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Poplar is an important wood bioresource and is one of the most dominant plantations in the world with high content of cellulose (52.99%). However, the pyrolytic products produced from poplar pyrolysis are not well studied and applied. In this study, pyrolysis of poplar mixed with different types and the ratio of nanometal oxide catalyst (NiO: 0.50 g, NiO–Ag: 0.25 + 0.25 g, Ag: 0.50 g, Fe2O3: 0.50 g, and Fe2O3–Ag: 0.25 + 0.25 g) were performed to identify the catalyst showing desirable performance in poplar pyrolysis. The thermogravimetry (TG) analysis revealed that adding Fe2O3 in pyrolysis has enhanced the decomposition of poplar where most of the weight loss (71.61 wt%) was in the temperature range of 25–780 °C. The results of the gas chromatography/mass spectrometry (GC/MS) analysis showed that the primary components of the produced bio-oil are acetaldehyde, methyl glyoxal, furfural, d-allose, and acetic acid, which can be used as raw materials in pharmaceuticals, industrial processes, and agricultural endeavours.

Microwave pyrolysis combined with CO2 and steam environment is investigated for its feasibility as an alternative method for waste disposal. The combined use of CO2 and steam under microwave radiation created a synergistic effect in enhancing the thermal cracking of waste material during pyrolysis. The motivation of using CO2 is to replace N2 as carrier gas during pyrolysis as an effort to reduce the production of potent greenhouse gas. In this study, different types of microwave pyrolysis are performed including conventional, CO2 and CO2+steam on waste particleboard. It was found that the utilization of steam and CO2 affect the final pyrolytic products yield and composition. Incorporating CO2 and steam in microwave pyrolysis decreased the yield of char by 33% but increased the yield of bio-oil by 108%. Biochar obtained under CO2 showed well-developed and cleaner pore structure compared to biochar produced under N2. Our results demonstrate that the utilization of CO2 and steam in microwave pyrolysis shows great potential to convert wastes into value-added char and bio-oil with desirable properties.

The valorization and conversion of biomass into various value-added products and bioenergy play an important role in the realization of sustainable circular bioeconomy and net zero carbon emission goals. To that end, microwave technology has been perceived as a promising solution to process and manage oil palm waste due to its unique and efficient heating mechanism. This review presents an in-depth analysis focusing on microwave-assisted torrefaction, gasification, pyrolysis and advanced pyrolysis of various oil palm wastes. In particular, the products from these thermochemical conversion processes are energy-dense biochar (that could be used as solid fuel, adsorbents for contaminants removal and bio-fertilizer), phenolic-rich bio-oil, and H

