Top-lit Updraft Research Articles

Gasification of sago dreg waste in a top-lit updraft fixed bed gasifier: Syngas composition and its effect with additional Al2O3 as catalyst

Sago-based foods have become a staple food in eastern Indonesia. Sago waste, as a by-product, has the potential to be used as a renewable energy fuel. This research aims to use sago dregs waste as an energy source by converting it into renewable energy using Top Lit Updraft (TULD) fixed bed gasification. Al2O3, a potential solid waste derived from coal fly ash, is also being investigated for use in sago dreg pellets.The two various Al2O3 contents in sago dreg pellets that will be examined with 5 % Al2O3 and 10 % Al2O3. Operational parameters employed in the gasification process involving the TULD reactor, such as gasification temperature, air flow rate, air-to-fuel ratio (AFR), and syngas assessment. According to the results, adding Al2O3 as a catalyst to sago dreg pellets can improve syngas production (H2, CO, and CH4). The most significant alteration is that the average hydrogen gas (H2) content has increased, with the greatest being in 5 % Al2O3 with 31.65 %, and 10 % Al2O3 with 29.94 %. Meanwhile, the CO and CH4 gas content was found to be highest at 10 % Al2O3, with each experiencing an increase in average (CO 4.33 % and CH4 26.45 %) as compared to sago dregs pellets without Al2O3. Finally, sago dregs pellets with an Al2O3 catalyst have a high potential as an alternative energy fuel for internal combustion engines with H2/CO of 1.65 and 1.51 respectively, for 5 % Al2O3 and 10 % Al2O3, with low tar content.

Impact of carbonization reactor compartment size on groundnut (Arachis hypogaea) shell biochar properties

Abstract This study investigates the impact of low-temperature top-lit updraft reactor chamber size on GNSBC yield and properties. For this study, the volumes of carbonization chamber (2,364, 2,013, 1,468, and 970 cm3) in a biomass-fueled TLUD biomass gasifier were varied, and the resulting biochar was analyzed using SEM, EDX, and FTIR. The novelty of this work lies in its investigation of the unexplored impact of carbonization reactor compartment size on groundnut shell biochar properties and yield, driven by the need to optimize biochar production efficiency and support sustainable waste management practices. The results showed that carbonization chamber size variation significantly affected GNSBC yield, with an initial increase followed by diminishing returns. An increase in the carbonization compartment size led to decreased carbonization duration, increased carbonization temperature, increased porosity, and decreased oxygen content. SEM analysis revealed consistent amorphous and multi-layered morphological features across BC samples, while EDX analysis confirmed high carbon content in the samples. FTIR spectroscopy confirmed the presence of oxygenated functional groups suitable for pollutant adsorption, supporting GNSBC’s role in environmental remediation and industrial processes. This research contributes to optimizing biochar production efficiency, advancing circular economy goals, and sustainable waste management practices.

Teak leaf biochar production for sustainable forest waste management at low temperatures

This study investigates the possibilities of producing biochar from teak leaves as an environmentally beneficial approach to managing forest waste in a sustainable manner. Teak leaves, a readily available forest by-product, were converted into biochar through a low-temperature pyrolysis process using a top-lit updraft mechanism. The results demonstrate the efficiency of this approach, yielding a substantial biochar output of 37.4 wt%, with its thermal field modelled perfectly via Levenberg-Marquardt algorithm in ANN topology. Elemental analysis of the teak leaf biochar revealed a high carbon content of 64.40%, positioning it as a valuable carbon-rich material suitable for various applications. Textural properties analysis indicated a significant surface area of 371.78 m2/g and a total pore volume of 0.175 cm³/g, enhancing its potential for various applications. Scanning Electron Microscopy (SEM) investigations showed a diverse network of pores and a rough surface structure, reinforcing the biochar’s versatility. This study shows the environmental benefits of low-temperature teak leaf biochar production, because it provides a carbon-content-preserving, sustainable alternative for handling forest wastes.

