Search Results (29)

The growing demand for sustainable, decentralized energy solutions has heightened interest in biomass-based technologies for rural applications. In Mexico, the expansion of oil palm cultivation in humid tropical regions has generated large quantities of agro-industrial residues that remain largely underutilized. This review analyzes the potential of oil palm residues as feedstock for small-scale thermochemical conversion, with a particular focus on gasifier stove technologies. Key residues, including empty fruit bunches, mesocarp fiber, and palm kernel shells, exhibit favorable physicochemical properties, including adequate calorific values and high volatile matter content, which support their suitability for gasification processes. However, challenges related to moisture content, ash composition, and tar formation may affect system performance and require appropriate pre-treatment and operational control. Gasifier stoves, especially fixed-bed and top-lit updraft (TLUD) configurations, represent a viable solution for decentralized energy generation in rural settings, improving combustion efficiency and reducing emissions compared to traditional biomass use. Despite their potential, current bioenergy policies in Mexico remain primarily focused on large-scale biofuel production, limiting the deployment of small-scale technologies. Overall, oil palm residues constitute a promising feedstock for gasifier stove applications, although their successful implementation depends on feedstock optimization, appropriate stove design, and the development of policy frameworks that support decentralized bioenergy systems. Full article

Palm oil waste (POW) is generated during the production of palm oil, and a large quantity of this waste often travels to landfills for disposal. This review aims to provide a comprehensive understanding of the circular economy approach to sustainable engineering and environmental applications of POW, including its generation, disposal concerns, challenges, and prospects. This review provides an overview of the features, composition, and prospective applications of several POWs, including palm oil clinkers (POCs), palm oil fuel ashes (POFAs), palm oil kernel shells (POKSs), and palm oil fibres (POFs). Furthermore, this overview describes the different applications that POW has found, such as sustainable construction materials, renewable energy production, and environmental remediation. Moreover, this review discusses the leaching and risk assessment of POW. The overview also discusses the circular economy implications of using POW. The results showed that while some wastes are reused and recycled, a good quantity are still discarded in environmentally harmful ways. With this overview of a wide circular economy approach to the sustainable use of POW, there will be a rallying call to experts and researchers to identify research gaps that could contribute to the sustainable use of POW. The results of this overview of the sustainable engineering and environmental applications of POW with a circular economy approach indicate that cleaner production technologies and better environmental sustainability of the palm oil industry are feasible through proper waste management, renewable energy generation, resulting in minimal environmental impacts. Furthermore, this analysis will be very useful in providing tools to engineers, environmentalists, and other relevant stakeholders to enable the efficient and sustainable use of POW in the global circular economy. Full article

This study analyzes the valorization of oil palm biomass residues within the framework of industrial symbiosis (IS), emphasizing their role in circular economy strategies and sustainable industrial development. Through a systematic literature review and snowball sampling, 156 articles indexed in Scopus and Web of Science were examined, classifying evidence by country, type of residue, derived products, economic sector (ISIC Rev. 4), and technological approach. The results show a strong geographical concentration of IS experiences in Asia, particularly Malaysia, Indonesia, and Thailand, where residues such as empty fruit bunches (EFB), palm kernel shells (PKS), oil palm mesocarp fibers, palm oil mill effluent (POME), and oil palm trunks (OPT) are integrated into processes for bioenergy, biochemicals, composite materials, construction products, biochar, and bioplastics. In contrast, applications in Latin America and Africa remain incipient, with high potential but limited industrial implementation due to infrastructural and regulatory gaps. Technological trends point toward thermo-chemical and biological conversion routes (pyrolysis, gasification, hydrothermal carbonization, anaerobic digestion), development of advanced materials and catalysts, and the emergence of integrated biorefinery models supported by computational optimization tools. The analysis highlights that palm biomass residues, far from being an environmental liability, constitute strategic resources for low-carbon value chains. However, scaling IS initiatives requires clear public policies, economic incentives, and stronger coordination between industry, government, and academia. The study provides a structured overview of current knowledge, identifies research gaps, and outlines future directions for leveraging oil palm residues as a key input for sustainable IS. Full article