The global population growth continuously increases the demands for agroforestry-derived products including energy to sustain food security, transportation and industrial sectors. The high demand for the sustainable energy sources has led to an increase in the application of pesticides associated with growing crops for use in biofuel production. In this review, we focus on the interaction between pesticide use, biofuel production, food security and the balance between benefits, environmental and human health side effects, aiming to track the implications and impact to the global efforts towards achieving the UN Sustainable Development Goals (SDGs). There are national, regional and federal regulations and legislations pertaining to pesticide use, and policies devised as guidelines for agroforestry sectors to implement and monitor these measures, however, discrepancies exist between national and supranational entities. Many efforts have been made to upscale biofuel production, and policies in for example the United States, Brazil and China support the use of biofuels production from non-food-based feedstock while other developing nations are rapidly catching up. This nexus between Biofuels-Pesticides-Agroforestry (BPA) is discussed to create a sustainable roadmap toward the UN SDGs including fulfilling the energy, food, and land security. The contribution of technologies in BPA such as genetic modified crops, integrated pest and weed management with controlled release pesticides, use of biopesticides and nano-pesticides have also been reviewed. The growth of global population continuously increases the demands for agroforestry-derived products, underpinning a sustainable growth of energy matrix in the sectors of food security, transportation, and industrial is momentous. The high demand for the sustainable energy sources has led to an increase in the application of pesticides associated with growing crops for the production of biofuel. In 2019, the global consumption of pesticides was 4.2 million tonnes. Case studies on life cycle assessment (LCA) of pesticides showed that toxicity is the major severe impact of pesticide usage, contributing to human toxicity (∼70%) and freshwater eco-toxicity (>50%). This alarming situation needs a solution as conventional pesticides pose various negative impacts to human and the environment, rendering the biofuel production process unsustainable. In this review, we focus on the interaction between pesticide use, biofuel production, food security for a sustainable balancing in between government benefits, environmental, and human health, aiming to track the implications and impact to the global efforts towards achieving the UN Sustainable Development Goals (SDGs). Even though, there are strict government regulations and legislations pertaining to pesticide use, and policies devised as guidelines for agroforestry sectors to implement and monitor these measures, the discrepancies still exist in between national and supranational entities. To cater the above issue, many efforts have been made to upscale the biofuel production, for example, the United States, Brazil, China and Indonesia have ventured into biofuels production from non-food-crops based feedstock while other developing nations are rapidly catching up. In this perspective, a sustainable nexus between Biofuels-Pesticides-Agroforestry (BPA) is essential to create a sustainable roadmap toward the UN SDGs, to fulfilling the energy, food, and land security. The contribution of technologies in BPA includes genetic modified crops, integrated pest and weed management with controlled release pesticides, use of nano-biopesticides is being reviewed. As a whole, the concept of biofuel processing complex (BPC) and farmers upskilling, together with the effective implementation of efficient policies and Internet of Things (IoT) would be the key to drive the BPA nexus towards fulfilment of SDGs.

Dwindling fossil fuels and improper waste management are major challenges in the context of increasing population and industrialization, calling for new waste-to-energy sources. For instance, refuse-derived fuels can be produced from transformation of municipal solid waste, which is forecasted to reach 2.6 billion metric tonnes in 2030. Gasification is a thermal-induced chemical reaction that produces gaseous fuel such as hydrogen and syngas. Here, we review refuse-derived fuel gasification with focus on practices in various countries, recent progress in gasification, gasification modelling and economic analysis. We found that some countries that replace coal by refuse-derived fuel reduce CO2 emission by 40%, and decrease the amount municipal solid waste being sent to landfill by more than 50%. The production cost of energy via refuse-derived fuel gasification is estimated at 0.05 USD/kWh. Co-gasification by using two feedstocks appears more beneficial over conventional gasification in terms of minimum tar formation and improved process efficiency.

The growth of global population continuously increases the demands for agroforestry-derived products, underpinning a sustainable growth of energy matrix in the sectors of food security, transportation, and industrial is momentous. The high demand for the sustainable energy sources has led to an increase in the application of pesticides associated with growing crops for the production of biofuel. In 2019, the global consumption of pesticides was 4.2 million tonnes. Case studies on life cycle assessment (LCA) of pesticides showed that toxicity is the major severe impact of pesticide usage, contributing to human toxicity (∼70%) and freshwater eco-toxicity (>50%). This alarming situation needs a solution as conventional pesticides pose various negative impacts to human and the environment, rendering the biofuel production process unsustainable. In this review, we focus on the interaction between pesticide use, biofuel production, food security for a sustainable balancing in between government benefits, environmental, and human health, aiming to track the implications and impact to the global efforts towards achieving the UN Sustainable Development Goals (SDGs). Even though, there are strict government regulations and legislations pertaining to pesticide use, and policies devised as guidelines for agroforestry sectors to implement and monitor these measures, the discrepancies still exist in between national and supranational entities. To cater the above issue, many efforts have been made to upscale the biofuel production, for example, the United States, Brazil, China and Indonesia have ventured into biofuels production from non-food-crops based feedstock while other developing nations are rapidly catching up. In this perspective, a sustainable nexus between Biofuels-Pesticides-Agroforestry (BPA) is essential to create a sustainable roadmap toward the UN SDGs, to fulfilling the energy, food, and land security. The contribution of technologies in BPA includes genetic modified crops, integrated pest and weed management with controlled release pesticides, use of nano-biopesticides is being reviewed. As a whole, the concept of biofuel processing complex (BPC) and farmers upskilling, together with the effective implementation of efficient policies and Internet of Things (IoT) would be the key to drive the BPA nexus towards fulfilment of SDGs.

