Mesocarp Fiber Research Articles

Effect of acetic acid concentration on obtaining cellulose acetate from oil palm mesocarp fibers (Elaeis guineensis Jacq.)

This work aimed to produce cellulose acetate from the mesocarp fibers of palm oil treated with sodium hydroxide (MFA) and bleached with sodium chlorite. Cellulose acetate was obtained from the different materials by homogeneous acetylation in the mass proportions of: 1:5, 1:10 and 1:15 (acetic acid), 1:15 (acetic anhydride) and 1:0.1 (sulfuric acid). The degree of substitution was determined by chemical methods and by 1H-NMR. The cellulose acetate obtained from the combination of alkaline treatments followed by bleaching showed degree of substitution of 2.81 (CAAB5), 3.02 (CAAB10) and 3.07 (CAAB15), corresponding to yield values (w/w) of 50.45%, 65.5% and 97.21%. Based on the analysis of the results, we can say that the amount of acetic acid and the type of treatment used in the fibers of the mesocarp of oil palm directly influenced the quality and yield of cellulose acetate, with CAAB15 being the best reaction condition.

Deep eutectic solvent pretreatment of oil palm biomass: Promoted lignin pyrolysis and enzymatic digestibility of solid residues.

Herein, choline chloride/oxalic acid (ChCl/OA) and choline chloride/oxalic acid/ethylene glycol (ChCl/OA/EG) pretreatments of oil palm empty fruit bunches (EFB) and mesocarp fibers (MSF) were conducted to achieve protection of the lignin structure, while improving the enzymatic efficiency of the solid residues. Under the operating conditions of 90 °C and 6 h, ChCl/OA/EG demonstrated a higher lignin extraction selectivity and obtained solid residues with higher hemicellulose content compared to ChCl/OA. The digestibility of glucan and xylan in solid residues obtained using ChCl/OA/EG achieved 98.56 % and 95.63 %, respectively, for EFB and 75.95 % and 88.60 %, for MSF. Uncondensed lignin enriched with 71.79-81.61 % of β-O-4 bonds was obtained from EFB and MSF using ChCl/OA/EG. 2D HSQC NMR and the density functional theory calculation confirmed that substituting the lignin Cα position by ethylene glycol changed the local potentials of the β-O-4 bonds, impeding the attack of protons (H+). The higher β-O-4 linkage content in ChCl/OA/EG-Ls led to the formation of several oxygenated alkyl methoxy phenols and alkyl methoxy phenols were promoted during the pyrolysis. Moreover, molecular dynamics simulations showed that the main factor affecting lignin extraction and dissolution in this study was the diffusion coefficient of lignin in DESs.

Effects of Incorporating Oil Palm Mesocarp Fiber as Partial Replacement of Fine Aggregate on the Sound Absorption Performance and Mechanical Properties of Standard Concrete

Effects of Incorporating Oil Palm Mesocarp Fiber as Partial Replacement of Fine Aggregate on the Sound Absorption Performance and Mechanical Properties of Standard Concrete

Assessment of self-compacting lightweight concrete: preparation of eco-friendly fiber content on mechanical and durable characteristics

Abstract In recent years, a growing focus has been on creating eco-friendly concrete alternatives, garnering increased attention and support. Using natural fibers in the construction industry will minimize the exploitation of natural raw materials and promote sustainability in the construction industry. This work aims to investigate the influence of palmyra fruit mesocarp fiber (PFMF), Polyolefin fiber (PF), and glass fiber (GF) on the production of self-compacting concrete (SCC). The fiber content was used in three ratios, 1, 1.5, and 2%, as an alternative to fine aggregate. This research was conducted in two phases. In the first phase, a preliminary investigation was carried out to find the maximum adding percentage of fiber content in the successful production of SCC. The mechanical characteristics (compressive, split tensile, and flexural strength) and durability (water absorption, Acid attack, and ultrasonic pulse velocity) were evaluated. The second phase incorporates the fresh characteristics (T500 and slump flow). Adding 1.5%(PFMF/PF/GF) with 10% SF in SCC significantly enhanced the mechanical and durability properties. The compressive, splitting tensile strength, and flexural strength at 28 days increase to 4.30 MPa, 120 MPa, and 4.3 MPa compared to SCC. Scanning electronic microscopic (SEM) and X-ray diffraction (XRD) analysis was performed to evaluate the microstructure of concrete samples. Overall, the incorporation of up to 1.5% as a replacement of fine aggregate in manufacturing fiber-blended SCC mixtures can be recommended.

