Search Results (77)

Marine oil spills have caused significant environmental problems. Among the array of clean-up methods, the utilization of sorbents emerges as promising for removing and recovering oil from spills. Developing cost-effective, reliable, and eco-friendly material that efficiently and sustainably removes oil from water is increasingly seen as crucial and pressing. In the present study, we report the development of coco-polyurethane (PU) foam (CCF) through the conventional foaming process using varying amounts of coconut-oil-derived polyol (CODP) in a PU matrix. Characterization of the foams showed an increased ester band with the incorporation of COPD into the polyurethane networks and no direct influence of the cell size distribution on the surface morphology. Furthermore, this study highlighted the increasing CODP in every CCF formulation, showing high oil sorption and low water uptake due to its porous structure. The experimental results revealed that CCF is a potential candidate sorbent for the recovery of spilled oil. This signifies a significant leap towards reducing the dependency on petroleum in developing sorbent materials and advancing sustainable responses to oil spills in marine environments. Full article

Oil spills represent a significant environmental threat due to the toxicity of hydrocarbons, particularly in aquatic environments where oil rapidly spreads across the surface. Sustainable sorbents are needed for an efficient and eco-friendly response to oil spills. Cellulose aerogels produced from recycled paper and cardboard exhibit promising properties such as buoyancy, light weight, biocompatibility, and recyclability. Mechanical stability and reusability can be enhanced using cross-linkers such as starch. This study evaluated the impact of starch on cellulose aerogel morphology, sorption capacity for various petroleum products (crude oil, marine diesel, and lubricating oil), and reusability using scanning electron microscopy (SEM) and elemental mapping. Aerogels containing 0.5 and 1 wt% starch showed higher porosity, sorption capacity, and reusability. Starch did not affect hydrophobization or significantly alter nitrogen and carbon levels, indicating limited influence on surface chemistry and adsorption performance. Full article

One of the most pressing issues confronting modern society is carbon dioxide pollution (CO₂). The reliance of social progress on CO₂-producing technologies such as power generation, automobiles, and specialized industrial processes exacerbates the problem. Due to this reliance, it is critical to develop solutions to reduce CO₂ emissions from these sources. One such solution is carbon capture and sequestration (CCS), which employs chemical methods to prevent CO₂ emissions. The irreversibility of current CCS technology is its primary problem. Chitin, chitosan, and their derivatives, which were recovered from local seafood waste, are studied as reversible CO₂ capture materials in this study in an effort to lessen this issue. Polysulfone (PSF) blends were employed to lessen chitosan edema, as chitosan’s hydrophilicity reduces its active sorption surface. Blends with only 20% chitosan have the same high sorption capacity as pure chitosan due to decreased swelling. Hydrolysis was used to boost the chitin sorption abilities. The CO₂ sorption data were analyzed using an Intelligent Gravimetric Analyzer (IGA), Fourier-Transform Infrared (FTIR) spectroscopy, and Matrix-Assisted Laser Desorption/Ionization-Time of Flight (MALDI-TOF) spectroscopy. This study reveals that shrimp shells were the best source of chitin. This research led to the creation of eco-friendly, reversible, and reusable carbon sequestration sorbents. Full article

This study reports the synthesis of activated carbon from dwarf elder, a lignocellulosic precursor, yielding a material with a high specific surface area (500.43 m²/g) and mesoporous structure (median pore radius: 3.88 nm). The physicochemical properties of the obtained carbon were characterized using field-emission scanning electron microscopy (FE-SEM), Brunauer–Emmett–Teller (BET) analysis, and Fourier-transform infrared spectroscopy (FTIR), confirming its suitability for aqueous-phase sorption applications. Batch experiments demonstrated carbon’s efficacy in adsorbing amlodipine besylate (AMB), a model pharmaceutical pollutant, with a maximum capacity of 325.9 mg/g under optimized conditions (pH 10.0, room temperature). Systematic evaluation of key parameters, such as initial AMB concentration, sorbent dosage, pH, and agitation speed revealed that sorption kinetics adhered to pseudo-second-order and Elovich model. The high efficiency of the synthesized carbon material, coupled with its low-cost and eco-friendly synthesis, positions it as a promising candidate for the scalable remediation of AMB and structurally related pharmaceuticals from contaminated water sources. Full article