Fuelwood use and household appreciation of improved and traditional cooking stoves in Rwanda

More than 90 % of the rural population in Rwanda (72 % of the total population) utilizes the inefficient traditional three-stone fireplaces (TSF), and 65 % of the urban population uses charcoal for cooking. Firewood is bulky and heavy to transport and store in urban areas, and charcoal stoves are more efficient and less smoky than TSF. However, most energy and wood are lost when converting firewood to charcoal. Traditional charcoal kiln often has an average of 12 % conversion efficiencies in Rwanda. Several improved cooking stoves (ICS) have been developed as alternatives to the TSF and charcoal stoves, but their efficiencies and household appreciation in real-life conditions are poorly understood. This study assesses the fuelwood use efficiency of two ICSs, MimiMoto and Kuniokoa stoves. The Kuniokoa is a rocket stove that uses firewood, while the MimiMoto is a top-lit-up-draft (TLUD) gasification stove fuelled with wood pellets. The MimiMoto stoves were delivered to 15 selected households using charcoal stoves, while the Kuniokoa stoves were given to 30 households using TSF. The amount of wood consumed and time spent during cooking were recorded for a standardized traditional dish. The Kuniokoa stove consumed 0.9kg/cooking session, while the TSF consumed 1.6 kg/cooking session. Switching from TSF to Kuniokoa stoves in rural areas reduces fuelwood consumption by 41 %. MimiMoto and charcoal stoves consume 0.50 and 0.48 kg/cooking session. However, 0.48 kg charcoal is equivalent to 4 kg firewood; hence, switching from charcoal stoves to MimiMoto stoves results in a firewood reduction of 88 %. Analysis of cooking times shows small differences between TSF, Kuniokoa, and MimiMoto, around 55–60 min, while cooking on charcoal takes significantly more time. The ICSs were highly appreciated by participating households, especially for their fuel saving, ease of use, reduced smokiness, and general cleanliness. Based on the results, it can be concluded that efficient rocket stoves, like Kuniokoa, are viable alternatives to TSF for household cooking in rural areas and that efficient TLUD stoves, like the MimiMoto, are good alternatives to replace charcoal stoves in urban and peri-urban areas. Aggregated to annual and national scales, such changes would have substantial positive implications for the environment and livelihoods.

Multi-Criteria Optimization of a Laboratory Top-Lit Updraft Gasifier in Order to Reduce Greenhouse Gases and Particulate Matter Emissions

Air pollution from combustion processes is harming human health and the environment. To mitigate this, one needs to adopt cleaner energy production methods, in particular, to optimize combustion systems in order to minimize pollutants and increase efficiency. Flue gas analysis and particulate matter (PM) monitoring, starting from the prototype phase, is crucial to minimize and regulate pollutant emissions. This article analyses the emissions of pollutants and particulate matter from a combustion test gasifier working on the Top-Lit Updraft (TLUD) principle in order to optimize functionality and reduce exhaust emissions. Three experiments were performed in which the primary (gasification) air flow rate (GA) was kept constant at 25 L/min, and the secondary (combustion) air flow rate (CA) was adjusted to obtain a CA/GA ratio of 2 (50 L/min), 3 (75 L/min), and 4 (100 L/min) respectively. Based on a multi-criterial analysis, the optimal CA/GA ratio for TLUD combustion is 3, offering a well-rounded performance in output temperatures, PM and greenhouse gases (GHG) emissions, and efficiency, while the CA/GA ratio of 4 has good PM and GHG emissions performance but lower efficiency, and the CA/GA ratio of 2 is the least favorable due to its poor performance in output temperatures, PM and GHG emissions.