Supercritical CO2 as a green technology for carotenoids-rich virgin palm oil production: Process optimization, kinetics and thermodynamics modeling

The experimental conditions of supercritical carbon dioxide (scCO2) extraction of virgin palm oil (VPO) from oil palm mesocarp fiber (OPMF) were optimized using the Response Surface Methodology (RSM). Results showed that a maximum of 28.68 % of VPO extraction was obtained at the optimal experimental conditions of scCO2 extraction: pressure of 31 MPa, temperature of 340 K, and extraction time of 80 min. The second-order rate equation, Arrhenius equation and Eyring theory were employed to assess the kinetics behaviour, activation energy and thermodynamics behaviour of scCO2 extraction of VPO from oil palm mesocarp fiber. The lower activation energy value (12.17 kJ/mol) of scCO2 for the extraction of VPO from OPMF indicates that the scCO2 extraction technology is less dependent on temperature during the extraction of VPO from OPMF. The physicochemical properties and fatty acids compositions analyses reveal that the scCO2 extracted VPO contains high carotenoids content (982 μg/g), low free fatty acids content (0.31 wt%), higher oxidative stability and higher unsaturated fatty acids content.

Mechanical Performance of a Hot Mix Asphalt Modified with Biochar Obtained from Oil Palm Mesocarp Fiber

A recently used material that shows environmental and technical advantages for use as an asphalt binder modifier is biochar (BC). Different biomasses can be converted into BC by pyrolysis. One agro-industrial biomass that is abundant in copious quantities is oil palm mesocarp fiber (OPMF) obtained from African palm cultivation. In the present study, the use of a BC obtained from OPMF (BC-OPMF) as a modifier of asphalt binder (AC type) to produce a hot mix asphalt (HMA) was evaluated. This type of BC has not been investigated or reported in the reference literature as a binder and/or asphalt mix modifier. Initially, AC was modified with BC in three ratios (BC/AC = 5, 10, and 15%, with respect to mass) to perform penetration, softening point, and rotational viscosity tests; rheological characterization at high and intermediate temperatures; and scanning electron microscope (SEM) visualization. Based on this experimental phase, BC/AC = 10% was chosen to manufacture the modified HMA. Resistance parameters under monotonic loading (stability—S, flow—F, S/F ratio of the Marshall test, and indirect tensile strength in dry—ITSD and wet—ITSC conditions) and cyclic loading (resilient modulus, permanent deformation, and fatigue resistance under stress-controlled conditions) were evaluated on the control HMA (AC unmodified) and the modified HMA. Additionally, the tensile strength ratio (TSR) was calculated to evaluate the resistance to moisture damage. Abrasion and raveling resistance were evaluated by performing Cantabro tests. BC-OPMF is shown to be a sustainable and promising material for modifying asphalt binders for those seeking to increase stiffness and rutting resistance in high-temperature climates, resistance to moisture damage, raveling, and fatigue without increasing the optimum asphalt binder content (OAC), changing the volumetric composition of the HMA or increasing the manufacturing and construction temperatures.

