Nature Of Adsorption Research Articles

Adsorption characteristics and mechanism of novel ink melanin composite modified chitosan for Cd(II) in water

In this study, chitosan (CS), carboxymethyl chitosan (CMCS), and chitosan quaternary ammonium salt (HACC) were successfully loaded with ink melanin (ME) as efficient adsorbents for Cd(II) removal. The results of batch adsorption experiments and structural characterization showed that the modified CS loaded with ME improved the adsorption capacity of the composites for Cd(II). The pseudo-second-order kinetic and Langmuir equations were better suited to describe the batch adsorption experiments. The adsorption of Cd(II) was chemisorption with desirable adsorption effect when the concentration of the three composites was 0.5 mg/mL and the pH value was neutral. Among them, HACC-ME demonstrated remarkable Cd(II) adsorption performance (107.18 mg/g) and sustained an 85 % efficiency in Cd(II) removal over five adsorption-desorption cycles. Ion exchange, complexation, electrostatic attraction, and hydrophobic interaction were the primary mechanisms for Cd(II) removal. Overall, HACC-ME could be employed as a low-cost and highly efficient new natural adsorbent material for the removal of Cd(II) ions from wastewater. These findings illuminate pathways for the development of efficient and novel natural adsorbent materials for environmental cleanup purposes.

Simulation and modeling of methylene blue dye removal by an agri-food waste (Peanut shells)

Our study explores the potential of utilizing peanut shells, an abundant and low-cost food waste, as a natural adsorbent for the removal of industrial dyes, specifically methylene blue. We conducted a detailed investigation of the adsorption process, which revealed that it conforms to both Langmuir and Freundlich isotherms, indicating the ability of peanut shells to adsorb methylene blue effectively. To optimize the adsorption yield, we employed a Box-Behnken experimental design. This approach allowed us to assess the impact of several key factors, including the mass of the adsorbent, dye concentration, pH, temperature, stirring rate, and the ionic strength of salts in the solution. The mathematical model and simulation of the adsorption process helped us identify the best conditions for maximizing the dye removal. Our experiments resulted in a maximum adsorption efficiency of 97%, achieved under optimal conditions: 1.5 g of adsorbent, a methylene blue concentration of 40 mg/L, pH 11, temperature of 65°C, 0 mg/L ionic strength, and a stirring rate of 165 rpm. These findings suggest that peanut shells are a viable, eco-friendly alternative for dye removal, offering a sustainable solution for wastewater treatment and contributing to waste reduction.

Cnicus Benedictus roots as a low-cost adsorbent for methylene blue dye removal from aqueous solution: kinetic and equilibrium studies

In this research, Cnicus Benedictus roots powder (CBRP) was utilized as a low-cost adsorbent for removing methylene blue (MB) as a cationic dye from aqueous solution. Characterization of CBRP by Boehm titration method, Fourier transform infrared (FT-IR) and environmental scanning electron microscope (ESEM) indicates the presence of different types of functional groups and a very rough surface filled with cavities, suitable for MB adsorption. The effect of various parameters such as CBRP dose (0.2–2 g/1L), contact time (0–180 min), initial pH (1–10), coexisting anions/cations and the initial MB concentration (100–500 mg L−1) on MB adsorption were examined, the results showed that MB uptake depends on the pH of solution, the electrostatic attraction forces, the formation of H-bonds and π–π interactions are the possible CBRP–MB interaction mechanisms. Adsorption kinetic of MB on CBRP was best represented by linear and non-linear form of the pseudo-second order model. The experimental equilibrium data were best described by linear and non-linear forms of Langmuir and Redlich–Peterson isotherm models (R 2> 0.98) with a maximum MB adsorption capacity of 85.47 mg g−1 at 25 °C, the adsorption efficiency R (%) was greater than 90 (%). MB adsorption-desorption experiments showed the reusability of CBRP for five consecutive cycles. According to the obtained results, CBRP can be used as a natural adsorbent material for cationic dyes removal from aqueous solution.