Oil palm kernel shell is an abundant agricultural waste generated by the palm oil industry. To achieve sustainable use of this waste, oil palm kernel shells were converted into valuable resources as active biocarbons. A two-stage preparation method involving N₂ pyrolysis, followed by CO₂ activation, was used to produce the active biocarbon. The optimum pyrolysis conditions that produced the largest BET surface area of 519.1 m²/g were a temperature of 600 °C, a hold time of 2 h, a nitrogen flow rate of 150 cm³/min, and a heating rate of 10 °C/min. The optimum activation conditions to prepare the active biocarbon with the largest micropore surface area or the best micropore/BET surface area combination were a temperature of 950 °C, a CO₂ flow rate of 300 cm³/min, a heating rate of 10 °C/min, and a hold time of 3 h, yielding BET and micropore surface areas of 1232.3 and 941.0 m²/g, respectively, and consisting of 76.36% of micropores for the experimental optimisation technique adopted here. This study underscores the importance of optimising both the pyrolysis and activation conditions to produce an active biocarbon with a maximum micropore surface area for gaseous adsorption applications, especially to capture CO₂ greenhouse gas, to mitigate global warming and climate change. Such a comprehensive and detailed study on the conversion of oil palm kernel shell into active biocarbon is lacking in the open literature. The research results provide a practical blueprint on the process parameters and technical know-how for the industrial production of highly microporous active biocarbons prepared from oil palm kernel shells. Full article

Palm oil production generates substantial underutilized biomass wastes, including empty fruit bunches, fiber, palm kernel shells, and palm oil mill effluent (POME). Waste-to-energy systems offer a viable pathway to convert these residues into electricity and fertilizer, supporting circular economy goals and sustainability targets. This study takes an example of palm oil waste from the Indragiri Hulu region in Riau Province in Indonesia. It develops a multi-objective optimization framework to evaluate palm oil mill WtE systems from economic, environmental, and energy output. Three scenarios are analyzed: maximal profit (MP), maximal profit with carbon tax (MPCT), and all waste processing (AWP). The MP scenario favors high-return technologies such as gasification and incineration, leading to significant greenhouse gas emissions. The MPCT scenario favors lower-emission technologies like composting and excludes high-emission, low-profit options such as POME digestion. In contrast, the AWP scenario mandates the processing of all wastes, leading to the lowest profits and the highest emissions among all scenarios. The sensitivity analysis reveals that POME processing is not feasible when electricity prices are below the government-set rate, but becomes viable once prices exceed this threshold. These findings offer valuable insights for companies and policymakers seeking to develop and implement effective strategies for optimal waste utilization. Full article

This work presents an effective design of a strategy to manage biomass waste (empty fruit bunch—EFB, kernel shell, and fiber) available from the processing of oil palm (Elaeis guineensis) in Colombia as a renewable energy source. This type of study is conducted for the first time in the country, and the proposed strategy is structured in four phases. Firstly, an inventory of available biomass waste was prepared based on information from 45 African palm oil companies of the approximately 70 that exist in the country. It was determined that the country had about 2762 kt of available waste (63.64% EFB, 12.55% kernel shell, and 23.81% fiber) for the year 2023. The estimates were conducted using a model that correlates processing capacity, the biomass generated, and the biomass demanded. The validation was performed using national reports. Subsequently, the minimum number (six) of storage centers in Colombia, where the largest amount of biomass can be stored, was determined. The center of gravity method was used to find the geographical location of each bulk storage center (municipality of Aracataca, Agustín Codazzi, San Martín, Puerto Wilches, Castilla La Nueva, and Cabuyaru). The next step was to determine the transportation costs as a decision criterion to select the best bulk storage center. When the required storage capacity does not exceed 211 kt·year⁻¹, Agustín Codazzi is the best option because it has the lowest transportation cost (USD 1.01·t⁻¹). When the storage capacity requirements exceed 211 kt·year⁻¹ but are less than 423 kt·year⁻¹, then Puerto Wilches and/or Aracataca are the best options (transportation cost of USD 1.7·t⁻¹). In all cases, Cabuyaru has the highest costs (USD 6.56·t⁻¹). Finally, an energy potential of 50,196 × 10⁶ GJ·year⁻¹ for the collected biomass was estimated, which makes this kind of waste an environmental alternative that could replace coal in Colombia. Full article

Oil palm kernel shell ash (POFA), a byproduct of the highly cultivated agro-industrial sector in Colombia, has been widely used for its pozzolanic properties, which enhance the mechanical and durability characteristics of concrete. Six POFA samples were analyzed after undergoing drying, cutting, grinding, crushing, and calcination at temperatures ranging from 500 °C to 1000 °C. SEM-EDS/EDX analysis, X-ray fluorescence (XRF), and loss on ignition (LOI) tests were conducted to characterize its pozzolanic potential. The results revealed that the SiO₂ content increased with the calcination temperature, reaching a peak of 76.8% at 1000 °C. However, calcination at 600 °C was identified as the optimal temperature, as it balances impurity removal without inducing the formation of crystalline silica, which would negatively affect the material’s reactivity. Considering the optimal calcination temperature and the high initial LOI values, which exceeded 70% in the first calcination stage, a second calcination was performed on the 500 °C sample by increasing the temperature to 600 °C. This resulted in an LOI of 3.33%, according to ASTM C311 standards for natural pozzolans used in Portland cement concretes. Full article