This study presents an innovative, eco-friendly approach for converting waste zeolite dust into efficient petroleum sorbents through an integrated agglomeration–deagglomeration process using high-pressure grinding rolls (HPGRs). This method generates secondary porosity without calcination, enhancing sorption while reducing greenhouse gas emissions and supporting sustainable development by valorizing industrial by-products for environmental remediation. The study aimed to assess the influence of binder and water content on petroleum sorption performance, textural properties, and mechanical strength of the produced sorbents, and to identify correlations between these parameters. Sorbents were characterized using mercury porosimetry (MIP), sorption measurements, mechanical resistance tests, scanning electron microscopy (SEM), and digital microscopy. Produced zeolite sorbents (0.5–1 mm) exceeded the 50 wt.% sorption threshold required for oil spill cleanup in Poland, outperforming diatomite sorbents by 15–50% for diesel and 40% for used engine oil. The most effective sample, 3/w/22.5, reached capacities of 0.4 g/g for petrol, 0.8 g/g for diesel, and 0.3 g/g for used oil. The sorption mechanism was governed by physical processes, mainly diffusion of nonpolar molecules into meso- and macropores via van der Waals forces. Sorbents with dominant pores (~4.8 µm) showed ~15% higher efficiency than those with smaller pores (~0.035 µm). The sorbents demonstrated amphiphilic behavior, enabling simultaneous uptake of polar (water) and nonpolar (petrochemical) substances. Full article

Defluoridation of water was investigated in an adsorption column study using Al-Mg-Ca-coated sand (AMCCS), a ternary metal oxide adsorbent with eco-friendly components that were shown to be effective for water defluoridation, in a batch adsorption study. A packed column of the AMCCS sorbent was evaluated as function of column flow rate, solution type, and sorbent recyclability. Adsorption column experiments included two column flow rates of 2 mL/min and 10 mL/min using two different solutions: deionized water and a synthetic solution representative of groundwater. Greater fluoride column adsorption capacity was obtained at the lower flow rate for both solutions, mainly due to longer contact times between solution and AMCCS sorbent. Adsorption of fluoride occurred through physical adsorption, which followed the Langmuir adsorption model and second-order kinetics for deionized water and synthetic solution. A lower AMCCS column fluoride adsorption capacity was observed for the synthetic solution due to the competition from adsorption of other ions in the synthetic solution, whereas fluoride adsorption by the AMCCS column was influenced by interphase mass transfer to a lesser extent using the synthetic solution than deionized water. The re-coating of spent AMCCS sorbent in the adsorption column resulted in effective recycling and reuse of the AMCCS adsorption column for both deionized water and the synthetic solution, rendering the AMCCS adsorption column a recyclable and sustainable flow through water defluoridation system. Full article

This study presents a sustainable approach to recycling exhausted etching solutions through ferritization, using various activation methods and aeration rates. The process transforms industrial waste into valuable magnetic sorbents, supporting circular economy principles. Structural and chemical analysis of the ferritization products revealed the formation of ferromagnetic crystalline phases, including lepidocrocite (ɣ-FeOOH), ferrooxygite (δ-FeOOH), and magnetite (Fe₃O₄). Increasing the aeration rate and use of ultrasound treatment enhances Fe₃O₄ content and iron ion removal efficiency. The adsorption capacity of the recycled materials for Zn²⁺ removal was assessed under different pH conditions using mechanical mixing and ultrasound treatment. The highest level of Zn²⁺ removal (92.0%) was achieved at pH 8 with ultrasound-activated sorbents containing 61.3% δ-FeOOH and 38.7% Fe₃O₄. At pH 10, magnetite-based sorbents achieved over 98.9% Zn²⁺ removal, enabling the treated water’s reuse in industrial rinsing processes. Electron microscopy and X-ray fluorescence confirmed the presence of fine, spherical magnetite and zinc ferrite particles. These findings underscore the potential of ferritization-based recycling as an eco-friendly and efficient strategy for heavy metal removal from galvanic wastewater. Full article