Exploiting RSM and ANN modeling methods to optimize phosphate ions removal using LDH/alginate composite beads

In the present work, layered double hydroxide (MgAl) and alginate composite beads (LDH/alginate) were developed and used as low-cost and environmentally friendly adsorbent for phosphate ions removal. The successful incorporation of sodium alginate into the LDH structure was confirmed through SEM analysis. The dried beads exhibited a notably rough surface, which promotes molecular movement and potentially enhances pollutant adsorption. The pH of zero charge point (pHPZC) of the composite was found to be 7.41. This result implies that negative ions have a tendency to draw positive charges on the adsorbent surface via electrostatic interaction forces when the pH is lower than the pHPZC. On the other hand, a surface that has a pH higher than pHPZC mostly has a negative charge. The percentage removal and adsorption capacity were investigated as a function of contact time.Experiments were carried out by simultaneously varying three factors, in order to evaluate and compare the predictive capabilities of the response surface methodology (RSM) and the artificial neural network approach (ANN) for the adsorption process. Both methods demonstrated a strong ability to accurately predict the adsorption process. However, the response surface methodology exhibited a lower prediction error compared to the artificial neural network approach.The central composite design within response surface methodology (CCD-RSM) was employed to optimize the experimental conditions for the adsorption process. The model, which considers three factors: adsorbent dose (A), initial concentration (B), and contact time (C), proved to be significant. Among these, the quadratic term (B2) had the most substantial impact on the phosphate ion adsorption rate. The analysis yielded an R2 value of 0.94, indicating an excellent fit to the data. The findings suggest that increasing contact time and reducing the initial concentration improve phosphate ion removal efficiency, while the adsorbent dose has little to no effect. The Artificial Neural Network (ANN) model effectively predicted the adsorptive remediation of phosphate ions onto LDH/alginate composite beads, achieving a high coefficient of determination (R2 = 0.984) between the model outputs and the experimental data. The study highlights the significant potential of LDH/alginate composite beads as a natural adsorbent for the removal of phosphate ions from aqueous solutions. These results underscore the environmental friendliness and efficiency of the adsorbent used for phosphate adsorption.

Estimation and Comparison of Deflouridation of Flouridated Ground Water Using Four Natural Adsorbents: Multani Mitti, Chalk Powder, Orange Peel Powder and Ragi Powder

This study highlights the global issue of fluoride contamination in drinking water, affecting approximately 260 million people in 30 countries, with India facing significant challenges as endemic fluorosis impacts around one million individuals across 17 states. The elevated fluoride levels are primarily attributed to fluoride-bearing minerals in local rocks and soils. The World Health Organization recommends maintaining fluoride concentrations near 1 mg/L to balance dental health benefits while preventing fluorosis. In response, various defluoridation methods—such as precipitation and adsorption—are implemented in India to adjust fluoride levels to optimal ranges. Given the essential role of water in physiological processes for humans, animals, and plants, understanding the variable quality of surface and groundwater is crucial. This variability is influenced by local geological factors and the presence of contaminants, necessitating effective management strategies for safe drinking water access.

Use of Brushite as Adsorbent for the Removal of Anionic and Cationic Dyes Present in Aqueous Solutions

Currently, water pollution caused by dyes is a serious problem since they are toxic and carcinogenic to living beings. To reduce the presence of these contaminants, natural adsorbents have been considered as they are easy to obtain, inexpensive, and have high removal efficiency. In this work, the adsorption process using natural brushite (nDCPD) was studied for the removal of phenol red (PR), achieving a removal rate of 99.15% and an adsorption capacity of 82.24 mg/g, and gentian violet (GV), achieving a removal rate of 97.03% and an adsorption capacity of 74.22 mg/g. Equilibrium adsorption occurs for both dyes in multiple layers on the surface. The adsorption process is spontaneous for both dyes. The kinetics of the adsorption process involve using a single active site on the surface for PR adsorption, while for GV, two active sites on the surface are required. Analysis via FTIR, EDS, and XRD revealed various mechanisms that intervene in the adsorption process of both dyes on the surface of nDCPD, such as electrostatic forces, functional groups, physisorption, and ion exchange.

