:2 were investigated. The thermal properties and polymerization behavior of the L-PBz were analyzed using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), respectively. In addition, cured-polybenzoxazine composites were also prepared by hot-pressing the uncured L-PBz at 250 °C for 4 hours, and the mechanical properties of the composites were assessed through Izod impact strength test. TGA analysis showed that, L-PBz with ratio of 1:1:1 exhibit a high char yield compared to 1:1:2 which is 47% vs 43%, respectively, after being heated until 900 °C. However, L-PBz with ratio of 1:1:2 showed good polymerization behavior compared to 1:1:1 which indicated by the curing temperature 215 °C vs 238 °C. L-PBz composites, which added with cellulose nanocrystal (CNC) fillers have better strength compared with the absence of fillers. As a conclusion, the aromatic structure of lignin in empty fruit bunch fibers has presented a promising alternative to replace petroleum-based phenol in polybenzoxazine synthesis.

In this study, soda alkali lignin from oil palm empty fruit bunch (EFB-AL) and kenaf core (KC-AL) are esterified with maleic anhydride under two different conditions, namely i) pyridine at temperature of 120°C for 3h and ii) aqueous alkaline solution at room temperature for 4h. As a result, the weight percentage gain (WPG) of the esterified EFB-AL (EFB-EL) and esterified KC-AL (KC-EL) in pyridine demonstrated a higher compared to aqueous alkaline solution. The FT-IR results of EFB-EL and KC-EL in both solvents exhibited some changes at the carbonyl and hydroxyl groups. Furthermore, the esterification process induced the carboxylic peak to appear in both alkali lignin samples. The outcome is confirmed by conducting H-NMR analysis, which demonstrated ester and carboxylic acid peaks within the spectral analysis. Finally, the TGA results showed both EFB-EL and KC-EL that are exposed to aqueous alkaline actually possessed better thermal stability and higher activation energy (Ea) compared to the esterified samples in pyridine.

Optimization of microwave-assisted liquefaction of oil palm empty fruit bunch fiber (EFB) and cellulose (EFBC) in ethylene glycol (EG) was carried out to produce polyols. The liquefaction residues and hydroxyl numbers of the resultant polyols from respective sources were studied and compared. EFB produced a minimum residue of 3.22% at the optimal parameters of 160 °C and 15 min. Meanwhile, optimum liquefaction of EFBC produced 1.03% residue at 175 °C and 40 min. The maximum hydroxyl numbers of both EFB (749.22 mg KOH/g) and EFBC (639.91 mg KOH/g) polyols were obtained at optimum conditions. FTIR analysis revealed the degradation mechanism of cellulose and lignin in EFB at different temperatures. Lignin was found to be liquefied easily at lower temperatures (130 and 145 °C). However, most of the cellulose began to be liquefied at the optimum temperature (160 °C) and severely degraded at higher temperatures (175 and 190 °C).

AbstractThe adsorption performance of cationically and anionically modified oil palm empty fruit bunch fibers toward methylene blue (MB) and phenol red (PR) was investigated using single- and multi-solute systems in a fixed-bed system. The experimental data were fit with Thomas and Clark column adsorption models to evaluate different experimental conditions (adsorbate dose, bed height, column temperature, and flow rate). The results suggest that the adsorption mechanism was that of monolayer and heterogeneous. The service time of each bed was estimated using a bed depth service time model by considering the adsorption rate. The regeneration of the adsorbent for up to five adsorption/desorption cycles was investigated, suggesting the excellent reusability of the adsorbent column. The simultaneous removal of mixed MB and PR was achieved using both fibers packed with different configurations.

The adsorption performance of cationically and anionically modified oil palm empty fruit bunch fibers toward methylene blue (MB) and phenol red (PR) was investigated using single- and multi-solute systems in a fixed-bed system. The experimental data were fit with Thomas and Clark column adsorption models to evaluate different experimental conditions (adsorbate dose, bed height, column temperature, and flow rate). The results suggest that the adsorption mechanism was that of monolayer and heterogeneous. The service time of each bed was estimated using a bed depth service time model by considering the adsorption rate. The regeneration of the adsorbent for up to five adsorption/desorption cycles was investigated, suggesting the excellent reusability of the adsorbent column. The simultaneous removal of mixed MB and PR was achieved using both fibers packed with different configurations.

Cellulosic materials derived from pineapple leaves fibers (PALF) which are being wasted after fruit harvested. There are two methods to extract cellulose from PALF. First methods were using sodium hydroxide (NaOH) 2% for alkaline treatment and bleached by sodium hypochlorite (NaClO) and buffer. Second method, cellulose was extracted using peroxyacetic acid delignification and bleached the sample in acidified pH 3 hydrogen peroxide solution. From X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) data’s, it is proven that both samples of cellulose have shown cellulose I structure.

•Vaterite calcium carbonate as adsorbent for removal of Congo red.•Ethylene glycol (EG) is a stabilizer to produce spherical vaterite CaCO3.•Vaterite CaCO3has a positive surface charge at pH 5–9.•Vaterite CaCO3adsorbed up to 16.6mg/g of Congo red from aqueous solution.