Production of natural cellulose-based microfibres, from oil palm mesocarp fibres and pineapple leaf wastes, as porous supports for further applications

Natural cellulose-based microfibers were obtained through an economical and environmentally sustainable process called alkaline-peroxide purification, from the waste products of oil palm mesocarp fibres (OPMF) and pineapple leaves (PL), with the intention of creating porous, biodegradable, biocompatible, and non-toxic solid supports for use in future processes. The extracted microfibres were then taken through microscopic, spectroscopic and thermal characterisation to establish their cellulosic nature. The scanning electron microscopic (SEM) images of the bleached microfibres (B-OPMF and B-PLF) were cleaner, smoother and porous as compared with that of the unrefined fibres (Ur-OPMF and Ur-PLF). The bleached fibres (B-OPMF and B-PLF) exhibited peaks of C and O, which are indicative of pure cellulose, in the energy-dispersive X-ray spectroscopy (EDS) analysis. The FTIR spectral analysis of the extracted cellulose-based fibres (B-OPMF and B-PLF) exhibited peaks that were similar in composition to the reference cellulose (P-GB). For the thermogravimetric analysis (TGA) analysis, the maximum weight degradation in the reference cellulose (P-GB), occurred at 363.11 °C, in the bleached palm fibres (B-OPMF) at 334.55 °C and in the bleached pineapple leaf fibres (B-PLF) at 375.68 °C which, corresponds to cellulose decomposition. The differential scanning calorimetry (DSC) test verified the microfibers' thermally induced transitions. Therefore, these cellulose-based microfibres could be applied as functionalised microfibre supports for future applications.

COMPARATIVE ANALYSIS OF CURRENT BIOMASS UTILISATION BY PALM OIL MILLS IN PENINSULAR MALAYSIA

Oil palm biomass, which includes empty fruit bunches (EFB), mesocarp fibres (MF), palm kernel shells (PKS), and palm oil mill effluent (POME), are no longer seen as low-value residue, but as valuable economic resources that may contribute positively to national wealth. These oil palm biomasses can be converted into high value-added products, which can in turn generate additional revenue for the country. This study aims to identify the current biomass utilisation by palm oil mills in Peninsular Malaysia and examine the economic viability of biomass products generated by these mills across different categories. This study uses primary data obtained through a census of all 242 Malaysian Palm Oil Board-licensed palm oil mills in Peninsular Malaysia. The data were analysed using descriptive analysis and independent samples t-test. The study found that incineration is the most profitable approach for EFB, followed by selling EFB to other parties. However, due to environmental regulation and the lack of market for EFB, most of the resources (62.4%) were either returned to plantations or sent to landfills. In addition, 92.4% of MF generated were utilised for electricity generation through in-house boilers and this alternative has been proven to provide maximum profit to palm oil mills. The study also found that although selling PKS to other parties was proven to provide better profits to the palm oil mills, the PKS were mostly utilised for electricity generation through in-house boilers. Lastly, for the sludge from POME, there was no significant difference in the utilisation of the sludge, either if it was used for plantations or sold to other parties.

Investigating process parameters to enhance (hemi)cellulolytic enzymes activity produced by Trichoderma reesei RUT-C30 using deoiled oil palm mesocarp fiber in solid-state fermentation

This study investigates the synthesis of (hemi)cellulolytic enzymes, including endoglucanase (CMCase), xylanase, and β-glucosidase, employing Trichoderma reesei RUT-C30 and deoiled oil palm mesocarp fiber (OPMF) through solid-state fermentation (SSF). The objective was to determine the optimal process conditions for achieving high enzyme activities through a one-factor-at-a-time approach. The study primarily focused on the impact of the solid-to-liquid ratio, incubation period, initial pH, and temperature on enzyme activity. The effects of OPMF pretreatment, particularly deoiling and fortification, were explored. This approach significantly improved enzyme activity levels compared to the initial conditions, with CMCase increasing by 111.6 %, xylanase by 665.2 %, and β-Glucosidase by 1678.1 %. Xylanase and β-glucosidase activities, peaking at 1346.75 and 9.89 IU per gram dry substrate (GDS), respectively, under optimized conditions (1:4 ratio, pH 7.5, 20 °C, 9-day incubation). With lower moisture levels, CMCase reached its maximum activity of 227.84 IU/GDS. The study highlights how important it is for agro-industrial byproducts to support environmentally sustainable practices in the palm oil industry. It also emphasizes how differently each enzyme reacts to changes in process parameters.