Examining the influence of sintering temperatures on the efficiency of 3D-printed natural zeolite for methylene blue dye adsorption

Additive manufacturing technology, with its potential for improved material efficiency, cost reduction, and capability to fabricate complex structures, is increasingly being leveraged in environmental engineering applications. This study harnesses this technology for fabricating natural zeolite adsorbents using an extrusion-based 3D printer, examining the influence of different sintering temperatures (300, 600, 900, and 1200 °C) on the adsorbents' properties. The study finds that samples sintered at 300 °C disintegrated in water, while those at 1200 °C underwent melting, changing their shape. Focus was then shifted to samples sintered at 600 °C (3D-Ze-600) and 900 °C (3D-Ze-900), with the former displaying a remarkable methylene blue (MB) adsorption efficiency of 82.5%, significantly higher than the latter's 20.1%. This disparity in adsorption performance is closely linked to the difference in porosity; the 600 °C samples exhibited a notably higher apparent porosity, which was instrumental in their enhanced adsorption capability. In contrast, the 900 °C samples, despite their lower porosity, showed diminished adsorption efficiency. XRD analysis further revealed that the superior performance of the 600 °C samples could be attributed to their preserved crystalline structure, which was altered in the 900 °C samples. These findings highlight the critical role of sintering temperature in determining the structural and functional properties of 3D-printed zeolites, demonstrating their potential as efficient adsorbents in wastewater treatment and offering valuable insights for optimizing the fabrication process for environmental applications.

Enhanced sequestration of ciprofloxacin from aqueous solution using composite montmorillonite-kaolin clay adsorbent

Clay minerals are low-cost and environmentally benign natural adsorbents with huge potential for removing micropollutants from aqueous solutions owing to their intrinsic surface properties. In this study, montmorillonite and kaolin clay minerals were activated using NaNO3 and HNO3 to develop activated montmorillonite- kaolin clay composites (AMKCC) material for the sequestration of ciprofloxacin (CIP) from aqueous solution. The developed AMKCC was characterized using X-ray fluorescence (XRF), Brunauer-emmett-teller (BET), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), X-ray diffractometer (XRD) and X-ray photoelectron spectroscopy (XPS). The BET analysis reveals an improved BET surface area, pore volume and pore diameter of 139.13 m2/g, 0.17 cm3/g and 2.18 nm, respectively. At optimum conditions, pH (3.56), initial concentration (16.74 mg/L), time (77.9 mins) and adsorbent dosage (0.4 g), the percentage of ciprofloxacin removed from aqueous solution was 97 %. The adsorption of ciprofloxacin (CIP) using AMKCC was spontaneous, feasible, endothermic, and followed Freundlich isotherm with pseudo-second-order kinetics. The maximum monolayer adsorption capacity of AMKCC is 344.82 mg/g. The desorption studies revealed HCl as the best eluent for AMKCC regeneration. Therefore, AMKCC has considerable potential for the adsorption of pharmaceuticals from aqueous solution.

Enhanced Hydrophobicity and Oleophilicity of Modified Activated Carbons Derived from Agro-Wastes Biomass for the Removal of Crude Oil from Aqueous Medium

Crude oil spillage has tremendous environmental impacts and poses severe pollution problems worldwide due to the continuous activities and operations in the oil and gas sector. This has resulted in the urgent need for clean-up techniques such as the use of natural adsorbents which is considered a relatively low-cost, readily-available, efficient, eco-friendly, and easy-to-deploy mode of addressing oil spillage due to its high oil sorption capacity/efficiency, high oil selectivity, oleophilic, enduring, reusability and biodegradable properties. Empty palm fruit bunch and coconut coir were used as precursors to produce activated carbons for oil spill remediation. The influence of varying parameters was investigated using a batch experimental procedure resulting in the crude oil adsorption capacity increasing with a corresponding increase in contact time, initial oil concentration, temperature, agitation speed, and particle size but decreasing in adsorbent dosage. The combination of surface morphological modification and hydrophobicity enhancement resulted in significantly improved adsorption capacity for crude oil removal (2710.0 mg/g and 4859.5 mg/g for EPFBAC<SUB>LA</SUB> and CCAC<SUB>L.A</SUB> respectively), as evidenced by both FTIR and SEM analyses. The experimental isotherm data were analysed using various isotherm models and the best-fitted isotherm model was the Freundlich model with a correlation coefficient (R<sup>2 </sup>= 0.991 and R<sup>2 </sup>= 0.999) for EPFB<SUB>L.A</SUB> and CCAC<SUB>L.A</SUB> respectively. The kinetic behaviour of the adsorption process was best described by pseudo-second order with R<sup>2</sup> values of 0.970 and 0.999 for EPFBAC<SUB>LA</SUB> and CCAC<SUB>L.A</SUB> respectively while Boyd model revealed that the adsorption was controlled by an internal transport mechanism and film diffusion was the rate-limiting step. The crude oil adsorption was chemisorption and endothermic owing to the positive enthalpy values (ΔH<sup>o</sup> = 183.890 KJ/mol for EPFBAC<SUB>L.A </SUB>and ΔH<sup>o</sup> = 69.656 KJ/mol for CCAC<SUB>L.A</SUB>), the positive value of entropy suggested that the adsorption process was accompanied by an increase in the degree of randomness or disorder at the interface between the adsorbent and the adsorbate. A temperature rise led to a decline in Gibbs energy (ΔG<sup>o</sup>), suggesting that adsorption became more feasible and spontaneous at higher temperatures and the significant activation energies indicated the existence of a substantial energy barrier that must be overcome to initiate the reaction. The results showed the significant capability of the prepared adsorbents to be used as a low-cost, re-generable and eco-friendly adsorbent in oil spill clean-up and is recommended to exploit its usage on a large scale.