Oxidation of o-xylene was performed using alkaline battery-based catalyst doped with platinum to investigate the properties and activities. O-xylene was selected as the model of volatile organic compound (VOC) in this work. Physicochemical properties of the selected catalysts were characterized by FE/TEM (field emission transmission electron microscopy), BET (Brunauer-Emmett-Teller) analysis, XRD (X-ray powder diffraction), SEM/EDX (scanning electron microscopy/energy dispersive X-ray spectroscopy), and H2-TPR (hydrogen temperature programmed reduction). Major elements of the spent alkaline battery-based catalyst treated with sulfuric acid solution [SAB (400) catalyst] were manganese, zinc, iron, oxygen, carbon, chlorine, aluminum, sodium, silicon, and potassium. Increasing the doping amount of platinum on SAB (400) catalyst from 0.1 to 1 wt% increased particle size of platinum and lowered the temperature of TPR (TTP) for SAB (400) catalyst. Better redox properties were achieved with an increase in the o-xylene conversion according to the doping amount of platinum. When GHSV (gas hourly space velocity) was 40,000 h-1, o-xylene was oxidized completely over SAB (400) catalyst and 1.0 wt% Pt/SAB(400) catalyst at temperatures of 400 °C and 280 °C, respectively.

Waste palm shell is a large-volume biomass waste produced from palm oil mills, representing a resource to be treated and converted into a value-added product. In this study, an improved microwave wet torrefaction (low-temperature pyrolysis) incorporating microwave radiation and steam was performed to torrefied the waste palm shell into higher porous biochar. The biochar and catalytic effect of using microwave radiation and steam over a range of process temperature (250–350 °C) were investigated. The microwave wet torrefaction demonstrated a significantly faster heating rate (up to 120 °C/min) and compared to that shown by microwave heating without steam (45 °C/min, 15 min). Microwave wet torrefaction exhibited relatively lower mass yield (63.5 wt%) compared to microwave torrefaction (72.5 wt%). However, the biochar obtained from microwave wet torrefaction produced higher surface area (308.0 m2/g) compared to microwave torrefaction (110.8 m2/g). Our results demonstrate that microwave wet torrefaction shows potential as a catalytic approach to treat waste palm shell in providing a fast heating rate, lower process temperature, and generating a higher yield of a torrefied product with improved properties.

Cassava stem waste is abundantly available after starch extraction, hence posing disposal problem and potential risk to environmental pollution. Alternative ways are needed to dispose the waste instead of landfilling and open burning. Microwave vacuum pyrolysis was examined as an alternative method to convert the cassava stem waste into biochar. The cassava stem was first characterized by several analyses followed by conversion into biochar using microwave vacuum pyrolysis over different microwave power. The cassava stem contained high contents of carbon (49.5 wt%) and considerable amount of fixed carbon (27 wt%), indicating its suitability to be used as pyrolysis feedstock. The biochar yield from microwave power of 550 W, 650 W and 750 W were 77%, 73% and 70% respectively. The surface morphology of biochar shows that it consists abundant pores on the surface, suggesting its suitability to be used as catalyst support for energy application, and also as adsorbent for use in adsorption-related process such as dye and heavy metal removal in wastewater treatment or nutrient retention in crops cultivation. The calorific value of the biochar ranged from 19.24 to 20.55 MJ kg−1, showing high energy content for potential use as solid fuel. Our results show that cassava stem can be transformed into biochar for useful energy applications rather than burned as low-grade fuel in boiler or disposed by landfilling.

