Biosorbent Dosage Research Articles

Eco-Friendly Green Approach to the Biosorption of Hazardous Dyes from Aqueous Solution on Ragweed (Ambrosia artemisiifolia) Biomass

The presented research includes the preparation, characterization, and implementation of magnetic biosorbent (Fe3O4/RWB), obtained from ragweed (Ambrosia artemisiifolia) biomass. Fe3O4/RWB was examined for the removal of a hazardous dye, malachite green (MG), from an aqueous solution in a batch system. The effects of the experimental parameters—initial dye concentration (10–300 mg/L), contact time (0–120 min), biosorbent dose (1–5 g/L), initial pH (2–10), ionic strength (0–1 mol/L), and temperature (298–318 K) on dye biosorption—were studied. The results showed that increases in biosorbent dose, contact time, and initial pH led to an increase in biosorption efficiency, while the increase in initial dye concentration, the ionic strength, and temperature had the opposite effect. The biosorption kinetics for MG on Fe3O4/RWB were analyzed with pseudo-first-order, pseudo-second-order, and Elovich kinetic models, while the Langmuir, Freundlich and Temkin isotherm models were used for equilibrium data analysis. It was observed that the MG biosorption followed the pseudo-second-order kinetic model, whereas the Langmuir model was the best fit for the equilibrium biosorption data of MG, with a Qmax of 34.1 mg/g. the desorption of MG from Fe3O4/RWB indicated reusability in five adsorption/desorption cycles, good performance, and potential in practical applications.

Methylene blue adsorption by chemical-activated Trichanthera gigantea leaf

ABSTRACT This study investigated the potential of NaOH-treated Trichanthera gigantea leaf (TGL) powder as a sustainable, low-cost biosorbent for methylene blue (MB) removal from wastewater. Characterization using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller, and energy-dispersive X-ray spectroscopy (EDX) techniques confirmed favorable morphology, identifying micropores, suitable functional groups, notable surface area, pore volume, and elemental diversity. Batch experiments systematically investigated the influence of operational parameters, including contact time, initial MB concentration (5–35 mg/L), pH (2–10), and biosorbent dosage (2–10 g/L) on adsorption performance. The Langmuir isotherm model best represented the experimental data (R² values of 0.993 and 0.9725), indicating favorable adsorption (RL < 1) and maximum MB adsorption capacities of 0.822 and 0.330 mg/g for treated and untreated TGL, respectively. Statistical analysis (ANOVA) results further identified the most significant factors influencing MB biosorption. These findings highlight the potential of NaOH-treated TGL powder as an effective and eco-friendly solution for removing MB dye from industrial effluents, contributing to sustainable wastewater treatment and environmental protection.

Adsorption ability of sugar scum as industrial waste for crystal violet elimination: Experimental and advanced statistical physics modeling

Recycling solid industrial waste into useful resources is the most critical aspect of managing waste. Herein, for detoxifying poisonous crystal violet dye (CV) in aqueous media, sugar scum (SS) as an underutilized industrial discard has been tested as a promising adsorbent.The SS was thoroughly analyzed beforehand and after the adsorption process through various characterization techniques. Several operational factors, including pH, biosorbent dosage, dye concentration, and temperature, were optimized, reaching 24 mg.g-1 at (pH 10, 2 g.L−1 of SS, 10 mg.L−1 of CV and 25 °C). The bioadsorbent's performance was assessed through a range of studies involving kinetic, equilibrium (using both conventional and statistical physics models), and thermodynamic investigations.Based on the results, the equilibrium curves best fit the Freundlich model, indicating that multilayer adsorption occurs on a heterogeneous active sites surface. The statistical physics models provided detailed physiochemical insights, the double-layer with two energies model was most accurately describing the data, with a high saturation capability of 371 mg.g−1. Most interactions occur at a single adsorption site (70 %), with the remaining 30 % at two sites, involving both parallel and non-parallel orientations. The mesoporous structure of the SS surface provides an optimum size for CV adsorption. Pore filling, Van der Waals forces, hydrogen bonding, π-π and electrostatic interactions are proposed as the possible mechanisms in the CV-SS system. Thermodynamic measurements indicate that CV adsorption is spontaneous (ΔG° < 0) and exothermic ΔH° (− 41.390 kJ mol−1).The SS recyclability was assessed, exhibiting encouraging sustainability with a slight fall in effectiveness (∼7 %) after 5 sequential usages. Altogether, this study makes a substantial contribution to the promotion of ecological water treatment strategies, which highlights the utility of using SS as an environmental alternative to water contaminant remediation.