In recent decades, the global use of ashes derived from agro-industrial by-products, such as oil palm kernel shells, which are widely cultivated in Colombia and other tropical regions of the world, has increased. However, the application of these ashes in engineering remains limited due to their heterogeneity and variability. This study utilized scanning electron microscopy (SEM) to assess the influence of calcination temperatures, ranging from 500 °C to 1000 °C, as well as the physical processes of cutting, grinding, and crushing, on the silica content of the studied ashes. Specifically, the sample labeled M18A-c-m-T600°C-t1.5h-tr1h, which was subjected to a calcination temperature of 600 °C and underwent cutting and grinding before calcination, followed by post-calcination crushing, exhibited the highest silica concentration. Complementary techniques such as X-ray fluorescence (XRF) and X-ray diffraction (XRD), were applied to this sample to evaluate its feasibility as an additive or partial replacement for cement in concrete. XRF analysis revealed a composition of 71.24% SiO₂, 9.39% Al₂O₃, and 2.65% Fe₂O₃, thus, meeting the minimum oxide content established by ASTM C 618 for the classification as a pozzolanic material. Furthermore, XRD analysis confirmed that the sample M18A-c-m-T600°C-t1.5h-tr1h is in an amorphous state, which is the only state in which silica can chemically react with calcium hydroxide resulting from the hydration reactions of cement, forming stable cementitious products with strong mechanical properties. Full article

The palm oil industry (POI) generates significant amounts of waste, including calcium carbonate (CaCO₃) from the clay bath system used for the separation of palm kernels from shells. This CaCO₃ waste is often discarded, leading to environmental issues. However, the CaCO₃ can potentially be reused in the clay bath separation process to improve efficiency and reduce waste. To obtain PKO, the kernel is separated from the palm shell using a clay bath unit, where natural CaCO₃ acts as a decanting agent and adsorbent. This wet separation method, involving a mixture of water and CaCO₃ with a density of 1.12 g/mL, generates substantial amounts of saturated CaCO₃ waste that is often discarded into the environment. Therefore, this research aimed to regenerate oil-bound CaCO₃ waste for reuse as a decanter and adsorbent. Three treatments were tested, with CaCO₃ waste-to-water ratios of 1:1, 1:3, and 1:6, under varying pH levels (8, 10, 11, 12) and temperatures (28 °C, 80 °C, 100 °C). The regeneration process was conducted in an open reactor at 450 rpm with a volume of 0.0054 m³, followed by drying and grinding the waste for analysis. The results showed approximately 75.75% oil removal and CaCO₃ regeneration rates between 94.50% and 99.26%, with an increase in density from 1.687 g/mL to 2.467 g/mL. The efficiency of reusing regenerated CaCO₃ waste is 96.87%. When mixed with 25% natural CaCO₃, the efficiency increases to 99.24%. Additionally, a mixture of 50% regenerated CaCO₃ waste and 50% natural CaCO₃ achieves an average efficiency of 99.46% over five consecutive feed additions. This showed that the reuse of CaCO₃ waste regeneration results for the separation of palm shells and kernels has a high potential for application. These findings suggest that regenerated CaCO₃ waste can be effectively reused, offering a sustainable solution for palm oil mills. Full article

The use of nanoemulsions as encapsulation systems for active ingredients, such as cinnamon oil, has been studied. A surfactant based on polyoxyethylene glycerol esters from coconut/palm kernel oil has been used. The nanoemulsions were obtained by the two most commonly low-energy emulsification methods, the composition inversion phase (PIC) and the temperature inversion phase (PIT) methods. Nanoemulsions were successfully obtained by both methods, with very small droplet sizes (5–14 nm) in both cases, but a greater stability was observed when the PIT method was used. Nanoemulsions were encapsulated by external gelation using two different polysaccharides, alginate or chitosan, dissolved in the continuous phase of the nanoemulsion. Then, the nanoemulsion was dropped into a bath with a gelling agent. To improve the release control of cinnamon oil and avoid the burst effect, beads prepared with one of the polysaccharides were coated with the second polysaccharide and then gelled again. Double gelled beads were successfully obtained, the core with chitosan and the outer layer (shell) with alginate. SEM images showed the morphology of the single beads presenting high porosity. When the beads were coated, the porosity decreased because the second polysaccharide molecules covered the pre-existing pores. The smoother surface was obtained when this second layer was, in turn, gelled. The release patterns at pH = 2 and pH = 7 were studied. It was observed that the double gelled bead provided a more gradual release, but maintained approximately the same amount of final released oil. The release patterns were fitted to the Korsmeyer-Peppas model. The fitting parameters reflected the effect of the different coating layers, correlating with different diffusion mechanisms according to the bead core and shell materials. Full article