The frequent detection of trichothecenes in grains highlights critical health risks to humans and animals. Based on the hybrid sorbent strategies, this study developed an innovative multifunctional column (ASAG563) integrating extraction, purification, and filtration to address limitations of existing methods, including cumbersome process, protracted duration, harmful to the environment, and significant matrix interference. Coupled with high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS), the ASAG563 column demonstrated superior recoveries (80.8–117.8%) and quantification limits (2.02~48.41 µg/kg) across cereals and feeds, with low relative standard deviations (<6.8%). Compared to commercial MFCs, the ASAG563 column simplified the process, reduced material consumption, saved 50% of analysis time, and effectively eliminated matrix effects. Analysis of 512 maize for feedstuff samples from Northeast China revealed significant contaminations with deoxynivalenol (DON) and its derivatives, emphasizing the necessity for enhanced regulatory measures. This novel integrated multifunctional pretreatment column presents a convenient, cost-effective, and eco-friendly solution for accurate TCT detection, significantly advancing analytical capabilities. Full article

Freshwater scarcity is a growing concern, exacerbated by industrial effluents containing dyes and other pollutants that endanger aquatic ecosystems. This study explores the potential of biochar sorbents, derived from renewable seaweed biomass, as a sustainable solution for water decontamination. Seaweed biomass (sargaço), collected from Portuguese seashores, was carbonized at 300 °C and 400 °C to produce biochar. Adsorption experiments with methylene blue (MB) revealed that carbonization at 400 °C, followed by ball milling, significantly enhanced adsorption performance. Langmuir isotherm analysis demonstrated a maximum adsorption capacity of 500 mg MB/g sorbent for the optimized biochar (400 °C, ball milled), with adsorption efficiency improving at elevated temperatures and pH levels up to 12. Infrared reflectance spectra of fresh and post-adsorption biochars confirmed the involvement of π–π interactions and hydrogen bonding in the adsorption mechanism. These findings highlight the potential of seaweed-derived biochar as an effective and eco-friendly solution for water purification. Full article

Adsorption represents an effective strategy for water remediation applications, particularly when utilising eco-friendly materials in a circular economy framework. This approach offers significant advantages, including low cost, material availability, ease of operation, and high efficiency. Herein, the performance of cadmium ion adsorption onto hydroxyapatites, derived through a calcination-free process from shells of two mollusc species, Queen Scallop (Aequipecten opercularis) and Pacific Oyster (Magallana gigas), is examined. The phase and morphology of the synthesised adsorbents were investigated. The results showed that hydroxyapatites obtained from mollusc shells are characterised by high efficiency regarding cadmium removal from water, exhibiting rapid kinetics with equilibrium achieved within 5 min and high adsorption capacities up to 334.9 mg g⁻¹, much higher than many waste-based adsorbents reported in literature. Structural investigation revealed the presence of Cadmium Hydrogen Phosphate Hydrate in the hydroxyapatite derived from oyster shells loaded with Cd, indicating the formation of a solid solution. This finding suggests that the material not only has the capability to decontaminate but also to immobilise and store Cd. Overall, the results indicate that hydroxyapatites prepared via a synthetic route in mild conditions from waste shells are an economical and efficient sorbent for heavy metals encountered in wastewater. Full article

The increasing contamination of water bodies by fats, oils, and grease (FOG) poses significant environmental and operational challenges, necessitating the development of advanced remediation technologies. Aerogels, with their ultra-lightweight structure, high porosity, and tunable surface chemistry, have emerged as promising sorbents for efficient FOG removal. This comprehensive review explores recent advancements in aerogel materials, highlighting novel formulations, functional modifications, and nanotechnology integrations that enhance sorption capacity and reusability. It delves into the mechanistic aspects of FOG sorption, providing insights into how surface interactions and structural properties influence performance. The sustainability of aerogels is emphasized, particularly the use of bio-based and eco-friendly materials that align with green remediation strategies. A comparative analysis with conventional sorbents underscores the advantages of aerogels in terms of efficiency, environmental impact, and cost-effectiveness. Furthermore, real-world applications, including oil spill cleanup and wastewater treatment, are discussed alongside challenges, regulatory considerations, and future research directions. By offering a holistic perspective on the potential of aerogels in water remediation, this review serves as a valuable resource for researchers and industry professionals seeking innovative and sustainable solutions for FOG management. Full article