Emission of volatile organic compounds during open fire cooking with wood biomass: Traditional three-stone open fire vs. gasifier cooking stove in rural Kenya

Cooking with wood biomass fuels releases hazardous air pollutants, including volatile organic compounds (VOCs), that often disproportionally affect women and children. This study, conducted in Kwale and Siaya counties in Kenya, employed thermal desorption gas chromatography – mass spectrometry to analyse VOC emissions from cooking with a wood biomass three-stone open fire vs. top-lit updraft gasifier stove. In kitchens with adequate ventilation, total VOC levels increased from 35–252 μg∙m−3 before cooking to 2235–5371 μg∙m−3 during open fire cooking, whereas use of a gasifier stove resulted in reduced emissions from cooking by 48–77 % (506–2778 μg∙m−3). However, in kitchens with poor ventilation, there was only a moderate difference in total VOC levels between the two methods of cooking (9034–9378 μg∙m−3 vs. 6727–8201 μg∙m−3 for the three-stone open fire vs. gasifier stove, respectively). Using a non-target screening approach revealed significantly increased levels of VOCs, particularly benzenoids, oxygenated and heterocyclic compounds, when cooking with the traditional open fire, especially in closed kitchens, highlighting the effects of poor ventilation. Key hazardous VOCs included benzene, naphthalene, phenols and furans, suggesting potential health risks from cooking. In kitchens with good ventilation, use of the gasifier stove markedly reduced emissions of these priority toxic VOCs compared to cooking with an open fire. Thus, substituting open fires with gasifier stoves could help to improve household air quality and alleviate health risks. The study revealed that VOCs were present prior to cooking, possibly originating from previously cooked food (buildup) or the outside environment. VOC emissions were also exacerbated by reduced air flow in high humidity during rainfall, suggesting an area for further research. The findings underscore the importance of adopting cleaner cooking technologies and enhancing kitchen ventilation to mitigate the impacts of VOCs in developing countries.

Enhancing biochar properties through doping: A comparative study of sugarcane bagasse and chicken feather

This comparative study explores the production and characterization of biochar derived from a combination of sugarcane bagasse (SB) and chicken feathers (CF), with a doping strategy for each biomass in the other. Two biochars, SB92CF-BC (92% SB and 8% CF) and CF92SB-BC (92% CF and 8% SB), were produced using a top-lit updraft reactor, resulting in a yield of 34% and 27%, respectively. Fourier transform infrared spectroscopy (FTIR) analysis revealed characteristic functional groups in both biochars, with minimal impact from the doping process. Scanning electron spectroscopy (SEM) analysis showed distinct morphological features, with SB92CF-BC exhibiting a smoother surface and CF92SB-BC displaying an irregular and rough morphology. Energy dispersive X-ray spectroscopy (EDS) analysis confirmed the presence of several elements in both biochars, with a higher nitrogen content in CF92SB-BC. Brunauer-Emmett-Teller (BET) analysis demonstrated significant specific surface areas for both biochars, exceeding those reported for unmodified SB and CF biochars. The findings suggest potential synergistic effects resulting from the doping strategy. The study expands knowledge on biochar production from diverse biomass sources and highlights the potential for utilizing lignocellulosic and non-lignocellulosic biomass waste materials for sustainable biochar production.

Effect of the air flows ratio on energy behavior and NOx emissions from a top-lit updraft biomass cookstove

Biomass as an energy source for three-stone cookfires is commonly used for cooking and heating rural and isolated households in developing countries; therefore, indoor air quality decreases. In this work, the effect of the air flows ratio (combustion air/gasification air, CA/GA: 2.8, 3.0, and 3.2), and the start type, cold (CS), and hot (HS), on the energy behavior and emissions from a forced-draft top-lit updraft (TLUD) cookstove, using wood pellets as fuel, is studied. Furthermore, the gasification process was thermodynamically characterized. The TLUD cookstove assessment was carried out following a modified water boiling test (WBT). The highest thermal efficiency of the cookstove was 26.74%. The lowest specific CO, NOx, and total suspended particle matter (TSPM) emissions were 1.8 g/MJd, 106 mg/MJd, and 78.32 mg/MJd, respectively; this was attributed to a proper mixture between the producer gas and the combustion air. The gasification process showed a better energy yield under the hot start due to the preheating induced in the cookstove reactor. The optimal values of the producer gas heating value (LHVpg), cold gas efficiency (CGE), and the biochar yield (Ychar) were 3.53 MJ/Nm3, 58.61%, and 12.49%, respectively. Here, an opposite effect was found for the air flows ratios assessed. The cookstove behavior improved as the mixture between CA and GA was suitable, achieving the maximum at CA/GA = 3.0. However, the NOx emissions increased with the increment of CA/GA ratios (from 2.8 to 3.2). Therefore, future works must address the NOx emission reduction without penalizing performance or permanent emissions from the TLUD cookstoves.

