Search Results (39)

Domestic wastewater discharge is the major source of pollution in Malaysia. Phytoremediation under hydroponic conditions was initiated to treat domestic wastewater and, at the same time, to resolve the space limitation issue by installing a hydroponic system in vertical space at the site. Water hyacinth (WH) was selected in this study to identify its performance of water hyacinth in removing nutrients in raw sewage under batch operation. In the batch experiment, the ratio of COD_initial/plant_initial was identified, and SPSS ANOVA analysis shows that the number of plant size factors was not statistically different in this study. Therefore, four WH, each with an initial weight of 60 ± 20 g, were recommended for this study. Throughout the 10 days of the batch experiment, the average of COD, BOD, TSS, TP, NH4, and color removal was 73%, 73%, 86%, 79%, 77%, and 54%, respectively. The WH biomass weight increased by an average of 78%. The plants have also improved the DO level from 0.24 mg/L to 4.88 mg/L. However, the pH of effluent decreased from pH 7.05 to pH 4.88 below the sewage Standard B discharge limit of pH 9–pH 5.50. Four WH plant groups were recommended for future study, as the COD removal among the other plant groups is not a statistically significant difference (p < 0.05). Furthermore, the lower plant biomass is preferable for the high pollutant removal performance due to the fact that it can reduce the maintenance and operating costs. Full article

Biochar is a solid product generated through the pyrolysis of biomass materials under anaerobic or hypoxic conditions, and it is characterized by its strong adsorption capacity. To investigate the phosphorus adsorption performance of biochar derived from wheat straw, bamboo, and water hyacinth in wastewater, iron modification treatments were applied to these biochars, and the most effective modified biochar was identified. The physicochemical properties of the modified biochars were characterized using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and scanning electron microscopy (SEM). The results showed that optimal modification was achieved with an iron–carbon mass ratio of 0.70 for wheat straw biochar (Fe-WBC) and 0.45 for both bamboo biochar (Fe-BBC) and water hyacinth biochar (Fe-HBC). The maximum phosphorus adsorption capacities of the three modified biochars were as follows: 31.76 mg g⁻¹ (Fe-WBC) > 27.14 mg g⁻¹ (Fe-HBC) > 25.31 mg g⁻¹ (Fe-BBC). It was demonstrated that the adsorption behavior of Fe-BBC was predominantly multi-molecular layer adsorption, whereas the adsorption behavior of Fe-WBC and Fe-HBC was primarily monolayer adsorption. All three types of modified biochars reached adsorption equilibrium within 30 min, with Fe-WBC exhibiting the best adsorption performance. Analysis revealed that the modified biochars contained a large number of unsaturated C bonds and aromatic rings, indicating relatively stable structures. The surfaces of the modified biochars were rich in hydroxyl and carbonyl groups, which contributed to their strong adsorption properties. Post-modification analysis indicated that iron in the biochars predominantly existed in forms such as goethite (FeOOH) and hematite (Fe₂O₃). The iron content in each type of modified biochar constituted approximately 3.08% for Fe-WBC, 5.94% for Fe-BBC, and 5.68% for Fe-HBC relative to their total elemental composition. Overall, the iron-modified biochars employed in this study significantly enhanced the adsorption capacity and efficiency for phosphorus removal in wastewater. Full article

Water hyacinth (Eichhornia crassipes) is a globally invasive aquatic weed with high biomass productivity and nutrient content, offering potential as a low-cost organic soil amendment. This review synthesizes findings from 35 studies identified through a structured Web of Science search, examining its use as mulch, compost, biochar, and foliar extract. Reported agronomic benefits include improvements in soil organic carbon, nutrient availability (particularly nitrogen and potassium), microbial activity, and crop yields. However, most studies are short-term and conducted under greenhouse or pot conditions, limiting field-scale generalizability. Additionally, reporting of compost composition and contaminant levels is inconsistent, raising concerns about food safety. While logistical and economic feasibility remain underexplored, emerging evidence suggests that with proper processing, water hyacinth amendments could reduce fertilizer dependence and contribute to circular bioeconomy goals. Future research should prioritize field trials, standardized production protocols, and life cycle assessments to evaluate long-term performance, risks, and climate benefits. Full article