Co-pyrolysis is one possible method to handle different biomass leftovers. The success of the implementation depends on several factors, of which the quality of the produced bio-oil is of the highest importance, together with the throughput and constraints of the feedstock. In this study, the fast co-pyrolysis of palm kernel shell (PKS) and woody biomass was conducted in a micro-pyrolyser connected to a Gas Chromatograph–Mass Spectrometer/Flame Ionisation Detector (GC–MS/FID) at 600 °C and 5 s. Different blend ratios were studied to reveal interactions on the primary products formed from the co-pyrolysis, specifically PKS and two woody biomasses. A comparison of the experimental and predicted yields showed that the co-pyrolysis of the binary blends in equal proportions, PKS with mahogany (MAH) or iroko (IRO) sawdust, resulted in a decrease in the relative yield of the phenols by 19%, while HAA was promoted by 43% for the PKS:IRO-1:1 pyrolysis blend, and the saccharides were strongly inhibited for the PKS:MAH-1:1 pyrolysis blend. However, no difference was observed in the yields for the different groups of compounds when the two woody biomasses (MAH:IRO-1:1) were co-pyrolysed. In contrast to the binary blend, the pyrolysis of the ternary blends showed that the yield of the saccharides was promoted to a large extent, while the acids were inhibited for the PKS:MAH:IRO-1:1:1 pyrolysis blend. However, the relative yield of the saccharides was inhibited to a large extent for the PKS:MAH:IRO-1:2:2 pyrolysis blend, while no major difference was observed in the yields across the different groups of compounds when PKS and the woody biomass were blended in equal amounts and pyrolysed (PKS:MAH:IRO-2:1:1). This study showed evidence of a synergistic interaction when co-pyrolysing different biomasses. It also shows that it is possible to enhance the production of a valuable group of compounds with the right biomass composition and blend ratio. Full article

A high load of inorganics in raw lignocellulosic biomass is known to inhibit the yield of bio-oil and alter the chemical reactions during fast pyrolysis of biomass. In this study, palm kernel shell (PKS), an agricultural residue from palm oil production, and two other woody biomass samples (mahogany (MAH) sawdust and iroko (IRO) sawdust) were pretreated with distilled water or an acidic solution (either acetic, formic, hydrochloric (HCl) or sulfuric acid (H₂SO₄)) before fast pyrolysis in order to investigate its effect on the primary products and pyrolysis reaction pathways. The raw and pretreated PKS, MAH and IRO were pyrolysed at 600 °C and 5 s with a micro-pyrolyser connected to a gas chromatograph–mass spectrometer/flame ionisation detector (GC-MS/FID). Of the leaching solutions, HCl was the most effective in removing inorganics from the biomass and enhancing the primary pyrolysis product formed compared to the organic acids (acetic and formic acid). The production of levoglucosan was greatly improved for all pretreated biomasses when compared to the original biomass but especially after HCl pretreatment. Additionally, the relative content of the saccharides was maximised after pretreatment with H₂SO_4, which was due to the increased production of levoglucosenone. The relative content of the saccharides increased by over 70%. This increase may have occurred due to a possible reaction catalysed by the remaining acid in the biomass. The production of furans, especially furfural, was increased for all pretreatments but most noticeable when H₂SO₄ was used. However, the relative content of acids and ketones was generally reduced for PKS, MAH and IRO across all leaching solutions. The relative content of the phenol-type compound decreased to a large extent during pyrolysis after acid pretreatment, which may be attributed to dehydration and demethoxylation reactions. This study shows that the production of valuable chemicals could be promoted by pretreatment with different acid solutions. Full article