Production and characterization of neem leaves biochar: Effect of two different retort carbonization systems

This research investigates the effects of two top-lit updraft retort carbonization systems (biomass fuel-based batch and semi-batch-fed) on the production of neem leaf biochar. The semi-batch system achieved higher temperature peaks and yielded biochar with enhanced properties, including a higher BET-specific surface area (305 m2/g) and pore volume (0.156 cm3/g), indicating improved adsorption capacity. It also resulted in biochar with a higher carbon content and reduced concentrations of other elements. The biochar samples with irregular shapes and rough surfaces are suitable for water treatment, biomolecule separation, energy conversion, and storage. This research recommends further optimization of the carbonization process and evaluation under real-world conditions. The outcomes contribute to a better understanding of neem leaf biochar production and its versatile applications, emphasizing the potential benefits of the studied carbonization systems.

Fluoride removal in batch and column systems using bonechar produced in a top-lit updraft drum gasifier and furnace

Hundreds of millions of people are exposed to excessive levels of fluoride in drinking water, predominately in low-resource communities. Activated alumina is recognized as the best available technology for fluoride removal from drinking water by the United States Environmental Protection Agency, but it has substantial economic and environmental costs. Bonechar is a more environmentally friendly and potentially lower cost alternative adsorbent. Here, fluoride adsorption from groundwater (pH 8.1 ± 0.2) by activated alumina was compared with bonechar primarily produced from bovine bones at peak heating temperatures between 400 and 1100 °C in a modular top-lit updraft drum (TLUD) stove (using a bone-wood mixture) and furnace. TLUD and furnace bonechar produced at peak heating temperatures 650–1000 °C and 400–800 °C, respectively, outperformed activated alumina in batch tests (i.e., required smaller doses to achieve 90% fluoride removal). The impact of using bovine versus swine bones to produce bonechar had a negligible impact on fluoride adsorption. A wide range of peak heating temperatures in the TLUD achieved by varying primary air flow rates and fuel selection (e.g., bone-to-wood mass ratios) produced efficient fluoride adsorbents. This finding demonstrates that a TLUD can be a robust, operationally flexible production system. Fluoride removal by TLUD and furnace bonechars showed strong, negative correlations (R2 ≥0.88) with organic matter content. Bonechar pilot column tests indicated that the mass transfer zone was captured (i.e., immediate fluoride breakthrough was not observed) at an empty bed contact time (EBCT) of 5 min, increasing EBCT to 30 min had a minimal impact on adsorption efficiency, and intermittent operation (3–10 d shut-off periods) decreased effluent fluoride concentrations. Furnace bonechars produced at peak heating temperatures 400–700 °C outperformed activated alumina in pilot columns. Differences in adsorption efficiencies in batch and column tests were associated with the linearity of fluoride adsorption. A theoretical model quantifying adsorption linearity with Freundlich 1/n values was able to predict adsorber performance solely based on batch test data.