Synthetic and natural antibacterial carbon adsorbents for clinical nuclear waste management

Patients undergoing high-dose radioiodine ablation (RAI) therapy in Nuclear Medicine Department need to be isolated in a special designed ward for a few days. Large amount of clinical radioactive wastewater from patient body is produced during high-activity RAI therapy. The radioactive wastewater needs to store in a delay tank until the radioactivity decayed below acceptable limit before being discharged and indirectly limit the patient admission and treatment. This study is to propose an alternative antibacterial adsorbent for I-131 extraction from clinical radioactive wastewater at the nuclear medicine department using graphene oxide silver (GOAg) and bamboo activated carbon (BAC). The synthesised adsorbents and their sediments (filtered sample) were analysed using field emission scanning electron microscopy (FESEM) for morphological analysis and analysed using X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) and X-ray diffraction (XRD). XPS spectra for C 1s adsorbents show intensity peaks at 284.45 eV (C=C) and 285.3 eV (C–C) for GOAg and its sediments, and 284.35 eV (C–C), 287.00 eV (C=O), and 290.07 eV (π–π∗ transitions) for BAC and its sediments. FTIR spectra reveal various functional groups of adsorbents: C=C (1637.50772 cm−1), C=O (1340.48041 cm−1), and C–O–C (1031.88060 cm−1) for GOAg and its sediments, and C=C (1635.57897 cm−1), C–C (1257.54421 cm−1), and C–O (1188.10925 cm−1) for BAC and its sediments. XRD patterns exhibit peaks at 2θ = 27.82°, 29.39°, 32.24°, and 46.22°, which can be attributed to the (002) diffraction plane, (220) crystallographic plane, (111) plane of Ag2O, and (200) crystallographic plane, respectively, for GOAg and its sediments. Meanwhile, the peaks at 2θ = 26.56° and 42.41°, which correspond to (002) and (100) planes, respectively, for BAC and its sediments. The d-spacing and the crystallinity index of each adsorbent were also determined. The estimation of the remaining β− particles during the adsorption of I-131 was carried out using PHITS. The finding of this study is beneficial for alternative radionuclide extractions technique from clinical radioactive wastewater in nuclear medicine.

Unveiling bisphenol A toxicity: human health impacts and sustainable treatment strategies

Abstract Introduction The widespread presence of bisphenol-A (BPA) in consumer goods like water bottles and eyeglass frames raises serious concerns about the chemical’s ability to accumulate in human tissues. Molecular filtration and activated carbon adsorption are two of the many BPA treatment technologies that have emerged in response to these issues; both are essential in the removal or degradation of BPA from water sources and industrial effluents. Content To secure the long-term health and environmental advantages of BPA treatment approaches, sustainable development is essential. Both the efficient elimination or destruction of BPA and the reduction of the treatment operations’ impact on the environment are important components of a sustainable approach. Different search engines like Pub-Med, MEDLINE, Google Scholar and Scopus are used for these systematic reviews and analyzed accordingly. This can be accomplished by making treatment facilities more energy efficient and using environmentally friendly materials. Greener ways to deal with BPA pollution are on the horizon, thanks to innovative techniques like bioremediation and improved oxidation processes. Reducing dependence on conventional, resource-intensive procedures can be achieved by investigating the use of bio-based materials and natural adsorbents in treatment processes. Summary and Outlook This review article tackling the health and environmental concerns raised by BPA calls for an integrated strategy that incorporates sustainable development principles and technology progress. We can reduce the negative impacts of BPA contamination, improve environmental stewardship in the long run, and ensure human health by combining cutting-edge treatment technologies with sustainable behaviours.