The use of biobased heterogeneous catalysts made from agricultural waste for producing biodiesel has gained attention for its potential to create a sustainable and low-cost process. The blending of two or more biomass residues to create more viable biobased catalysts is still in its early stages. In this study, a Biobased Composite Heterogeneous Catalyst (CHC) was made by blending the shells of periwinkle (PWS), melon seed-husk (MSH), and locust bean pod-husk (LBP) at a mixing ratio of 67:17:17 using Simplex Lattice Design Mixture, that was then calcined for 4 h at 800 °C. The chemical, structural, and morphological components of the CHC were characterized via XRF, XRD, SEM-EDX, BET, TGA/DSC, and FTIR to assess its catalytic potential. The CHC was employed to synthesize biodiesel from palm kernel oil, and the process optimization was conducted using the Taguchi approach. The XRF analysis showed that the catalyst had 69.049 of Calcium (Ca) and 9.472 of potassium (K) in their elemental and oxide states as 61.592% calcium oxide and 7.919% potassium oxide. This was also supported by the EDX result, that showed an appreciable value of 58.00% of Ca and 2.30% of magnesium, that perhaps provided the active site in the transesterification reaction to synthesize biodiesel. The morphological and physisorption isotherms via SEM and BET showed mesoporous structures in the CHC that were made up of nanoparticles. A high maximum biodiesel yield of 90.207 wt.% was attained under the optimized process conditions. The catalyst could be reused for up to four cycles, and the biodiesel produced met both ASTM D6751 and EN 14214 standards for biodiesel. This study demonstrates that blending PWS, MSH, and LBP waste materials can produce high-quality biodiesel without the need for additional catalysts. Full article

With the rapid development of the palm oil-related industry, this has resulted in the high production of palm oil waste. The increasing amount of palm oil waste has become an alarming issue in which researchers have carried out studies that this palm oil waste has the potential to be used as a biomass source. Carbon black (CB) is the most preferred reinforcing filler in the rubber industry but it has a disadvantage where CB is carcinogenic and a petroleum-based product. Hence CB is less sustainable. Palm kernel shell (PKS) derived from palm oil waste can be turned into palm kernel shell biochar (PKSBc) which can potentially be a value-added, sustainable biofiller as reinforcement in rubber composites. In this study, PKSBc is hybridized with CB (N660) at different loading ratios to be filled in carboxylated nitrile butadiene rubber (XNBR). This study aims to elucidate the effect of the varying ratios of hybrid CB/PKSBc on the rheological properties, abrasion resistance, and hardness of XNBR composites. In this study, both CB and PKSBc are incorporated into XNBR and were then cured with sulphur. The composites were prepared by using a two-roll mill. Different compositions of hybrid CB/PKSBc were incorporated. The rheological properties and physicomechanical properties, such as abrasion resistance and hardness of the vulcanizates, were investigated. Based on the results, as the loading ratio of PKSBc in hybrid CB/PKSBc increases, the cure time decreases, and the cure rate index increases. The abrasion resistance and hardness values of vulcanizates were maintained by the high loading of PKSBc which was due to the porous structure of PKSBc as shown in the morphological analysis of PKSBc. The pores of PKSBc provided mechanical interlocking to reduce volume loss and maintain the hardness of vulcanizates when subjected to force. With this, PKSBc is proven to be a semi-reinforcing filler that could not only act as a co-filler to existing commercialized CB, but PKSBc could also fully substitute CB as reinforcement in rubber, specifically XNBR as it is able to provide high abrasion resistance and hardness to the rubber composites. This would mean the performance of PKSBc is comparable with CB (N660) when it comes to maintaining the physicomechanical properties of XNBR composites in terms of abrasion resistance and hardness. Therefore, this approach of using eco-friendly filler derived from palm oil agricultural waste (PKSBc) can reduce the abundance of palm oil waste, be a sustainable alternative to act as a co-filler in hybrid CB/PKSBc to decrease the usage of CB, and helps to enhance the quality of existing rubber-based products. Full article

The demand for rubber gloves has significantly increased in both medical and non-medical fields due to the spread of the coronavirus in 2019. It is challenging for rubber glove manufacturing industries to balance the production and demand for the product. Additionally, they must determine techniques to decrease the production costs so as to make rubber gloves more economical for consumers. Generally, natural gas, fossil fuels, and renewable energy sources are used worldwide in the manufacturing of rubber gloves. In addition, Thailand uses biomass energy for rubber glove production, but biomass utilization is not economically friendly. This study used different biomasses as fuel in rubber glove production so as to reduce production costs and make the process more environmentally friendly. Wood chip (WC), palm kernel shells (PKS), and oil palm mesocarp fiber (OPMF) biomass were collected from local regions and used in different ratios. The samples of WC, PKS, and OPMF were prepared in four different ratios, namely, 88:12:0, 85:15:0, 85:13:2, and 85:10:5, for efficient biomass utilization. The 85:10:5 (WC: PKS: OPMF) ratio was found to be the optimal ratio as the annual production costs of rubber gloves significantly decreased to USD 1.64 per 1000 units of gloves. Furthermore, this biomass ratio also showed the best boiler efficiency of 74.87%. Therefore, WC, PKS, and OPMF biomass are recommended as fuel for rubber glove industries to make sustainable and economical production processes. Full article