Composition and morphology of biomass-based soot from updraft gasifier system

Soot is an aerosol formed by incomplete combustion of carbonaceous materials, and its formation in biomass gasification is inevitable. It is crucial to know the properties of the soot produced in the exhaust of gasification reactors in order to appreciate both its advantages and disadvantages. In this study, a variety of analytical techniques were used to examine the content and morphology of biomass soot produced by a top-lit updraft gasifier. The results of the experiment revealed that carbon and oxygen make up the majority of the soot, with minor amounts of other components. Both aromatic and aliphatic groups with significant oxygen concentrations can be seen in the soot based on the distribution of functional groups. The morphology revealed an uneven, stratified, amorphous sample. Meanwhile, the sample had a surface area of 193.8 m2/g and a pore diameter of 2.68 nm. These porous qualities point to a potential use of the soot sample as an adsorbent in water filtration after activation.

Valorization of waste cassava peel into biochar: An alternative to electrically-powered process

Cassava production and consumption in its raw or processed form have experienced a rise in recent times globally, with Nigeria being the major producer of cassava in the world. However, the increased consumption of this crop has resulted in an increase in its peels, which if not properly disposed of or recycled, would burden the environment. Previous studies have only been able to engage electrically-powered reactors for the thermochemical conversion of these peels, which is a challenge as these reactors cannot be used in regions with an insufficient supply of electricity. In this study, the authors utilized a top-lit updraft reactor with retort heating for the conversion of waste cassava peels into biochar. The reactor, which is relatively cheap, simple to use, and environmentally friendly and modified for biochar production, is biomass-powered. The carbonization process, which lasted for 160 minutes, obtained a peak reactor temperature of 338 ℃, and gave rise to a biochar yield of 55.13%. FTIR analysis revealed that the cassava peel biochar consists of similar functional groups in relation to its precursor, but consists of more oxygenated functional groups. The BET surface area and BJH pore diameter of the biochar were obtained to be 319.784 m2/g and 2.447 nm, respectively. EDX analysis showed the biochar is majorly made up of carbon (56.93%) and silver (22.97%). SEM micrographs revealed that the biochar has a rough and porous surface. The DTA/TGA results showed that the carbonization process improved the thermal efficiency of the cassava peel material.

Conversion of biomass to biochar using top‐lit updraft technology: a review

AbstractThe demand for biochar has increased over time due to its wide range of applications in various industries. Biochar, which is the solid product of the thermochemical conversion of biomass, has been synthesized using different reactor‐based technologies. One such technology is top‐lit updraft (TLUD) technology. This study is a review of published literature that discusses trends in the utilization of the TLUD technology, focusing on biochar production. This study also evaluated the principles of TLUD technology. The properties and applications of TLUD‐based biochar were also discussed. In comparison with other technologies, TLUD technology is characterized by higher thermal efficiency, simplicity of starting the fuel, low smoke emission, and high biochar yield. It was observed that the use of TLUD technology resulted in the production of high‐quality biochar with a variety of characteristics, which has been utilized as an adsorbent for wastewater treatment, in the agricultural sector to increase soil nutrients, and as a solid fuel. The concept of semi‐batch‐fed TLUD technology was also introduced in this study to enhance the efficiency and output of the batch‐fed TLUD configuration that has been in use. Some knowledge gaps in the study could be addressed by future studies on the use of this technology. © 2023 Society of Industrial Chemistry and John Wiley & Sons Ltd.

Comparative Study of Biochars from the Retort Co-Carbonization of Corn Cob and Polyethylene Wastes