Effect of Adding Oil Palm (Elaeis guineensis Jacq.) Mesocarp Fibers to Cement Composites

The construction industry's ongoing pursuit of eco-friendly materials has led to extensive research into fiber cement composites (FCC), particularly those utilizing natural fibers such as oil palm (Elaeis guineensis Jacq.) mesocarp fiber (OPMF) from Peru. This study examined the physical, mechanical, and chemical effects of adding different proportions of OPMF (0, 3, 6, and 9%) in manufacturing FCCs. This addition resulted in reduced values regarding density, porosity, and modulus of rupture, as well as in increased moisture content and thickness reduction. The FCC containing 3% OPMF exhibited the most favorable performance thanks to its higher density and its lower water absorption and porosity when compared to the control board (0%-OPMF). Micro-images revealed minor microcracks and interfacial gaps, indicative of debonding, which compromises the properties of the FCC. Furthermore, an infrared spectrum analysis demonstrated an increase in hydroxyl group vibrations with an increased fiber proportion.

Efficient methane production from agro-industrial residues using anaerobic fungal-rich consortia.

Anaerobic digestion (AD) emerges as a pivotal technique in climate change mitigation, transforming organic materials into biogas, a renewable energy form. This process significantly impacts energy production and waste management, influencing greenhouse gas emissions. Traditional research has largely focused on anaerobic bacteria and methanogens for methane production. However, the potential of anaerobic lignocellulolytic fungi for degrading lignocellulosic biomass remains less explored. In this study, buffalo rumen inocula were enriched and acclimatized to improve lignocellulolytic hydrolysis activity. Two consortia were established: the anaerobic fungi consortium (AFC), selectively enriched for fungi, and the anaerobic lignocellulolytic microbial consortium (ALMC). The consortia were utilized to create five distinct microbial cocktails-AF0, AF20, AF50, AF80, and AF100. These cocktails were formulated based on varying of AFC and ALMC by weights (w/w). Methane production from each cocktail of lignocellulosic biomasses (cassava pulp and oil palm residues) was evaluated. The highest methane yields of CP, EFB, and MFB were obtained at 337, 215, and 54 mL/g VS, respectively. Cocktails containing a mix of anaerobic fungi, hydrolytic bacteria (Sphingobacterium sp.), syntrophic bacteria (Sphaerochaeta sp.), and hydrogenotrophic methanogens produced 2.1-2.6 times higher methane in cassava pulp and 1.1-1.2 times in oil palm empty fruit bunch compared to AF0. All cocktails effectively produced methane from oil palm empty fruit bunch due to its lipid content. However, methane production ceased after 3 days when oil palm mesocarp fiber was used, due to long-chain fatty acid accumulation. Anaerobic fungi consortia showed effective lignocellulosic and starchy biomass degradation without inhibition due to organic acid accumulation. These findings underscore the potential of tailored microbial cocktails for enhancing methane production from diverse lignocellulosic substrates.

Oil palm waste-derived adsorbents for the sequestration of selected polycyclic aromatic hydrocarbon in contaminated aqueous medium

Carbonaceous adsorbents were synthesized from palm kernel shell and palm mesocarp fiber for the adsorption of phenanthrene (PHE) and the highly carcinogenic-benzo(a)pyrene (BaP). The structure and properties of the activated biochar were characterized using standardized analytical tools. The microscopic examinations carried out with SEM and BET results revealed mesoporous structures and interstitial spaces in the activated samples (AB-PKS and AB-PMS). Powder X-ray diffraction (PXRD) results showed that prepared sorbents are amorphous and that activation affected the amorphous cellulose on the surface of the microfibrils which led to a decrease in the intensity of some peaks. Fourier-transform infrared spectroscopy (FTIR) affirms the availability of surface moieties that may promote polycyclic aromatic hydrocarbon (PAH) removal or decontamination of aqueous media. The sorption isotherm and effect of pH on the adsorption of PHE and BaP onto the activated palm kernel shell (AB-PKS) and activated palm mesocarp fiber (AB-PMF) were investigated. The isotherm studies and error analysis (SSE and R2) confirm that the Freundlich model best fits experimental results for AB-PMF; while, the Langmuir model best describes AB-PKS sorption of BaP and PHE, respectively. The optimal removal efficiency for PHE was between 84 and 100% while that of BaP was between 68 and 87% with maximum adsorption capacity (qmax) of 19.38–21.98 mg/g and 1.24–13.26 mg/g, respectively. The optimum pH condition for removing PHE is less than 7 and above 7 for BaP. Therefore, the conversion of waste materials to useful sorbents, as well as preliminary adsorption test results obtained suggests a cleaner and cost-effective pathway for waste management and water treatment.