Biosorption of methylene blue by bone meal: experimental and modeling with machine learning and full factorial design

Sorption technologies have been proposed for the treatment of water containing methylene blue (MB), a toxic and persistent pollutant. Despite its environmental risks, the role of process variables in MB removal has not been fully explored through experimental design. The objective of this study is to assess the potential of bone meal powder (BMP), an underexplored agricultural byproduct, as an affordable adsorbent for the removal of MB from water. BMP was subjected to a series of analytical characterization techniques, and its adsorption capacity was evaluated through a comprehensive factorial design, which investigated the effects of biosorbent dosage, solution pH, and initial MB concentration. The study revealed that the highest adsorption level was 14.49 mg g−1, attained under the following conditions: 1 g L−1 BMP, pH 11, and 100 mg L−1 MB. The adsorption equilibrium was reached within 60 min, with a measured capacity (qexp) of 18 mg g−1. Theoretical adsorption isotherms indicated a capacity of 63 mg g−1, which aligned well with the Langmuir model. To predict adsorption outcomes, machine learning models were applied, with multiple linear regression performing best. Optimization of decision trees and neural networks improved accuracy but risked overfitting. FT-IR, XRD, and ICP analyses indicated ion exchange as a significant mechanism of adsorption. In desorption studies, H2SO4 was the most effective agent, achieving 68.72% desorption efficiency. BMP exhibited optimal recyclability for up to four cycles before efficiency declined.

Application of Marine Mollusk Shells (Meretrix lusoria) as Low-Cost Biosorbent for Removing Cd2+ and Pb2+ Ions from Aqueous Solution: Kinetic and Equilibrium Study

The present work aims to evaluate the applicability of mollusk (Meretrix lusoria) shells as a biosorbent for toxic metal ions (Cd2+ and Pb2+) following the batch mode biosorption procedure. Some well-known analytical methods have been used to characterize the biosorbent such as a scanning electron microscope (SEM), an energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction. The mechanism of metal ion biosorption was examined using various analytical techniques. Therefore, an evaluation of operating factors such as contact time, pH, initial concentration of metal ions, biosorbent dose, and temperature was performed. The results obtained in this investigation indicated that the optimum conditions for the biosorption of Cd+2 and Pb+2 ions are as follows: pH = 6; contact times of 90 min; and the 20 mg/L of initial [M2+]. And a biosorbent dosage of 1.0 g/100 mL for each metal ion solution was also determined. The maximum removal efficiency results were 90.6% for Cd+2 and 91.5% for Pb+2 at pH 6.0. The biosorption isotherm was investigated using three forms of linear equilibrium (Freundlich, Langmuir, and Temkin models). Kinetic studies were also conducted to determine the equilibrium time for the biosorption of the studied metals utilizing the pseudo-second-order, pseudo-first-order, and intraparticle diffusion model. The data indicate that the biosorption kinetics of Cd2+ and Pb2+ follow the pseudo-second-order models. According to the present study, it can be identified that the shell of Meretrix lusoria is a suitable biosorbent for Cd2+ and Pb2+ ions and can contribute to their removal from environmentally polluted water.