Thermal co-processing of lignocellulosic and aquatic biomass, such as algae and shellfish waste, has shown synergistic effects in producing value-added energy products with higher process efficiency than the traditional method, highlighting the importance of scaling up to pilot-scale operations. This article discusses the design and operation of pilot-scale reactors for torrefaction, pyrolysis, and gasification, as well as the key parameters of co-processing biomass into targeted and improved quality products for use as fuel, agricultural application, and environmental remediation. Techno-economic analysis reveals that end product selling price, market dynamics, government policies, and biomass cost are crucial factors influencing the sustainability of thermal co-processing as a feasible approach to utilize the biomass. Because of its simplicity, pyrolysis allows greater energy recovery, while gasification has the highest net present value (profitability). Integration of liquefaction, hydrothermal, and fermentation pre-treatment technology has the potential to increase energy efficiency while reducing process residues.

Blockchain-integrated waste management and circular economy are emergent concepts that target minimising waste generation and fluctuations of resource commodity. Blockchain can support a circular economy and green principles by enabling information transparency, reliability and automation. Redesigning plastics by molecular tagging is the way forward to ensure synthetic plastics are kept in an infinite loop and support closed-loop recycling. The involvement of major corporations in product development and blockchain-integrated closed-loop recycling has resulted in several successful green chemical approaches toward circular plastic economy projects. Government policies and legislations are progressively supporting plastic redesigning for improving the plastic circular economy. Nevertheless, a systematic approach is required in addressing blockchain technology and plastic redesigning to effectively leverage circular economy initiatives.

Waste furniture boards (WFBs) contain hazardous formaldehyde and volatile organic compounds when left unmanaged or improperly disposed through landfilling and open burning. In this study, pyrolysis was examined as a disposal and recovery approach to convert three types of WFBs (i.e., particleboard, plywood, and fiberboard) into value-added chemicals using thermogravimetric analysis coupled with Fourier-transform infrared spectrometry (TG-FTIR) and pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS). TG-FTIR analysis shows that pyrolysis performed at an optimum temperature of 250–550 °C produced volatile products mainly consisting of carbon dioxide, carbon monoxide, and light hydrocarbons, such as methane. Py-GC/MS shows that pyrolysis at different final temperatures and heating rates recovered mainly phenols (25.9–54.7%) for potential use as additives in gasoline, colorants, and food. The calorific value of WFBs ranged from 16 to 18 MJ/kg but the WFBs showed high H/C (1.7–1.8) and O/C (0.8–1.0) ratios that provide low chemical energy during combustion. This result indicates that WFBs are not recommended to be burned directly as fuel, however, they can be pyrolyzed and converted into solid pyrolytic products such as biochar with improved properties for fuel application. Hazardous components, such as cyclopropylmethanol, were removed and converted into value-added compounds, such as 1,4:3,6-dianhydro- d -glucopyranose, for use in pharmaceuticals. These results show that the pyrolysis of WFBs at high temperature and low heating rate is a promising feature to produce value-added chemicals and reduce the formation of harmful chemical species. Thus, the release of hazardous formaldehyde and greenhouse gases into the environment is redirected.

We analyzed the problematic textile fiber waste as potential precursor material to produce multilayer cotton fiber biocomposite. The properties of the products were better than the current dry bearing type particleboards and ordinary dry medium-density fiberboard in terms of the static bending strength (67.86 MPa), internal bonding strength (1.52 MPa) and water expansion rate (9.57%). The three-layer, four-layer and five-layer waste cotton fiber composite (WCFC) were tried in the experiment, the mechanical properties of the three-layer WCFC are insufficient, the five-layer WCFC is too thick and the four-layer WCFC had the best comprehensive performance. The cross-section morphology of the four-layer WCFC shows a dense structure with a high number of adhesives attached to the fiber. The hardness and stiffness of the four-layer cotton fiber composite enhanced by the high crystallinity of cellulose content, and several chemical bondings were presence in the composites. Minimum mass loss (30%) and thermal weight loss rate (0.70%/°C) was found for the four-layer WCFC. Overall, our findings suggested that the use of waste cotton fiber (WCF) to prepare biocomposite with desirable physical and chemical properties is feasible, and which can potentially be used as building material, furniture and automotive applications.