Biochar has recently emerged as a promising resource for enhancing crop productivity by improving the soil quality. However, there is limited understanding of how varying application rates of biochar combined with inorganic fertilizers impact crop productivity across diverse biophysical contexts. This study investigated the effects of different rates of water hyacinth-derived biochar and fertilizer application on wheat production during the rainy and dry seasons. Four biochar rates (0, 5, 10, and 20 t ha⁻¹), three NPS fertilizer rates (0, 100, and 200 kg ha⁻¹), and two irrigation levels (50% and 100%; for the dry season only) were evaluated for wheat yield and profitability with a randomized complete block design. Soil amendment with both biochar and fertilizer improved wheat grain yield by 6.4% in the dry season and by 173% in the rainy season. Optimal grain yields were achieved with 10 t ha⁻¹ of biochar and 200 kg ha⁻¹ of fertilizer in the rainy season, whereas in the dry season, the highest yield was observed with 20 t ha⁻¹ of biochar and 200 kg ha⁻¹ of fertilizer under the full water requirement. Specifically, for the dry season, plant height, leaf area, soil plant analysis development (SPAD) of leaf value, dry biomass, spike length, spikelet number, and grain number significantly improved due to biochar and fertilizer application. Furthermore, reducing irrigation to 50% did not significantly affect growth and yield components when the soil was amended with biochar. The highest net return (5351 and 3084 USD ha⁻¹) was achieved with 10 t ha⁻¹ of biochar and 200 kg ha⁻¹ of fertilizer during the rainy and dry seasons, respectively. This study suggests that maximum yield improvement and economic benefits can be obtained through the combination of biochar application, appropriate fertilizer rates, and water management strategies in rainfed and irrigated cropping systems. Full article

Lignocellulosic biomass from water hyacinth, a readily available waste material, holds potential for producing commercial products such as xylose, which can be further converted into value-added products like xylitol. However, the complex structure of lignocellulosic biomass necessitates energy-intensive processes to release fermentable sugars. Chemical pre-treatment methods, such as alkali pre-treatment, offer a viable approach to degrade lignocellulose biomass. In this study, water hyacinth biomass (WHB) was treated with 3% potassium hydroxide and subjected to autoclaving to hydrolyse the sample. The total xylose released during the process was quantified using a UV-Vis spectrophotometer and was found to 0.253 g/g of water hyacinth biomass when the sample was treated for 20 min at 2% biomass concentration. The morphological changes in the treated biomass compared to the untreated sample were analysed using Field Emission Scanning Electron Microscopy (FE-SEM). Crystallinity alterations were evaluated through X-Ray Diffraction (XRD), while Fourier-Transform Infrared Spectroscopy (FTIR) was employed to study the changes in chemical states of the biomass. The primary objective of this study was to identify a reliable pre-treatment method for processing water hyacinth biomass, facilitating the efficient release of fermentable sugars for downstream applications. Full article

The water hyacinth (WH), also known as Eichhornia crassipes, is Bangladesh’s fast-growing and rapidly expanding sustainable aquatic bioenergy feedstock. The WH, as an energy crop, has been harnessed as a phytoremediation agent to purify contaminated water and produce fuel and environmentally friendly products. A country’s economy relies on the availability of raw materials for energy production, cleaning life-supporting abiotic resources for consumption, and the innovation of cost-effective, eco-friendly products. The present study focuses on a three-in-one nexus using the WH to purify polluted water, the (post-purification) biomass to produce clean energy fuels (biogas and bioethanol), and for the manufacture of daily-use products. The ability of the WH, an aquatic macrophyte, to act as a phytoremediator to improve the quality of eutrophic lake water in a laboratory setting was investigated. Water samples were collected from four lakes surrounding the urban community in Dhaka, Bangladesh. The potential to remove salts and solutes and improve the physio-chemical properties of water, including pH, dissolved oxygen (DO), electrical conductivity (EC), total dissolved solids (TDSs), turbidity, and NaCl concentration, were assessed. During the aquatic macrophyte treatment, a 100% WH survival rate was shown, with no visible toxicity symptoms observed in the biomass. The WH improved water quality after one week, as determined by a significant decrease in turbidity, EC, NaCl, and TDSs, and improved pH and DO levels. Here, we establish the WH’s proficiency in removing nutrients/solutes and improving water quality. In addition, we discuss the utilization of this invasive aquatic biomass to produce energy after remediation of water including cost-effective and eco-friendly products to incur daily life with environmental and socioeconomic benefits in Bangladesh. Full article

