Numerical simulation and experimental validation of microwave torrefaction for empty fruit bunches pellet

This study investigates the microwave heating and torrefaction process of empty fruit bunch (EFB) pellets. Finite element based COMSOL Multiphysics software was used to predict the microwave heating behaviour of EFB pellets during the torrefaction process. The simulated temperature data from multimode microwave system at 2.45 GHz frequency was used to compare and validate the experimental results. Quantitative validation of 10 min temperature profiles between 25-300 °C was performed by comparing the simulated and experimental results. RMSE and maximum different temperature profile were 16.42 and 38°C respectively which may cause by the moisture of pellet, exothermic reaction and placement of the thermocouple during microwave torrefaction process. The simulation work has successfully identified the hot spots of EFB pellets during microwave torrefaction. Hot spot happened in the temperature range of 250-450 °C and was observed near the waveguide and centre of the EFB pellets bed. This study provided a framework and required model parameters to predict temperature profile and hot spot location for a specific geometry of microwave cavity

Oil palm waste: An abundant and promising feedstock for microwave pyrolysis conversion into good quality biochar with potential multi-applications

Oil palm waste (OPW), comprising mainly of empty fruit bunch, mesocarp fiber, frond, trunk, and palm kernel shell generated from palm oil industry, was collected, characterized, and then pyrolyzed to evaluate their potential to be converted into biochar with desirable properties for use in multi-applications. The OPW was detected to have considerable amounts of carbon (43–51 wt%) and fixed carbon (30–39 wt%), showing potential to be converted into carbon-rich biochar. Microwave pyrolysis of palm kernel shell as the selected OPW produced a biochar with zero sulphur content and high heating value (23–26 MJ/kg) that is nearly comparable to conventional coal, thus indicating its potential as an eco-friendly solid fuel. The biochar obtained was also showed low moisture (<3 wt%) and ash (3 wt%), and a highly porous structure with high BET surface area (210 m2/g), indicating the presence of many adsorption sites and thus showing desirable characteristics for potential use as pollutant adsorbent in wastewater treatment, or bio-fertilizer to absorb nutrient and promote plant growth. Our results demonstrate that OPW is a biowaste that shows exceptional promise to be transformed into high-grade biochar rather than simply disposed by landfilling or burned as low-grade fuel in boiler

Recent progress in the production and application of biochar and its composite in environmental biodegradation

Over the past few decades, extensive research has been conducted to develop cost-effective and high-quality biochar for environmental biodegradation purposes. Pyrolysis has emerged as a promising method for recovering biochar from biomass and waste materials. This study provides an overview of the current state-of-the-art biochar production technology, including the advancements and biochar applications in organic pollutants remediation, particularly wastewater treatment. Substantial progress has been made in biochar production through advanced thermochemical technologies. Moreover, the review underscores the importance of understanding the kinetics of pollutant degradation using biochar to maximize its synergies for potential environmental biodegradation. Finally, the study identifies the technological gaps and outlines future research advancements in biochar production and its applications for environmental biodegradation

Biowastes as sustainable source for nanoparticle synthesis and their pesticide properties: A review

Over the last decade, nanoparticles derived from biowaste have been widely investigated as one of the greener approaches to preparing pesticides as its application offer the usage of environmentally friendly and earth-abundance resources, cost effectiveness due to low energy consumption, biocompatibility, as well as flexibility in preparation of biomolecules as a medium or bio-reducing agents for pesticide production. Integrating biowastes in nanomaterials-based pesticide preparation marks a new age of innovation in nanomaterial technology to overcome the contemporary problems currently plaguing the agriculture sector with the possibility of mitigating environmental pollution. In this review, the synthesis of nanomaterials derived from biowastes as agrochemicals and their advantages are presented. It is expected that this review would serve as a guide for selected industry and scientific communities working with nanomaterials in the form of agrochemicals to enhance crop protection. It is anticipated that the next generation agrochemicals will mark the use of ecofriendly sustainable materials to which nanomaterials-based pesticides derived from the biowastes will play a major part ensuring food security thus achieving the Zero Hunger goal in the Sustainable Development Goals

Activated Carbon for Catalyst Support from Microwave Pyrolysis of Orange Peel

Orange peel, representing an abundant fruit waste in Asia, was transformed into activated carbon via the use of microwave pyrolysis. The orange peel was first subjected to microwave pyrolysis over a range of microwave power in order to produce an optimal yield of activated carbon as the target product. The activated carbon was extensively characterized for its porous characteristics, N2 adsorption and desorption isotherms, thermal stability, and chemical composition in order to assess its potential to be used as a catalyst-support material. Microwave pyrolysis of orange peel showed an approximately 70 wt% yield of activated carbon over the range of microwave power considered. The activated carbon was detected to have a high BET surface area associated with type I isotherm, which indicates the presence of microporous structure, thus exhibiting a characteristic of high adsorption capacity. The high adsorption capacity suggests that the activated carbon produced using this pyrolysis approach could act as an adsorbent to adsorb metal ions, therefore it shows great potential to be used as a catalyst-support material—the base material to which catalytically active substance such as metal binds to form a heterogeneous catalyst. The activated carbon also demonstrated high thermal stability in N2 atmospheres, representing a durable material to be synthesized into a catalyst for use in thermal process. Our results show that the activated carbon produced from microwave pyrolysis of orange peel shows exceptional promise as a catalyst-support material

Microwave pyrolysis using self-generated pyrolysis gas as activating agent: An innovative single-step approach to convert waste palm shell into activated carbon