Pyrolysis is a potential technology used for the transformation of municipal wastes into energy products such as biofuel. Existing reviews on pyrolysis mainly focus on agroforestry biomass and conventional pyrolysis heating techniques. There is limited literature on the application of recent pyrolysis techniques, types of reactors, key operating parameters, and properties of pyrolysis products from conventional versus recent/novel pyrolysis techniques, and particularly the application of the oil products in fuel engines. Here we focus on the performance of various pyrolysis techniques for valorizing municipal wastes, with an explicit emphasis on the progress and application of co-pyrolysis as a recent technique for value-added products recovery from municipal wastes. We review the main operating parameters of co-pyrolysis, concerns and disputes arisen from the technique, and the resultant liquid fuel properties. In particular, co-pyrolysis using microwave heating shows proficiency to resolve several drawbacks of conventional pyrolysis techniques such as reduced oxygen content and viscosity and increased calorific value of liquid oil, hence promising as a method to generate environmental friendly and sustainable third-generation fuels. Sorting of municipal wastes is recommended as an approach to improve the feasibility of co-pyrolysis by having desired quantity and type of municipal wastes as the feedstock, and more research and development on co-pyrolysis utilizing municipal wastes is necessary to maximize the yield and quality of target pyrolytic products. Thus, we conclude that co-pyrolysis is a feasible and sustainable method for recovering biofuel from municipal wastes to obtain green energy and energy security.

The valorization of biochar as a green and low-cost adsorbent provides a sustainable alternative to commercial wastewater treatment technologies that are usually chemical intensive and expensive. This review presents an in-depth analysis focusing on the rice straw-derived biochar (RSB) for removal of various types of contaminants in wastewater remediation. Pyrolysis is to date the most established technology to produce biochar. Subsequently, biochar is upgraded via physical, chemical or hybrid activation/modification techniques to enhance its adsorption capacity and robustness. Thus far, acid-modified RSB is able to remove metal ions and organic compounds, while magnetic biochar and electrochemical deposition have emerged as potential biochar modification techniques. Besides, temperature and pH are the two main parameters that affect the efficiency of contaminants removal by RSB. Lastly, the limitations of RSB in wastewater remediation are elucidated based on the current advancements of the field, and future research directions are proposed.

Global warming is reducing the Arctic sea-ice and causing energetic stress to marine key predatory species such as polar bears and narwhals contributing to the ongoing pollution already threatening the biodiversity and indigenous people of the vulnerable region. Now, the opening of the Arctic gateway and in particular the increase in shipping activities causes further stress to marine mammals in the region. These shipping activities are foreseen to happen in the Northwest and Northeast Passage, Northern Sea Route and Transpolar Sea Route in the Arctic Ocean, which could be yet another step towards a crucial tipping point destabilizing global climate, including weathering systems and sea-level rise. This calls for international governance through the establishment of Arctic International National Parks and more Marine Protected Areas through the Arctic Council and UN's Law of the Sea to ensure sustainable use of the Arctic Ocean and adjacent waters. Global warming is reducing the Arctic sea-ice and causing energetic stress to marine key predatory species such as polar bears and narwhals contributing to the ongoing pollution already threatening the biodiversity and indigenous people of the vulnerable region. Now, the opening of the Arctic gateway and in particular the increase in shipping activities causes further stress to marine mammals in the region. These shipping activities are foreseen to happen in the Northwest and Northeast Passage, Northern Sea Route and Transpolar Sea Route in the Arctic Ocean, which could be yet another step towards a crucial tipping point destabilizing global climate, including weathering systems and sea-level rise. This calls for international governance through the establishment of Arctic International National Parks and more Marine Protected Areas through the Arctic Council and UN's Law of the Sea to ensure sustainable use of the Arctic Ocean and adjacent waters.