This study introduces a gamma pretreatment of water hyacinth powder for activated carbon (AC) production with improved electrochemical properties for supercapacitor applications. The structural and morphological changes of post-irradiation were meticulously analyzed using scanning electron microscopy (SEM), Raman spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), Brunauer–Emmett–Teller (BET) analysis, and X-ray photoelectron spectroscopy (XPS). The pretreatment significantly modifies the pore structure and reduces the particle size of the resulting activated carbon (WHAC). Nitrogen adsorption-desorption isotherms indicated a substantial increase in micropore volume with escalating doses of gamma irradiation. Electrochemically, the activated carbon produced from pretreated WH at 100 kGy exhibited a marked increase in specific capacitance, reaching 257.82 F g⁻¹, a notable improvement over the 95.35 F g⁻¹ of its untreated counterpart, while maintaining 99.40% capacitance after 7000 cycles. These findings suggest that gamma-pretreated biomasses are promising precursors for fabricating high-performance supercapacitor electrodes, offering a viable and environmentally friendly alternative for energy storage technology development. Full article

The combined application of biochar and fertilizer has become increasingly popular for improving soil quality and crop productivity. However, the reported research results regarding the effects of biochar on soil properties and crop productivity have contradictory findings, indicating the requirement for further scientific research. Therefore, this study aimed to investigate the effects of a combined application of water hyacinth biochar (WHB) and NPS fertilizer on soil physicochemical properties and wheat yield under deficit irrigation conditions in acidic silty loam soil in Ethiopia. Four different biochar rates (0, 5, 10, and 20 t ha⁻¹), three fertilizer rates (0, 100, and 200 kg NPS ha⁻¹), and two irrigation regimes (50 and 100% of crop requirement) were evaluated to assess soil properties and wheat yields. The results showed that biochar amendment significantly reduced soil bulk density by 15.1–16.7%, and improved soil porosity by 6.8–8.6% and moisture content by 10.3–20.2%. Additionally, the combined application of biochar and fertilizer improved soil pH (0.26–0.87 units), NH₄⁺–N (73.7–144%), NO₃⁻–N (131–637%), and available phosphorus (85.8–427%), compared to the application of fertilizer alone. As a result, wheat dry biomass and grain yield increased by 260 and 173%, respectively. Furthermore, the combined application of WHB and fertilizer resulted in a comparable wheat dry biomass and grain yield even with a 50% reduction of irrigation water. Therefore, WHB has a significant potential to improve soil physicochemical properties and wheat yield when it is applied in combination with fertilizer, and it can reduce the water requirement for wheat production. Full article

Rapid industrial development has led to the use of numerous dyes responsible for significant water pollution worldwide. Adsorbents have been developed to treat these waters, mainly in the form of activated biochar, which has several advantages, one of which is its good surface characteristics, such as high surface area and pore volume. The objective of the investigation was to analyze the efficiency of removing the methylene blue model dye in aqueous solutions through the adsorption process using biochar chemically activated from the leaf and stem of water hyacinth (Eichhornio crassipes) as a bioadsorbent. This study carbonized the stem and leaf containing zinc chloride at 600 °C. The materials were characterized by different techniques and were tested for their ability to adsorb methylene blue. The activated stem and leaf biochars removed approximately 285.71 and 322.58 mg g⁻¹ of the dye, respectively, indicating that the adsorption is more significant in the leaf. Pseudo-second-order kinetics was the most suitable model to describe dye adsorption on biochars, and the experimental isotherm data fit the Langmuir model. It is concluded that the application of activated water hyacinth biochar is a renewable resource with the potential for effluent treatment. Full article