Biochar is a pyrogenic, carbon-rich by-product of the products of biomass valorization. Its applications include source of heat, carbon sequestration, soil improvement, adsorbent, chelating agent and niche for micro-organism growth. The study focused on the retort carbonization of corn cob and co-carbonization of corn cob and polyethylene waste for comparative studies using a top-lit updraft conversion reactor with retort heating. The properties of the biochars were analyzed using Scanning Electron Microscopy - Energy Dispersive X-ray (SEM-EDX) and Branueur-Emmet-Teller (BET). Results revealed the ordinary biochar had a homogeneous surface with repeating patterns forming a honeycomb-like structure with a 62% carbon composition while the hybrid biochar had a heterogeneous surface with a rough pattern and ridges with an 80% carbon composition. The heterogeneity and increase in carbon composition observed in the hybrid biochar were attributed to the presence of the polyethylene waste. Biochars with high carbon contents can find their applications in areas of carbon sequestrations. The biochar and hybrid biochar were found to be porous with specific surface areas of 392.5 m2/g and 889.9 m2/g respectively. The high specific surface area of the hybrid biochar produced highlights its potential as an adsorbent. Biochar with high levels of porosity is also useful in soil enhancement. The co-carbonization of corncob and polyethylene waste has been established to be a means of conversion of both agricultural and plastic wastes into biochar with various potential applications.

Experimental Research to Increase the Combustion Efficiency in the Top-Lit Updraft Principle Based Gasifier

The recovery of vegetal waste for energy purposes is one of the ways to increase the amount of energy obtained from renewable sources. The Top-Lit Updraft (TLUD) gasification and combustion process is recognized as the least polluting of all other combustion processes, resulting in a sterile charcoal called biochar, which can be used as an amendment in agricultural soils. The purpose of this research was to determine the influence of excess air in the combustion area compared to the (theoretical) calculated requirement for a TLUD energy module. Most scientific publications on this topic recommend primary/secondary air flow rate ratios of 1/3 or 1/4. In this study, the two recommended ratios were tested, and it was found that better energy results correspond to the ratio of 1/3. For this 1/3 ratio, the investigations continued in order to optimize the combustion process. The results achieved demonstrate that the excess combustion air flow of 30% improves the performance of the energy module due to the increase in oxygen supply and the increase in air speed in the combustion area of the syngas resulting from gasification. Increasing the excess combustion air flow rate by +50% had the effect of lowering the temperature in the flame due to the cooling of the combustion gases caused by a too high rate of excess cold air flow.

Recovery of metallic oxide rich biochar from waste chicken feather

Over the years, the devastating impact of climate change has become pronounced due to inadequate regulation for waste disposal in a developing country like Nigeria. The chicken feather-based metal oxide-rich (MOR) biochar was produced using a top-lit updraft reactor at a peak temperature of 417.2 °C to give a yield of 28.19%. The results were analyzed using Brunauer-Emmett-Teller BET, Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), Energy Dispersive Spectroscopy (EDS), and X-ray fluorescence spectroscopy (XRF). The result shows that the sample is mesoporous (pore diameter of 2.132 nm) with a BET surface area of 105.7 m2/g. CaO (33.147 wt%) and SO3 (25.673 wt%) were the major oxides present in notable proportions on the material surface, which were evident in the SEM micrograph. The major elemental compositions of the raw sample were oxygen (36.917 wt%) and calcium (23.690 wt%), and the major minerals present were quartz, marialite, davyne, and graphite. The present study elucidates the successful and efficient material recovery route for the preparation of adsorbents and precursors for many product synthesis processes.Graphical

Design and simulation of a novel top-lit downdraft gasifier cookstove and performance comparison with a conventional top-lit updraft cookstove

This study designed and fabricated a novel top-lit downdraft gasifier stove (TLDDGS), which was compared with a traditional top-lit updraft gasifier stove (TLUDGS) in terms of modeling and performance. The experimental and simulation results demonstrated that the novel TLDDGS exhibits a downward-flow configuration. The average fuel consumption measured in the experiments was 4.57 ± 0.933 g/min. The average flame temperature from the experiment was 608 ± 43 °C. The TLDDGS mean flame temperature remained stable throughout the experiment. The O2, H2, CO2, CO, CH4, and N2 in the diluted syngas from the experiment were 16.07, 0.33, 0.66, 2.56, 0.34, and 80.04% by volume, respectively. The total suspended particulates and CO in TLDDGS and TLUDGS were 15 and 28 mg/m3 and 335 and 69 ppm, respectively, which are within the limits specified by the local standard. Thus, the developed TLDDGS is a promising alternative for sophisticated cooking applications because of its superior performance in terms of flame stability.