Adsorption Behavior and Mechanism of Brilliant Green Dye onto Acid-modified Mesoporous Volcanic Pumice

Water pollution is a major problem in the environment. The important one is the dying effluent from the textile industry. Dye effluent has affected human health and aquatic life. Recently, natural adsorbents have been most commonly used for dye treatment wastewater. This study explores the adsorption mechanism of brilliant green onto HCl-modified pumice. It involves a comparative analysis of the raw and HCl-modified pumice's characterization and adsorption properties. The adsorption experiments were carried out by considering several parameters, such as pH, contact time, initial dye concentrations, and temperatures. The research indicated that the raw and acid-treated pumice possess Si-OH and Si-O-Si groups. These pumice adsorbents are classified as mesoporous, exhibiting BJH pore diameters of 3.23 nm for the raw form and 3.69 nm for the acid-modified variant. The adsorption data revealed that the uptake of brilliant green dye was maximal at a pH of 8. The equilibrium results closely matched the Langmuir isotherm model. The maximum adsorption capacities were 37.13, 40.17, and 42.73 mg g-1 for the raw pumice, and 46.72, 51.81, and 56.17 mg g-1 for the modified pumice at 20, 30, and 40 °C, respectively. Furthermore, the removal efficiency of brilliant green dye with modified pumice was 91.93%, 95.29%, and 96.27% at 20°C, 30°C, and 40°C, respectively. The pseudo-second-order model was the most suitable for elucidating the kinetic adsorption data. The thermodynamic analysis revealed that the adsorption process was endothermic, spontaneous, and physical. Dipole-dipole H-bonding interaction, Yoshida H-bonding, electrostatic interaction, n-𝝅 interaction, cation exchange, and pore filling were all engaged in its process. Consequently, the local pumice volcanic rock became a great, cheap, abundant, and environmentally friendly adsorbent for removing dyes from effluents.

Kinetics, Thermodynamics, and Mechanistic Studies of Arsenic Removal Utilizing Natural Soil as Adsorbent.

The contamination of water sources with the heavy metal contaminant arsenic (As) causes substantial risks to humans, animals, and other living organisms. Therefore, the introduction of methods for the removal of As is important. The present study aimed to investigate the adsorption model and mechanism of As removal utilizing natural soil adsorbents. The batch adsorption technique was used to analyze the impacts of various parameters such as contact time, initial As concentration, pH, and temperature. Adsorption mechanisms were studied through adsorption kinetic, isotherm, and thermodynamic models. The batch adsorption study findings indicate that the optimal conditions for maximum As removal were achieved by application of 2.2 g of adsorbents in 50 μg/L of As solution for 60 min of contact time at a pH of 5.5 ± 0.5 and a temperature of 40 °C. The highest removal efficiency was achieved when red soil was employed as the adsorbent. The kinetic, isotherm, and thermodynamic models revealed that As adsorption was a chemisorptive, nonspontaneous, and endothermic process.

Effects of Over-Sintering on Cyclic Calcination and Carbonization of Natural Limestone for CO2 Capture

To know the sustainable performance of calcium-based adsorbents is one of the important aspects to realize efficient and economical carbon capture, and to systematically study the properties of natural adsorbents is conducive to their industrialization. The cyclic calcination and carbonation characteristics of a typical natural limestone were investigated using a thermal gravimetric analyzer. Two kinds of over-sintering conditions were selected to emphatically study the cyclic separation of CO2 from limestones through prolonging the calcination time and increasing the calcination temperature. The results showed that the untimely end of the chemical reaction control stage caused by excessive sintering is the direct reason for the reduction in cyclic carbonation conversion, and the changes in surface morphology of calcined products due to pore collapse and fusion are the fundamental reasons for the reduction in cyclic carbonation conversion. The excessive sintering caused by extending the calcining time or increasing the calcining temperature has great inhibition on this cycle only; the inhibition decreases rapidly in subsequent cycles. In addition, SEM and BET–BJH tests further confirm the influence of the over-sintering phenomenon. With the further increase in cycle number, the early excessive sintering has certain stimulative effects on the subsequent carbonation reaction. It is expected to provide a reference for the subsequent research and development of natural calcium-based adsorbents.