Assessing the efficacy of utilizing biochar derived from oil palm biomass as a planting medium for promoting the growth and development of oil palm seedlings

The recent adoption of biochar in Malaysia's oil palm industry offers numerous benefits, including soil enhancement, resource efficiency improvement, pollution remediation, and greenhouse gas mitigation. With approximately 66.15% of agricultural land dedicated to oil palm cultivation, a substantial amount of biomass, mainly from empty fruit bunch (EFB) and mesocarp fibre (MF), is generated. This study focused on carbonizing MF and EFB at temperatures ranging from 580 to 695 °C to produce biochar. The assessment of biochar's effectiveness as a planting medium in nurseries revealed significantly accelerated growth rates in seedlings cultivated in a composite of biochar and soil. At 8 months-after-treatment (MAT), the BMF-75 treatment showed remarkable growth enhancements, with the highest increase in height (64.9%), number of leaflets (60.5%), and girth size (55.3%) compared to the initial values at 3 MAT, indicating its effectiveness in promoting growth in oil palm seedlings. Additionally, compared to the control group, the biochar-mixed media resulted in favourable outcomes regarding the assimilation of both macro- and micro-nutrients. For instance, nitrogen uptake increased by 2.7% with BMF-50, magnesium by 25.2%, phosphorus by 24.1% with BEFB-75, calcium by 36.8% with BMF-75, chlorine by 10.5% with BMF-50, iron by 25.5% with BEFB-25, copper by 20.1% with BMF-25, and zinc by 6.3% with BMF-25. Additionally, biochar-treated soil exhibited higher organic carbon content, improved cation exchange capacity (CEC), enhanced nitrogen retention with greater biochar proportions, and likely improved soil fertility due to biochar's porous structure. Further potential research can be explored to investigate its long-term effects on oil palm plantation.

Pyrolysis of oil palm trunk biomass using a fixed bed reactor to produce raw material for bio-carbon black

The abundance of palm oil plantation waste in Indonesia can be utilized as a raw material for making carbon black, which currently relies on fossil fuel-based raw materials. Out of the five types of palm oil biomass waste, including empty fruit bunches (EFB), palm kernel shells (PKS), palm mesocarp fibers (PMF), oil palm fronds (OPF), and oil palm trunks (OPT), one will be chosen as the raw material for carbon black production. Palm oil biomass waste typically has a relatively high ash content. To reduce the ash content, the biomass must first undergo pyrolysis to transform it into pyrolysis oil. The higher the carbon content and the lower the oxygen content, the more the pyrolysis oil meets the criteria for replacing crude oil. Among the criteria mentioned, the lowest ash content is found in palm kernel shells (1.4%). The highest carbon content is in palm trunks (55.8%), while the lowest oxygen content is also in palm kernel shells (34.5%). Palm kernel shells are the best palm oil biomass that can be used as a raw material for carbon black. However, because palm kernel shells are commonly used as boiler fuel, the second choice is palm trunks due to their high carbon content. Pyrolysis experiments were conducted using palm trunk biomass to produce bio-oil, which would be further processed into carbon black. The palm trunks were divided into three parts: outer trunk, middle trunk, and core trunk. The biomass size was also varied, with sizes of 20 mesh and 40 mesh. The pyrolysis process used a fixed bed reactor with a heating rate of 3°C/minute, reaching a pyrolysis temperature of 600°C, and maintaining that temperature for 1.5 hours. The highest yield of bio-oil obtained was from the outer trunk with a biomass size of 40 mesh (36.8%). Similarly, for a size of 20 mesh, the highest yield was also from the outer trunk (35.7%).