Characterization of biochar and phosphorus adsorption in charnockite-originated soils

Phosphorus, P deficiency by adsorption and fixation of applied P is a critical problem in the tropical soils coupled with wastage of agricultural land and potential nutrients from crop residues’ decomposition necessitates conservancy and sustainable management. Maize stover biochar (mB) and sawmill waste biochar (sB) pyrolysed for 60-minute at 460 °C using Top-Lit Up Draft (TLUD) carbonizer were characterized by morphological, elemental and proximate properties analysed by Scanning Electron Microscope (SEM), CHNS Elemental Analyser and appropriate methods, respectively. Phosphorus (P) adsorption potential of the biochars in charnockite-originated soils were evaluated using adsorption isotherms after adding biochars at 0, 5, 10 and 20% (w/w) with concentrations of 0, 15, 30, 60, 90, 120, 150 mg P/L. SEM showed macropores (>50 nm) embedded biochars, with higher elemental C and H in sB while mB contained higher N, S, O, available P and pH. P-adsorption decreased inconsistently with increasing biochar rates resulting in P-desorption. Low Langmuir adsorption maximum (Qm) were recorded (−0.0350 to 0.1250 mg kg −1 ) mostly with negative separation factors (R L ) and the adsorption process were favourable for mB amended soils having Freundlich heterogeneity factor (n F ) of 4.476–9.634 but not for sB amended soils (n F = 0.638–2.812). Biochar production conserved nutrient loss and potentially reduced soil P fixation.

Co-carbonization of waste biomass with expanded polystyrene for enhanced biochar production

Expanded polystyrene and waste biomass (almond leaves) were investigated in this study as effective feedstocks for the synthesis of biochar. The biochar was created in a top-lit updraft conversion reactor, and its characteristics were examined for potential applications using a variety of analytical techniques. The biochar yields of 39.5 wt% for the biomass and 60.6 wt% for the hybrid system were obtained at peak temperatures of 295 °C and 320 °C, respectively. Samples of biomass biochar and hybrid biochar, with surface areas of 379 and 398.5 m2/g, respectively, showed mesoporous structures. Thermogravimetric analysis showed that the hybrid biochar is more thermally stable than the biomass biochar, while FTIR results revealed the presence of several functional groups in both samples, validating their potential as adsorbents for the removal of pollutants. The study was able to establish practical methods for managing municipal solid waste, a plan for a sustainable environment, and the development of valuable products with a range of potential applications.

Production and Characterization of Wild Sugarcane (Saccharum spontaneum L.) Biochar for Atrazine Adsorption in Aqueous Media

Wild sugarcane (Saccharum spontaneum L.) is an invasive plant species in the Central American region. Due to its low nutrient and water requirements, it can grow fast and displace native species. Therefore, its biomass is considered a waste to prevent the further distribution of the specie. This study investigates the production and characterization of wild sugarcane biochar to provide a use for its waste. The produced biochar was used for atrazine adsorption in aqueous solutions to provide a possible application of this biochar near the water bodies that were often detected to be contaminated with atrazine. The biochar was produced via top-lit updraft gasification with airflow rates between 8 to 20 L/min, achieving yields ranging from 22.9 to 27.5%. Batch experiments revealed that biochar made at 12 L/min presented the best removal efficiency (37.71–100%) and the maximum adsorption capacity (qm = 0.42 mg/g). Langmuir (R2 = 0.94–0.96) and Freundlich (R2 = 0.89–0.97) described the experimental data appropriately. Fourier transform infrared spectroscopy suggested that atrazine removal in wild sugarcane biochar could be mainly due to carboxylic functional groups. In addition, the biochar organic carbon composition contributed to a higher removal capacity in biochar produced at different airflow rates.