Recent Advances on the Adsorption of Pollutants from Aqueous Media Using Clay-Based Adsorbents

The sequestration of pollutants from wastewater remains an active research topic recently owing to persistent disposal of industrial wastewater to waterbodies without adequate management strategies available especially in the developing countries. Different technologies have been employed in which adsorption has found a wide range of application. Today, various low cost adsorbents have been developed and evaluated for the adsorption processes. Clay mineral is one of the low cost natural adsorbents requiring minimum modification to enhance its adsorptive capacities. To maintain a clean and safe environment the water bodies must be free of contaminants of emerging concern. The availability of potable water is a global effort, as two of the UN's seventeen Sustainable Development Goals (SDG) are centered on water which is not surprising. Goal 6 focuses on clean water and sanitation whereas Goal 14 focuses on life below the water. With this in view, the availability of potable water highlights the significance of this study, which analyzes the potential of clay minerals as a good precursor for water treatment. Therefore, this review focuses on the clay minerals, its availability in Nigeria, classification and modification of the clay adsorbent.

Adsorption performance with field emission scanning electron microscopy of fruit peel induced Silver Nanoparticles in C16H18ClN3S for waste water treatment

There is a growing demand for cost-effective and sustainable technologies for treating wastewater as water consumption increases and conventional technologies become more expensive. Nanoparticles have a great deal of potential for use in the treatment of waste water. Their unique surface area allows them to effectively remove toxic metal ions, pathogenic microorganisms, organic and inorganic solutes from water. This study investigated the potential of orange and banana peels as renewable nano adsorbents for removing dyes and dissolved organic compounds from textile wastewater. Orange and banana peels are an optimal selection due to their favourable chemical characteristics, namely the presence of cellulose, pectic, hemicellulose, and lignin. Their capacity to adsorb diverse anionic and cationic compounds on their surface-active sites is attributed to their unique functional group compositions. Silver nanoparticles are able to adsorb heavy metals due to their exceptionally low electrical and thermal resistance and surface plasmon resonance. The samples were thoroughly characterised using field emission scanning electron microscopy (FESEM), UV–Visible spectrometry, Fourier transform infrared spectroscopy (FTIR) and XRD. The nanoparticles were prepared (10 gm,50 gm,100 gm) and subsequently introduced to the wastewater sample. The optical density values were recorded at various time points. The optical density values demonstrate a decline over the course of the experiment, with a notable decrease observed over time. The results of this study provide valuable insights into the efficacy of these natural adsorbents and their potential for sustainable water purification technologies. For the purpose of this research, high performance instrumentation methods were performed as follows:•Field emission scanning electron microscopy for surface morphology studies.•Gas chromatography-mass spectrometry (GC–MS) for analytical technique that combines gas chromatography (GC) and mass spectrometry (MS) to identify unknown substances or contaminants.•Optical density values were measured for different timings of degradation.

Effect of Natural Adsorbents Addition into Fish Feed Rations on Water Parameters

In this research, the effects of zeolite, leonardite, and diatomite, added into fish feed of 40% protein value in different amounts, on water parameters were investigated. The experiment consisted of 10 groups with three replications (control (C), 2 % zeolite (Z2), 4 % zeolite (Z4), 8 % zeolite (Z8), 2 % leonardite (L2), 4 % leonardite (L4), 8 % leonardite (L8) 2 % diatomite (D2), 4 % diatomite (D4), and 8 % diatomite (D8)). In the study, feed containing 40 % crude protein was used to be within this protein value range. When the experimental groups in the study were examined individually, it was determined that similar to the results in the zeolite groups and leonardite groups, there was a decrease in the ammonia and TAN values in the water as the amount of adsorbent in the feed increased. When these results are evaluated, it is thought that the addition of adsorbent in greater amounts (e.g.,>8 %) than the amounts in this study could be significantly more effective.

Directional Freeze-Drying-Mediated Chitosan Aerogel with Ordered Structure Allowing High-Efficient Removal of Se(IV) from Wastewater.