Two-dimensional (2D) materials have great potential for various applications due to their unique electrochemical properties. In this study, we successfully synthesized molybdenum disulfide-reduced graphene oxide (MoS2-rGO) composites using the microwave-assisted method at 140 °C for 30 min with different concentrations of ammonium tetrathiomolybdate, ((NH4)2MoS4). Morphology analysis of the composites revealed the distribution of Mo on the rGO sheets. The MoS2-rGO electrode synthesized with 0.01 M (NH4)2MoS4exhibited a tremendous specific capacitance of 561.3 F g−1at current density 0.8 A g−1along with a capacitance retention of 92% after 10,000 cycles. Used in an asymmetric supercapacitor device, it demonstrated energy and power densities of 39.90 Wh kg−1and 800 W kg−1, respectively. These results suggest MoS2-rGO as an outstanding potential candidate for supercapacitor electrodes in energy storage applications.

This study aims to optimize the conditions for mannose production from deproteinated palm kernel cake (DPKC) via acid hydrolysis using fumaric acid. In order to convert DPKC into mannose, three important factors, i.e., reaction temperature (156 224 °C), acid concentration (0.02 0.08 N) and reaction time (4.96 89.04 min) were considered. The maximum mannose yield, 53.37%, was achieved at 188 °C, 0.06 N fumaric acid and reaction time of 51 min 32 s with the determination coefficient (R2) value of 0.9667.

•Cocoa pod husk (CPH) as adsorbent for dye removal.•Alkaline (NaOH) treatment creates porosity on the CPH.•NaOH-treated CPH adsorbed up to 181.8mg/g of methylene blue.

Phenol formaldehyde (PF) resin prepared from phenol-liquefied empty fruit bunch (EFB) fibres was blended with polypropylene (PP) using a co-rotating twin-screw extruder. The effects of the PF content (10, 20, 30 and 40 wt.%) blended with PP on the properties of the PP/PF board were investigated. SEM images depicted the formation of spherical protuberances and voids in the PP/PF board with the increasing PF content. The size of the protuberances was also increased with the PF content. The formation of void could be due to the release of water, ammonia and formaldehyde during the blending and hot-press processes. The density, moisture content and maximum water absorption of the PP/PF board increased with the increase of PF content. The TG curves of the PP/PF boards revealed that the PF and PP in the PP/PF board decomposed at different temperature ranges, i.e., 200–420 and 425–480 °C, respectively. The addition of PF to PP reduced the activation energy of the first stage thermal decomposition of the PP/PF boards. The addition of 10 wt.% PF was the optimum content to produce PP/PF board with optimum mechanical properties.

This study was carried out to determine the suitability of sago starch as a paper additive. The basic properties (i.e., pH, viscosity, and solid content) of the 5% weight over volume basis of unmodified and modified sago starch (sago starch blended with acrylamide, sago starch grafted with acrylamide in an acidic and adjusted to alkaline conditions) were determined. The starches were then used to coat laboratory handsheets made from recycled pulp fibers. The incorporation of acrylamide into sago starch through grafting significantly reduced the viscosity of the solution. Generally, coating the handsheets with unmodified sago starch significantly improved some properties as compared to the uncoated handsheets. Among the three types of sago starch modification methods, blending gave superior performance when coated on the handsheets, except for smoothness and air permeance, due to insufficient curing shown by the micrographs. FTIR spectra showed that the interactions between the blended acrylamide–starch solutions and the pulp fiber were weak. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 154–158, 2004

Oil palm fiber empty fruit bunch (EFB) was chemically treated with benzyl chloride (bz-efb) and ethylene oxide (E-efb) at different reaction temperatures (100 and 110°C for bz-efb; 55, 85, and 92°C for E-efb). The SEM micrographs of bz-efb and E-efb samples showed tremendous changes in morphological structure such as plastic properties as the reaction temperature was increased. The crystallinity (by XRD) and Tg of the reacted fibers were found to decrease as the reaction temperature increased. The FT-IR of the reacted samples show that the chemical reactions have taken place between cellulose hydroxyl groups and bz-efb and E-efb, respectively. © 2001 John Wiley & Sons, Inc. Adv Polym Techn 20: 289–295, 2001

Oil palm fiber empty fruit bunch (EFB) was chemically treated with benzyl chloride (bz‐efb) and ethylene oxide (E‐efb) at different reaction temperatures (100 and 110°C for bz‐efb; 55, 85, and 92°C for E‐efb). The SEM micrographs of bz‐efb and E‐efb samples showed tremendous changes in morphological structure such as plastic properties as the reaction temperature was increased. The crystallinity (by XRD) and Tgof the reacted fibers were found to decrease as the reaction temperature increased. The FT‐IR of the reacted samples show that the chemical reactions have taken place between cellulose hydroxyl groups and bz‐efb and E‐efb, respectively. © 2001 John Wiley & Sons, Inc. Adv Polym Techn 20: 289–295, 2001

Self-adhesive carbon grains (sacg1) and heat-treated kraft lignin (htkl) were prepared from the oil palm empty fruit bunch, a potential precursor for carbon products due to its large availability from palm oil mills, and sacg was prepared from cellulose (sacg2). Pellets were prepared from mixtures of sacg1 and htkl, as well as sacg1 and sacg2, with varying percentages of htkl (Phtkl%) and sacg2 (Psacg2%). After carbonization up to 1000°C, the measured electrical conductivities, ? (?·cm)-1, of the respective pellets follow the equations ?=4.13Phtkl+2.43 and ?=0.53Psacg2+2.55, respectively, indicating that htkl has improved in its conducting phase compared to sacg2.