Second-generation lactic acid production requires the development of sustainable and economically feasible processes and renewable lignocellulose biomass as a starting raw material. Weizmannia coagulans MA42 was isolated from a soil sample in Chiang Mai province, Thailand and showed the highest production of L-lactic acid and lignocellulolytic enzymes (cellulase, β-mannanase, xylanase, β-glucosidase, β-mannosidase, and β-xylosidase) compared to other isolates. Weizmannia coagulans MA42 was able to grow, secrete lignocellulolytic enzymes, and directly produce L-lactic acid in the medium containing various lignocellulosic feedstocks as the sole carbon source. Moreover, L-lactic acid production efficiency was improved after the substrates were pretreated with diluted sulfuric acid and diluted sodium hydroxide. The highest L-lactic acid production efficiency of 553.4 ± 2.9, 325.4 ± 4.1, 326.6 ± 4.4, 528.0 ± 7.2, and 547.0 ± 2.2 mg/g total available carbohydrate was obtained from respective pretreated substrates including sugarcane bagasse, sugarcane trash, corn stover, rice straw, and water hyacinth. It is suggested that structural complexity of the lignocellulosic materials and properties of lignocellulolytic enzymes are the key factors of consolidated bioprocessing (CBP) of lignocellulosic feedstocks to lactic acid. In addition, the results of this study indicated that W. coagulans MA42 is a potent bacterial candidate for CBP of a variety of lignocellulosic feedstocks to L-lactic acid production; however, further bioprocess development and genetic engineering technique would provide higher lactic acid production efficiency, and this would lead to sustainable lactic acid production from lignocellulosic feedstocks. Full article

Cellulase and xylanase have been widely studied for bioconversion processes and applied in various industries. The high cost of these enzymes remains to be the major bottleneck for large-scale commercial application of lignocellulosic biorefinery. The use of agroindustrial residues and weeds as fermentation substrates is an important strategy to increase cellulolytic enzymes production and reduce costs. Penicillium crustosum was newly isolated and selected to study its enzyme production during solid-state fermentation (SSF). Natural and pretreated water hyacinth (WH) biomass was used as support, substrate and inducer of cellulases and xylanases. Thermochemical pretreatments of WH biomass at 121 °C and sulfuric acid at three concentrations (0.2, 0.6 and 1 M) were assayed. The pretreatments of WH biomass released mono- and oligo-saccharides that favored fungal growth and enzymes production on SSF. WH is a cost-effective substrate-support and inducer, which to be used as a solid medium, was impregnated with a saline solution, containing only (NH₄)₂SO₄, KH₂PO₄ y MgCl₂. Maximum cellulases (carboxymethylcellulase (CMCase)) and xylanases productions of P. crustosum cultured on SSF were reached using the WH pretreated biomass with H₂SO₄ 0.6 M and 121 °C. The simultaneous CMCase and xylanases production reached (647.51 and 4257.35 U/g dry WH, respectively) are among the highest values ever reported. Full article

Nowadays, several alternatives have been proposed to increase the porosity and/or modify the surface groups of hydrochars from biomasses as well as to develop additional features on them. These alternatives can include specific modifications for the process, as previous steps or as postreatments, and the wide variety of forms in which they can be made can substantially affect the product distribution and properties. In this study, the hydrothermal carbonization process of an invasive floating plant (Water hyacinth) has been modified by introducing different amounts of iron (FeCl₃) and aluminium alloy (shaving scrap waste) during the hydrothermal reaction. The effects on process reactivity, phase distribution, and physicochemical properties of the samples obtained were studied by means of different characterization techniques such as thermogravimetry (TG-DTG), physical adsorption/desorption of N₂ at −196 °C, FT-IR spectroscopy, and scanning electron microscopy (SEM). In the case of iron-catalyzed reactions, the magnetite formation and magnetic behavior of the prepared hydrochars after a pyrolytic treatment was also estimated. The results obtained indicate that the porosity of the hydrochars was clearly improved to different extents by the addition of Al or Fe during direct synthesis. In addition, porous carbons with a moderate magnetic character were obtained. Full article