Cost-effective walnut shell biosorbent for efficient Cr(VI) removal from water: Batch adsorption and optimization using RSM-BBD

The conversion or recycling of waste materials into usable products is a sustainable and ecologically benign strategy, aligning with sustainable development and circular economy principles. This study presents a straightforward and cost-effective method for transforming walnut shells, commonly found in agricultural waste, into a biosorbent material highly effective in eliminating hexavalent chromium (Cr(VI)) from water. The prepared material underwent several analyses to determine its physical characteristics and surface chemistry, revealing an amorphous structure similar to lignocellulosic materials. Using Response Surface Methodology (RSM-BBD), we accurately forecasted and optimized the Cr(VI) adsorption process, evaluating and enhancing factors such as pH, biosorbent dosage, pollutant concentration, and adsorption time. Significant enhancement in the removal percentage (%R) was achieved, reaching 100 % after optimization. The RSM-BBD model provided high-quality prediction for data fitting (R² = 0.999). Various kinetic models, including PFO, PSO, and IPD models, were employed, with the PSO model providing the best depiction of adsorption. Equilibrium data analysis using the Langmuir, Freundlich, Redlich-Peterson and Temkin models revealed that the Freundlich model and R-P better fit the adsorption isotherm of Cr(VI) on treated walnut shell (WST). Furthermore, examination of Gibbs free energy and enthalpy indicated that the adsorption of Cr(VI) onto walnut shells is a spontaneous and exothermic reaction, resulting in the release of thermal energy.

Studies on the equilibrium, thermodynamics, and kinetics of the biosorption of copper (II) and lead (II) onto Indian willow (Salix tetrasperma) leaves

ABSTRACT Potentially toxic metals in water threaten humans, animals, and the environment. The potential of Indian willow (Salix tetrasperma) leaves to biosorb copper and lead from water was examined. Utilising scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and Fourier transform infrared spectroscopy (FTIR) spectrum analysis, the properties of Salix tetrasperma biomass (STB) was investigated. The maximum removal percentage (92.8% for copper and 89.9% for lead) was achieved at pH 5.0, a biosorbent dosage of 3.0 g/L at 25°C, and a 10 mg/L initial concentration of copper and lead. The determination of the point zero charge (pHzpc = 5.0) indicated the prevalence of a negative charge on the surface of the biosorbents. The kinetic equation utilised in the pseudo-second-order model effectively. Langmuir isotherm better described experimented data than the Freundlich model. The Dubinin-Radushkevich isotherm provided a good fit for the study's equilibrium data. STB recorded an adsorption capacity, Qmax, of 43.99 mg/g for copper (II) and 39.66 mg/g for lead (II) ions at an optimum pH of 5. Thermodynamically, the biosorption of both ions on STB was spontaneous, endothermic, and feasible. The selected modified STB was found to be suitable for adsorbing copper (II) and lead (II) metal ions.

Correction: Abatal et al. Comparison of Heavy Metals Removal from Aqueous Solution by Moringa oleifera Leaves and Seeds. Coatings 2021, 11, 508

The main goal of the work was to study the Moringa oleifera leaves and seeds as sorbents against Pb(II), Cd(II), Co(II), and Ni(II) from aqueous solutions, to explore the effect of various parameters (such as contact time, biosorbent dosage, and initial concentration of metals) and to determine the adsorption mechanisms [...]

Sorption of chromium from aqueous solutions using Fucus vesiculosus algae biosorbent

The presence of heavy metals in wastewater is an environmental concern and the current treatment procedures are very expensive so it is necessary to find effective and inexpensive biosorbents. In this study, Fucus vesiculosus was used as a biosorbent for the biosorption of Cr(III) ions from the aqueous solutions. Biosorption parameters, such as pH, adsorbent dose, contact time, and initial concentrations of Cr(III) had the most impact on the sorption process. The required pH value for sorption was 5, the biosorbent dose was 4.0 g/L, the contact time was seen to occur after 90 min, and the Cr(III) removal decreased from 98.9 to 92%. The maximum biosorption capacity of chromium was 14.12 mg/g. FTIR analysis of Fucus vesiculosus biomass before the sorption process contains carboxyl, amino, hydroxyl, alkyne, and carbonyl groups, and according to the analysis after the sorption process, it was found that Cr(III) metal ions were incorporated within the sorbent during the interaction with (=C–H) active functional groups. The biosorption data were found to be perfectly suited by Langmuir equilibrium isotherm model. According to the results of this study, Fucus vesiculosus is an effective biosorbent for the removal of Cr(III) from aqueous solutions.