Hydrogen and gaseous fuel derived from wastes have opened up promising alternative pathways for the production of renewable and sustainable fuels to substitute classical fossil energy resources that cause global warming and pollution. Existing review articles focus mostly on gasification, reforming and pyrolysis processes, with limited information on particularly gaseous fuel production via pyrolysis of various waste products. This review provides an overview on the recent advanced pyrolysis technology used in hydrogen and gaseous fuel production. The key parameters to maximize the production of specific compounds were discussed. More studies are needed to optimize the process parameters and improve the understanding of reaction mechanisms and co-relationship between these advanced techniques. These advanced techniques provide novel environmentally sustainable and commercially procedures for waste-based production of hydrogen and gaseous fuels.

Co-pyrolysis has been researched as a promising technique for thermochemical conversion of biomass with plastics and other organic wastes into potentially useful products due to the ability to recover energy from these materials. This chapter presents a review of the development and application of co-pyrolysis as a next-generation thermochemical conversion technique for energy recovery from biomass waste materials (e.g., food waste, waste cooking oil etc.). This includes a discussion on the characteristics of co-pyrolysis, the key process parameters, the issues, and challenges arising from the application of co-pyrolysis, and the features and combustion performance of the liquid oil product. Co-pyrolysis using microwave technique shows ability to rectify certain limitations shown by conventional pyrolysis with a potential as a viable means to produce next-generation fuels from biomass wastes. This co-pyrolysis approach is capable of increasing the yield and enhancing the quality of the bio-oil product. Thus, it can be a potentially sustainable and feasible approach for energy recovery from biomass and wastes polymers.

Structural health monitoring (SHM) plays a significant role to avoid the catastrophic failure of composites during practical applications. This research developed a polyacrylonitrile and flexible barium titanate (PAN/BaTiO3) piezoelectric nanofiber membranes sensor for real-time damage detection in composites. The conversion between mechanical energy and electrical energy of the sensor was verified by an electrochemical system. The introduction of BaTiO3 nanoparticles improved the mechanical-to-electrical output of 9.3 V of peak values with 15 wt% loaded piezoelectric nanofiber membranes. In the application test, slight deformation on the piezoelectric nanofiber membranes sensor instantly lighted up the commercial LED bulbs. Moreover, the piezoelectric PAN/BaTiO3 sensor still created piezoelectric effect within the composite after curing with carbon fiber, and improved the interlaminated shear strength. The bending and piezoelectric properties of the composite were tested simultaneously. The composite showed good response to electrical signals during the mechanical loading and achieving real-time monitoring of the delamination failure. This sensor showed good potential as a flexible reinforcement in composite materials for SHM applications.

Utilization of lignocellulosic biomass is increasingly important. Jasminum nudiflorum Lindl. (JNL) is a widely cultivated landscape plant in China. To evaluate the chemical components, pyrolysis characteristics as well as the potential values of JNL bark for utilization, the components were extracted using methanol, ethanol, and benzene/ethanol (2:1, v/v) and pyrolyzed from room temperature to 300 °C, respectively. Many components were detected in the extracts and the pyrolyzates of JNL bark and their chemical properties were analyzed. The compounds identified in the extracts and the pyrolyzates of JNL bark included acids, aldehydes, alcohols, esters, ketones, aromatics, saccharides, olefins, and nitrogen-containing compounds. Some of the identified compounds, such as urs-12-en-28-al, 3-(acetyloxy)-, (3.beta.)-, 5-hydroxymethylfurfural, and vanillin, are widely used in the medical, energy, and food industries. The pyrolysis of JNL bark using thermogravimetric (TG) analyzer showed the highest reaction rate occurred at between 200 and 300 °C where the maximum mass loss was observed. According to the Coats-Redfern method, the calculated apparent activation energy (E) and pre-exponential factor (A) of the pyrolysis process of JNL bark were 52.04 kJ mol−1 and 3.14 × 105 min−1, respectively. This research provides information on the components and pyrolysis characteristics of JNL bark, which shows great potential for application in medical, food, and chemical industries.