The progress of industrialization has led to a notable elevation in selenium (Se) levels within aquatic environments, surpassing established thresholds and posing significant risks to both human health and ecological equilibrium. Chitosan (CS) exhibits considerable potential in mitigating waterborne pollutants owing to its nontoxic nature, cost-effectiveness, and the presence of abundant hydroxyl and amino functional groups along its backbone. However, its subpar mechanical and thermal stability, susceptibility to acidic dissolution, and challenges in recycling impede its widespread use in water pollution mitigation. To address the aforementioned issues, this study employs a liquid nitrogen-directed freezing process to synthesize chitosan aerogel, aiming to enhance the adsorption efficiency of Se(IV). Morphological and adsorption tests demonstrate that the compact and closely interconnected porous structure facilitates diffusion of Se(IV) into the aerogel, thereby enhancing its adsorption efficiency. The theoretical adsorption capacity of the CS aerogel for Se(IV) is 56.45 mg/g, surpassing that of numerous natural and composite adsorbents, with adsorption equilibrium achieved within 2.5 h. Moreover, the CS aerogel demonstrates substantial potential in remediating Se(IV)-contaminated wastewater and improving circulation stability. A series of characterization results demonstrate that the primary adsorption mechanism of the CS aerogel onto Se(IV) involves electrostatic interactions, complemented by hydrogen bonding between the amino and hydroxyl groups of the CS aerogel and Se(IV), thereby augmenting the adsorption efficacy. This study introduces innovative avenues for tailoring the functionality of 3D macroscopic materials to address the remediation of heavy metals in aquatic environments.

Data on vermicompost effect on the uptake of cadmium from soil by the roots of radish (Raphanus sativus)

Cadmium is a common environmental heavy metal that is very toxic and carcinogenic for human and other flora and fauna. Therefore, this study is aimed to evaluate the fisibility of vermicompost fertilizer for cadmium uptake from soil by the root of radish (Raphanus sativus). For the purpose of the study, four different ratios of one case control, 1 per 1, 1 per 4, 2 per 4, 3 per 4 vermicompost fertilizer per soil with 0, 50000 and 100000 µg/L cadmium concentrations was evaluated. Cadmium in the samples was measured using an Atomic Absorption Spectroscopy (AAS). The results showed that the minimum uptake of cadmium by the plant was observed for 3 per 4 ratio of fertilizer per soil. In addition, results revealed that highest growth rate of Raphanus sativus roots occurred in maximum ratio of fertilizer per soil usage (3 per 4). This study showed that vermicompost as a organic fertilizer has a good ability to adsorb cadmium metal from soil. Therfore, vermicompost application can be considered as an inexpensive natural adsorbent in arable land contaminated with cadmium.•Heavy metals are very toxic and carcinogenic to human and animals.•Adding organic fertilizer to the soil increases the absorption of heavy metal (cadmium) in the soil and prevents it from entering the food chain.•The relationship between the concentration of cadmium absorbed by the tuber of radish plant and the percentage of vermicompost added to the soil is presented.

Utilizing banana peduncle as an affordable bio-adsorbent for efficient removal of lead ions from water and industrial effluents

The use of efficient biobased materials for the treatment of heavy metal-contaminated wastewater has been demonstrated to be a highly effective method. The natural adsorbent banana peduncle has a lot of potential for treating wastewater because it is renewable, inexpensive, readily available, and environmentally benign. To learn more about the possible uses of these adsorbents, we synthesized them from banana peduncles and studied their shape, crystalline structure, and functional groups. The following parameters were found to be ideal for lead biosorption in batch trials concentrating on Pb (II) removal: a pH of 5, a contact period of 120 min, particle sizes between 240 and 300 mesh, concentrations at 40 mg/L, dosages of 3 g/L, and agitation rates of 200 revolutions per min (RPM). The banana peduncle showed an amazing biosorption efficiency of 94.0 % in the results. A comparison was made between the Freundlich, Langmuir, and Temkin models to investigate the adsorption isotherms of lead (II) ions. The R2 values obtained for these models were 0.9946, 0.9769, and 0.9537, respectively. Models that were pseudo-second-order and first-order were evaluated; the latter showed a better fit. The effectiveness and affordability of banana peduncle as the best adsorbent were highlighted by desorption testing. This study shows how materials made from banana peduncles can be an effective and sustainable way to reduce heavy-metal pollution in wastewater. This paper is the first to explore the potential absorption of Pb (II) by the peduncle of bananas, based on our current understanding.