Biosorption of reactive amoxicillin antibiotic on Pithophora macroalgae in aqueous solution: Equilibrium and kinetic studies

The removal of antibiotics is a significant environmental concern due to their complex structure. Therefore, scientists are working on novel and efficient techniques for removing antibiotic compounds from aqueous solutions. The current research aims to utilize green Pithophora macroalgae for extracting the antibiotic amoxicillin (AMX). An investigation into the kinetics and equilibrium mechanism of the biosorption of reactive AMX on macroalgae biomass in aqueous solutions has been conducted. The effects of operating factors such as initial AMX concentration, contact time, biosorbent dosage, agitation speed, and pH were investigated. FT-IR, SEM, and point of zero charge pH (PZC) techniques were used to characterize the biosorbent. The Langmuir and Freundlich isotherms were examined to determine which model better fits the experimental data. The experimental data best matches the Langmuir isotherm model for AMX biosorption, with a maximum sorption capacity of 25.83 mg g-1. The kinetic model for the experimental results follows the pseudo-second order (R2 = 0.9992). According to this study, the biomass of the macroalgae Pithophora has been shown to be a promising biosorbent for the biosorption of AMX antibiotics, making it suitable for practical water and wastewater treatment applications.

Experimental investigation of Cd (II) ion adsorption on surface-modified mixed seaweed Biosorbent: A study on analytical interpretation and thermodynamics

Despite advancements in wastewater treatment technologies, heavy metal contamination, especially cadmium (Cd), severely threatens human health and ecosystems. The purpose of this work is to compare the removal of Cd (II) ions from aqueous solutions by chemically modified mixed seaweed biosorbent (CMSB) and physically modified mixed seaweed biosorbent (PMSB). BET, SEM, EDAX, FTIR, and XRD techniques characterized the mixed seaweed biosorbents before and after adsorption. They are well-known for their sustainability, affordability, and biodegradability. The BET study revealed that CMSB had a surface area of 19.682 m2/g, while PMSB had a lower surface area of 14.803 m2/g. The optimum adsorption conditions were a temperature of 303 K, pH of 6.0, and biosorbent dosages of 1 g/L for CMSB and 2.5 g/L for PMSB. For CMSB and PMSB, the most efficient contact times were 40 and 80 min, respectively. The Langmuir model was demonstrated to be the best fit for the experimental data when compared to other isotherm models, with a coefficient of determination, or R2, of 0.9713 and a maximum monolayer capacity of 151.2 mg/g and 181.6 mg/g for physical and chemical activated mixed seaweed biomass. There was a significant relationship between the R2 values of chemically modified and physically modified biomass. The findings demonstrate that pseudo-second-order kinetics more accurately represent the adsorption process than pseudo-first-order and Elovich models. Thermodynamic experiments validated the endothermic, spontaneous and favourable characteristics of the removal process. According to the results of the current study, PMSB and CMSB may be used as effective adsorbents to remove Cd (II) from aqueous solutions.

Green Synthesis of MgO Nano Particle Loaded Onto Carbon for Effective Rhodamine B Dye Removal

ABSTRACTIn this study, Rhodamine B dye (RhB) is effectively removed from aqueous solutions by using nano‐MgO and nano‐MgO activated carbon as an adsorbent. First, potassium hydroxide was used in a chemical activation process to create activated carbon from the Anacardium occidentale shell, often known as the cashew nutshell. Rosa cymose extract was used in a quick precipitation process to create nano‐magnesium oxide in a sustainable way. Activated carbon composite impregnated with nano‐magnesium oxide was made using a dropwise process. The study examined the nanocomposite that removed the dye Rhodamine B from the aqueous solution. Using SEM, XRD, FTIR, and EDX, the nano‐Mgo and nano‐MgO‐AC were analyzed. Using a scanning electron microscope, an analysis was conducted on the evenly distributed accumulation of MgO nanoparticles added to the activated carbon. The capability of nano‐MgO‐activated carbon to decolorize RhB was investigated. The effects of beginning pH ranges of 2.0–9.0, initial dye concentrations of 10–40 ppm, biosorbent dosages of 0.2–1.2 g, and contact times ranging from 10 to 60 min were investigated. At pH 5, most dye was eliminated. The work has shown that RhB may be effectively removed from aqueous medium using nano‐MgO‐AC, it could potentially be used as an affordable adsorbent material. Equilibrium estimations were acknowledged strongly through Langmuir approximations with a correlation determination of 0.985.