Production of oil palm mesocarp fiber-based hydrogel using selected cross-linking acids

Abstract Over the years, studies showed that hydrogels can be produced through synthetic route to overcome the limitations in obtaining natural-based hydrogels. Biomass resources offer potential alternatives as renewable feedstocks due to their outstanding biodegradability and biocompatibility. Oil palm mesocarp fiber (MF) is the biomass residue obtained after the pressing of palm fruits during palm oil extraction. There is approximately 11 % MF generated from palm fruits after oil extraction. However, the applications of MF are limited. This study aimed to investigate the development of hydrogels from holocellulose MF instead of commonly used cellulose which involving several pretreatment steps, through acid cross-linkers. Holocellulose MF was selected as polymer for chemical cross-linking with two inexpensive and nontoxic hydrophilic organic acids, citric acid and acetic acid for hydrogel production. Comparison study was carried out to evaluate the physicochemical properties, and degree of swelling, as well as gel content in different media for both acids in the production of hydrogel from holocellulose MF. Results indicated that the optimum concentrations of citric acid and acetic acid for gel content and degree of swelling were 5 M and 2 M, respectively. Both optimized hydrogels exhibited comparable profiles in terms of morphology, thermal stability and functional groups, in addition to showing similar degree of swelling profile in different media, i.e., salt solution, acidic, neutral to alkaline, implying their distinctive characteristics. In summary, holocellulose MF is suitable for the production of hydrogel with citric acid and acetic acid as crosslinkers for different desired applications.

Effects of oil palm mesocarp fibers on the physical and mechanical properties of expansive soils

Palm fiber is one of the favorable materials used in stabilization of soft soil in geotechnical engineering projects, nowadays due to its sustainability, less damage of environment, biodegradability, availability and cost-effectiveness in a context of widespread appeal to the world for return to nature by protecting the earth. On the other hand, expansive soils are renowned for their swelling-shrinkage property and these volumetric changes resultantly cause huge damage to civil infrastructures. Likewise, subgrades consisting of expansive soils instigate serviceability failures in pavements across various regions worldwide. This paper presents results of the laboratory evaluation of expansive soils stabilized with oil palm mesocarp fiber (OPMF), with a view to determine its suitability as flexible pavement construction material. The mixtures were subjected to British Standard heavy (modified Proctor) compaction energy to determine their strength characteristics. The samples were subjected to different tests to ascertain their index properties. Varying proportions of OPMF from 1% to 4% were incorporated into the soil samples and the effects were observed based on compaction and California Bearing Ratio (CBR) results. The control samples without inclusion of OPMF achieved the highest Maximum Dry Densities (MDD), the MDDs reduced linearly as the OPMF content increased. Consequently, the CBR values decreased with increase in OPMF. The reduction in MDD ranged from 20.28g/cm3, 18.5 g/cm3, 15.65 g/cm3, 12.53 g/cm3 as the OPMF increased from 1%, 2% to 3%, 4%. and the optimum moisture content remained almost unaffected due to high-absorbent nature of the fibers. With the inclusion of the OPMF, the CBR value under soaked conditions dropped from 5% to 1.8% rendering them very unsuitable for pavement subgrade. It was concluded that the presence of fiber depreciated the engineering properties of the earth materials. Direct application of OPMF in any part of road pavement has been dissuaded.