This study explored the use of chicken feathers, a low-cost and abundant agricultural byproduct, as a sorbent for the removal of reactive yellow dye from aqueous solutions. The dual potential of feathers as both adsorbents and sorbents, attributed to their keratin-rich structure, was utilized to investigate their effectiveness in dye removal. Feathers, activated with 1.0 mol/L HCl, exhibited a maximum adsorption capacity at 70 °C and pH 5.5, as determined from Langmuir isotherm modeling. A 2² central composite rotatable design revealed that temperature and pH significantly influence the adsorption efficiency, with higher temperatures favoring the process. Kinetic studies demonstrated pseudo-first-order behavior, with rapid initial adsorption reaching equilibrium within 120 min. Thermodynamic analysis confirmed the endothermic nature of the process (ΔH° = 28.04 kJ mol⁻¹), a positive entropy change (ΔS° = 66.62 J/mol·K), and a reduction in Gibbs free energy (ΔG°) with increasing temperature, suggesting enhanced feasibility at elevated temperatures. This research highlights the potential of utilizing poultry industry residues as sustainable and efficient sorbents for environmental remediation, contributing to waste valorization and eco-friendly wastewater treatment solutions. Full article

Miniaturized solid-based approaches have added an eco-friendly dimension to analytical procedures, establishing themselves as promising strategies for a wide range of applications. Among these, microextraction by packed sorbent (MEPS) stands out due to its ability to facilitate efficient sample interaction with a densely packed sorb ent phase within the microextraction system. MEPS offers several advantages, including preconcentration capabilities and the use of minimal sample and solvent volumes, making it an appealing choice for modern analytical workflows. Since the extraction efficiency is largely dictated by the sorbent phase, recent advancements in sorbent design have garnered considerable attention in the field of sample preparation. Innovations in sorbent phases have not only enhanced the MEPS efficiency but also enabled the development of semi- and fully automated systems, paving the way for high-throughput methodologies. These advancements have elevated MEPS beyond traditional offline miniaturized sample preparation methods, offering new opportunities for streamlined and scalable analyses. Therefore, this study provides a comprehensive overview of novel sorbent phases used in MEPS, with a particular focus on both bio-based and synthetic materials. Furthermore, it explores the semi- and fully automated aspects of MEPS, highlighting current trends, technological advancements, and future directions in this rapidly evolving field. Full article

Cement kiln dust (CKD), a by-product of cement manufacturing, has been largely underutilized despite its potential as an eco-friendly adsorbent for wastewater treatment. This study addresses the knowledge gap regarding CKD’s effectiveness in removing heavy metals from wastewater residuals. A comprehensive experimental program was conducted to optimize key parameters such as the pH (6–9), contact time, sorbent dosage, and initial heavy metal concentrations using a batch equilibrium technique. The results demonstrated that CKD can effectively remove heavy metals, achieving removal efficiencies of 98% for Pb, 94% for Zn, 92% for Cu, and 90% for Cd within just 4 h of treatment. Importantly, CKD not only provided high adsorption efficiency but also resulted in a significant reduction in the formation of hazardous solid sludge, a major concern in traditional wastewater treatment methods. The adsorption data closely matched the Langmuir isotherm model, further validating CKD’s potential as a sustainable, cost-effective solution for reducing heavy metal contamination in wastewater while minimizing the environmental impact. Full article

This article reports the obtention of a new gellan-based hydrogel linked with Fe³⁺ and loaded with a natural micro/nanostructured carbon designed as a contaminant’s removal from wastewater. Hydrogels are known for their water-retaining properties, high binding capacity, and eco-friendly features. The new material is expected to behave as one cost-effective and efficient sorbent, including natural carbon structures with various functional groups. The encapsulation efficiency ranges between 89% and 95%. The obtained hydrogel particles were characterized using FT-IR spectroscopy and scanning electron microscopy techniques. The hydrogel particles’ water stability was evaluated by measuring the transmittance for 10 days, and the capacity to retain water was assessed by determining the swelling degree (Q%). The results showed that hydrogel particles are stable (the transmittance value is higher than 97.8% after 10 days), and their properties are influenced by the cross-linking degree, the amount of the carbon particles encapsulated, and the concentration of gellan. For example, the Q% values and encapsulation efficiency increased when the cross-linking degree, the carbon microstructure quantity, and the gellan concentration decreased. The new hybrid material can retain Pb(II) ions and diclofenac molecules, and could be used in different adsorption–desorption cycles. Full article