Poly (lactic acid) (PLA) has been widely used in preparation of biomass composites in recent years. Ramie fiber (RFs) can be introduced as a reinforcing element to enhance the performance of PLA composites. In this study, a novel fabrication technology through the combination of two-dimensional (2D) braiding and three-dimensional (3D) weaving are used for the preparation of RF/PLA composites with optimized mechanical properties. The twist ratio of ply/single yarn, the curing parameters, and RF content are considered to optimize the mechanical properties of the 3D orthogonal woven composites (3D composites). The tensile strength of RF ply yarn composites increases firstly and then decreases with the increase of twist ratio, and reach the maximum tensile strength (60.4 MPa) when the twist ratio is 0.3. The flexural and shearing properties of the 3D RF/PLA composites reach maximum under optimal curing conditions (190 ℃, 5 MPa, 30 min) at 50% RF content. The maximum flexural strength and modulus are higher than those reported for short RF composites and RF fabric composites. The high performance and low-cost 3D RF/PLA composites have good application potential in the automobile manufacturing industry.

Pollution with pesticides is a widespread global problem and biomonitoring of the environment and human populations is necessary to assess potential harmful biological effects. One of the pesticides that are showing up in vegetables and fruit is chlorpyrifos (CPS). CPS is a nerve-poisoning organophosphorus insecticide, which is in up to 1/3 of all conventionally produced citrus fruits. Our review shows that CPS is a hazardous material that poses risks to human health and also pollutes the environment. There is numerous risk assessment of CPS reported, however, the assessment is easily affected by factors such as climate change, exposure period and CPS concentration. Therefore, rigorous update of the hazardous level of CPS is needed to determine the threshold level safe for humans and animals. There is a need for remediation using for example photoreactive nanoparticle methods and microbial degeneration possessing high degradation efficiency (73-97%). In addition, stringent biomonitoring of food, environment and human exposure should occur to avoid exposure to chemicals via citrus fruits and vegetables. This is necessary to assess health risks and socioeconomic impacts which also require collaboration between private and public sectors to facilitate the growth, sale and manufacturing of biopesticides.

The escalating consumption of fossil fuels and dumping of palm kernel shells (PKS) drives biofuel production to improve supply and waste disposal. To convert PKS into modified biochar (MBC) value-added solid fuel, we use microwave vacuum pyrolysis accompanied by sodium-potassium hydroxide mixture modification. First, PKS underwent microwave vacuum pyrolysis to produce biochar, and then it was chemically activated using sodium-potassium hydroxide mixture. The MBC surface morphology, porous characteristics, proximate content, and energy properties depended on microwave irradiation period and power. High yields (79 ± 1.5 wt%) were recorded at microwave power 700 W and irradiation period of 10 min, giving a high BET surface area (1320 m2/g) and pore volume (0.70 cm3/g). The MBC had acceptable low content of ash, nitrogen, and no sulphur, demonstrating its potential as an environmental friendly fuel to replace conventional coal in combustion. The MBC shows high energy yield (≤90.5%), fuel ratio (≤26.47), and heating value (≤28.69 MJ/kg) comparable to conventional fuels, thus showing desirable solid fuel properties. Energy balance analysis shows positive energy ratio of up to 10 and net energy output of up to 24.47 MJ/kg, recovering a product with a higher energy content compared to electrical power input for the pyrolysis operation. These findings demonstrate the exceptional potential of the MBC produced by this innovative approach for bioenergy generation that per se will reduce the emissions of greenhouse gases and thereby reducing global warming and climate change.