Effect of ultrasound-advanced oxidation processes for pretreatment of oil palm mesocarp fiber for cellulose extraction

Effect of ultrasound-advanced oxidation processes for pretreatment of oil palm mesocarp fiber for cellulose extraction

Influence of oil palm mesocarp fiber on physical properties of fabricated plaster of paris ceilings

Influence of oil palm mesocarp fiber on physical properties of fabricated plaster of paris ceilings

Antioxidant and antimicrobial activities of lignin-derived products from all steam-exploded palm oil mill lignocellulosic biomass waste

BackgroundSteam explosion pretreatment has been proven to be an effective treatment for breaking down the recalcitrant character of lignin–carbohydrate complexes (LCC) in lignocellulosic biomass. This study investigated the production of lignin-derived products from steam-exploded palm oil mill lignocellulosic biomass waste (POMLBW), that is, empty fruit bunches (EFB), kernel shells (KS), and kernel fibers (KF), also known as mesocarp fibers. Steam explosions cause lignin depolymerization, which forms various polyphenols. The low average molecular weight of the steam-exploded lignin-derived products and their antioxidant activities could potentially enhance their antimicrobial activities.MethodsPOMLBW was steam-exploded with various degrees of severity factors (R0: 4.03, 4.91, 5.12, 5.35, and 5.65). Steam-exploded POMLBW produces lignin-derived products such as low-molecular-weight lignin (LML) and water-soluble lignin (WSL). Antioxidant activity was evaluated using 0.5 mM 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. Polyphenol content was evaluated using the Folin–Ciocalteu method. The antimicrobial activity was evaluated using an agar diffusion assay with Gram-positive and Gram-negative bacteria, and the thermal characteristics were evaluated using differential scanning calorimetry and thermogravimetric analysis.ResultsWSL and LML resulted in high radical scavenging activity (RSA) of approximately 95% and 80%, with 0.25 g/L and 0.5 g/L of EC50, where the polyphenol amount was 242–448 mg/g (catechin eq.) and 20–117 mg/g (catechin eq.) under all LML and WSL conditions, respectively. The steam-exploded POMLBW had an average molecular weight of 1589–2832 Da, and this condition, including high RSA and polyphenol amounts, was responsible for the high antimicrobial activities of LML against both Gram-positive (Salmonella enterica, Pseudomonas aeruginosa, and Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria. Additionally, the thermal properties investigations revealed that the glass transition temperature was 80–90 °C (Tg), the melting temperature (Tm) was 338–362 °C, and the start temperature was 101–128 °C at the beginning of mass loss.ConclusionsThese results show that the lignin-derived product from steam-exploded POMLBW has the potential for antioxidant (LML and WSL) and antimicrobial (LML) applications with good thermal resistance.Graphical

Manual wooden low-pressure briquetting press: An alternative technology of waste biomass utilisation in developing countries of Southeast Asia

Although briquetting is an appropriate technology for the production of renewable energy, its widespreadness in Southeast Asia is limited. Especially due to the high initial investments and energy consumption of a high-pressure briquetting press. However, manual low-pressure briquetting presses (operating pressure <5 MPa) can represent a relevant alternative, regarding to their ease of use and modest energy consumption. The aim of the present research was to develop and verify a manual wooden low pressure briquetting press with a square-shaped pressing chamber, piston and a single lever as a pressing unit. In practice, press was designed, manufactured, and verified by successful bio-briquette samples production. Four different feedstock mixtures were prepared from coconut mesocarp fibre (CF), bamboo skin (BS), pineapple leaves (PL), sugarcane bagasse (SB); each mixed with external binding agent (wastepaper) in biomass:binder ratios of 1:1 and 2:1. The achieved bulk density ρ ranged from 204.30 ± 15.73 kg m−3 for 1:1 feedstock mixtures and 199.31 ± 23.13 kg m−3 for 2:1 feedstock mixtures. The press efficiency, feasibility and practicability were positively evaluated within their possible utilisation in rural areas of developing countries. The importance of research increases constantly due to the worldwide need for a transition from fossil fuels to renewable energy sources, proper waste management, and reduction of environmental and health risks related to improper treatment of waste materials. The final idea of the article contributes to the development of the sector of clean green energy production, simultaneously with raising awareness about sustainable technologies for proper waste management within the wide public.