Waste palm shell (WPS) is a biomass residue largely available from palm oil industries. An innovative microwave pyrolysis method was developed to produce biochar from WPS while the pyrolysis gas generated as another product is simultaneously used as activating agent to transform the biochar into waste palm shell activated carbon (WPSAC), thus allowing carbonization and activation to be performed simultaneously in a single-step approach. The pyrolysis method was investigated over a range of process temperature and feedstock amount with emphasis on the yield and composition of the WPSAC obtained. The WPSAC was tested as dye adsorbent in removing methylene blue. This pyrolysis approach provided a fast heating rate (37.5°/min) and short process time (20 min) in transforming WPS into WPSAC, recording a product yield of 40 wt%. The WPSAC was detected with high BET surface area (≥ 1200 m2/g), low ash content (< 5 wt%), and high pore volume (≥ 0.54 cm3/g), thus recording high adsorption efficiency of 440 mg of dye/g. The desirable process features (fast heating rate, short process time) and the recovery of WPSAC suggest the exceptional promise of the single-step microwave pyrolysis approach to produce high-grade WPSAC from WPS

Microwave pyrolysis using self-generated pyrolysis gas as activating agent: An innovative single-step approach to convert waste palm shell into activated carbon

Waste palm shell (WPS) is a biomass residue largely available from palm oil industries. An innovative microwave pyrolysis method was developed to produce biochar from WPS while the pyrolysis gas generated as another product is simultaneously used as activating agent to transform the biochar into waste palm shell activated carbon (WPSAC), thus allowing carbonization and activation to be performed simultaneously in a single-step approach. The pyrolysis method was investigated over a range of process temperature and feedstock amount with emphasis on the yield and composition of the WPSAC obtained. The WPSAC was tested as dye adsorbent in removing methylene blue. This pyrolysis approach provided a fast heating rate (37.5°/min) and short process time (20 min) in transforming WPS into WPSAC, recording a product yield of 40 wt%. The WPSAC was detected with high BET surface area (≥ 1200 m2/g), low ash content (< 5 wt%), and high pore volume (≥ 0.54 cm3/g), thus recording high adsorption efficiency of 440 mg of dye/g. The desirable process features (fast heating rate, short process time) and the recovery of WPSAC suggest the exceptional promise of the single-step microwave pyrolysis approach to produce high-grade WPSAC from WPS

Production of bio-fertilizer from microwave vacuum pyrolysis of waste palm shell for cultivation of oyster mushroom (Pleurotus ostreatus)

Microwave vacuum pyrolysis of waste palm shell (WPS) was performed to produce biochar, which was then tested as bio-fertilizer in growing Oyster mushroom (Pleurotus ostreatus). The pyrolysis approach generated a biochar containing a highly porous structure with a high BET surface area (up to 1250 m2/g) and a low moisture content (≤ 10 wt%), exhibiting desirable adsorption properties to be used as bio-fertilizer since it can act as a housing that provides many sites on which living microorganisms (mycelium or plant-growth promoting bacteria) and organic nutrients can be attached or adsorbed onto. This could in turn stimulate plant growth by increasing the availability and supply of nutrients to the targeted host plant. The results from growing Oyster mushroom using the biochar record an impressive growth rate and a monthly production of up to about 550 g of mushroom. The shorter time for mycelium growth on whole baglog (30 days) and the highest yield of Oyster mushroom (550 g) was obtained from the cultivation medium added with 20 g of biochar. Our results demonstrate that the biochar-based bio-fertilizer produce from microwave vacuum pyrolysis of WPS show exceptional promise as an alternative growing substrate for mushroom cultivation

Converting food waste to biofuel: A sustainable energy solution for Sub-Saharan Africa

Natural gas, coal, and oil account for over 84 % of the world’s energy demand. Greenhouse gases, including carbon dioxide, methane, and oxides of nitrogen and sulphur, are released during the combustion of fossil fuels, leading to substantial climate changes and environmental damage. Therefore, harnessing energy from alternative sustainable resources without the emission of harmful waste products is vital for the ecosystem’s health. By 2050, global food waste production will reach 3.4 billion metric tons. Although widely recognized as a substantial energy resource, its value is underutilized throughout sub-Saharan Africa (SSA). Therefore, understanding and exploiting the potential value of food waste as a biofuel can result in net-zero emissions, reducing significant environmental pollution while conserving natural resources. Furthermore, this paper reviews how effective management of food waste will have the potential to contribute to the development of waste-to-energy resources in SSA countries, as well as help improve global ecosystems

Production of bio-fertilizer from microwave vacuum pyrolysis of waste palm shell for cultivation of oyster mushroom (

Microwave vacuum pyrolysis of waste palm shell (WPS) was performed to produce biochar, which was then tested as bio-fertilizer in growing Oyster mushroom (Pleurotus ostreatus). The pyrolysis approach generated a biochar containing a highly porous structure with a high BET surface area (up to 1250 m2/g) and a low moisture content (≤ 10 wt%), exhibiting desirable adsorption properties to be used as bio-fertilizer since it can act as a housing that provides many sites on which living microorganisms (mycelium or plant-growth promoting bacteria) and organic nutrients can be attached or adsorbed onto. This could in turn stimulate plant growth by increasing the availability and supply of nutrients to the targeted host plant. The results from growing Oyster mushroom using the biochar record an impressive growth rate and a monthly production of up to about 550 g of mushroom. The shorter time for mycelium growth on whole baglog (30 days) and the highest yield of Oyster mushroom (550 g) was obtained from the cultivation medium added with 20 g of biochar. Our results demonstrate that the biochar-based bio-fertilizer produce from microwave vacuum pyrolysis of WPS show exceptional promise as an alternative growing substrate for mushroom cultivation