In the current study, dried ground mixed waste of olive waste and water hyacinth was subjected to the treatment of wastewater contaminated with stable or radioactive cobalt and cesium. Contact time, temperature, amount of adsorbent, metal ion concentration and pH-value were evaluated as the most potent factors that affect the adsorption process. Concentrations of Co and Cs ions before and after treatment are measured using ICP-OES technique. Moreover, kinetic and equilibrium isotherm parameters were investigated by explaining the equilibrium data by induction of two isotherms, “Langmuir” and “Freundlich”. Experimental results indicated that more than 85% of ⁶⁰Co and ¹³⁴Cs were efficiently removed from spiked wastewater after one hour of contact time by using 0.2 g of dried mixed waste. The optimal time to remove Cs⁺ and Co²⁺ was 50 and 90 min, respectively. The kinetic study showed that the adsorption of Cs⁺ and Co²⁺ were better suited to the second order. The most favorable pH value was at a range of 6–7 for Cs⁺ and 5–6 for Co²⁺. R² values were higher at the Freundlich isotherm, indicating that the adsorption process was taking place according to Freundlich isotherm at all temperatures for Co²⁺ and Cs⁺ ions. Full article

We have successfully prepared porous carbon from water hyacinth plants using several steps, i.e., carbonization, activation, and calcination processes. Water hyacinth porous carbon is an alternative as a carbon material due to the ease and low cost of the manufacturing process, abundant raw materials in nature, and its contribution to solving environmental problems. Utilization of water hyacinth weed plants as raw materials for porous carbon will provide added value to water hyacinth. In this research, porous carbon is used as the host material of sulfur in the electrodes of lithium sulfur batteries. The N₂ adsorption desorption characterization showed a porous carbon surface area of around 642 m²/g and a total pore volume of 0.713 cm³/g. The sulfur content of the composite electrode of C/S 1:2.5 (%w/w) was 60.6%. The four-line probe (FLP) testing showed electrical conductivity of porous carbon of around 3.93 × 10⁻² S/cm and the electrical conductivity of the composite electrode was around 5.4 × 10⁻⁴ S/cm. Furthermore, the composite electrodes were applied as cathodes of lithium sulfur batteries, which have thicknesses around 200 µm and sulfur loading of 3.57 mg/cm². The highest discharge capacity of the battery was 312 mAh/g and the Coulombic efficiency was around 70%. Full article

A novel, integrated system is proposed for the cultivation and co-digestion of the invasive macrophyte water hyacinth (WH) with cow manure (CM) for the production of biogas for cooking in rural India. This study investigates the pre-treatment approaches and performs a techno-economic analysis of producing biogas in fixeddome digesters as a replacement for liquefied petroleum gas (LPG). Methodologies have been developed for the cultivation of WH collected from wild plants in the Indrayani River, Pune, India. Cultivation trials were performed in 350 litre tanks using water, which was nutrient fed with CM. Cultivation trials were performed over a 3 week period, and growth rates were determined by removing and weighing the biomass at regular time intervals. Cultivation results provided typical yields and growth rates of biomass, allowing predictions to be made for cultivation scaling. Samples of cultivated WH have been co-digested with CM at a 20:80 ratio in 200 L anaerobic digesters, allowing for the prediction of bio-methane yields from fixed-dome anaerobic digesters in real world conditions, which are commonly used in the rural locations of India. A calculator has been developed, allowing us to estimate the scaling requirements for the operation of an integrated biomass cultivation and anaerobic co-digestion unit to produce an equivalent amount of biogas to replace between one and three LPG cylinders per month. A techno-economic analysis of introducing WH into fixed-dome digesters in India demonstrated that the payback periods range from 9 years to under 1 year depending on the economic strategies. To replace between one and three LPG cylinders per month using the discussed feedstock ratio, the cultivation area of WH required to produce sufficient co-feedstock ranges within 10–55 m². Full article