Enteromorpha compressa Macroalgal Biomass Nanoparticles as Eco-Friendly Biosorbents for the Efficient Removal of Harmful Metals from Aqueous Solutions

This study focuses on the biosorption of harmful metals from aqueous solutions using Enteromorpha compressa macroalgal biomass nanoparticles as the biosorbent. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction analysis (XRD) were employed to characterize the biosorbent. The effects of pH, initial metal ion concentration, biosorbent dosage, and contact time on the biosorption process were investigated. The maximum biosorption capacity for metals was observed at a pH of 5.0. The experimental equilibrium data were analyzed using three-parameter isotherm models, namely Freundlich, Temkin, and Langmuir equations, which provided better fits for the equilibrium data. A contact time of approximately 120 min was required to achieve biosorption equilibrium for various initial metal concentrations. Cr(III), Co(II), Ni(II), Cu(II), and Cd(II) demonstrated distinct maximum biosorption capacities of 24.99375 mg/g, 25.06894 mg/g, 24.55796 mg/g, 24.97502 mg/g, and 25.3936 mg/g, respectively. Different kinetic models were applied to fit the kinetic data, including intraparticle diffusion, pseudo-second-order, and pseudo-first-order versions. The pseudo-second-order model showed good agreement with the experimental results, indicating its suitability for describing the kinetics of the biosorption process. Based on these findings, it can be stated that E. compressa nanoparticle demonstrates potential as an effective biosorbent for removing targeted metals from water.

Sustainable Processes of Biosorption of Pb(II) Ions from Synthetic Wastewater Using Waste Biomass from Mullein Leaves

The aim of this study is to evaluate mullein (Verbascum thapsus) as a cost-effective and sustainable adsorbent for the biosorption of Pb(II) ions from synthetic wastewater samples. Biosorption of mullein was investigated as a function of initial Pb(II) concentration (25–400 mg L−1), biosorbent dosage (2–20 g L−1), solution pH (3–7), and contact time (10–120 min). Mullein as a material with a high affinity for Pb(II) ions had a biosorption efficiency of 98.56% under the optimal conditions: pH 6, initial concentration of Pb(II) at 100 mg L−1, contact time of 90 min, and biosorbent dosage of 20 g L−1. The FTIR spectra of mullein leaves showed that oxygen-containing functional groups on the surface are potentially active sites for the biosorption of Pb(II) ions. EDS analysis and the pHPZC value confirmed the adsorption of Pb(II) ions at the active sites of the mullein. Kinetic and isotherm data enabled insights into the modes of Pb(II) biosorption on the mullein surface which were best explained with the pseudo-second-order kinetic model and the Freundlich adsorption isotherm. Biosorption occurs on the mullein surface via multilayer adsorption. The reusability of mullein showed that the native biosorbents can be reused five times, showing the economic and sustainable benefit of this low-cost biosorbent material.

Sustainable removal of methylene blue dye from textile effluents by magnetized Tea waste and Peanut shells

Methylene blue finds numerous applications across various industries but its prolonged exposure to living organisms can result in significant health risks. In this study, the adsorption of magnetized Peanut shells and Tea waste for methylene blue dye removal has been reported. The biosorbents were synthesized by co-precipitation method and their suitability for methylene blue adsorption was confirmed through characterization techniques including Scanning Electron Microscope, Fourier Transfer Infrared Spectroscopy and X-Ray Diffraction analysis. After optimizing for pH (8.0), temperature (312 k), biosorbents dosage 25 mg/L with contact periods (35 min for Tea waste@Fe3O4 and 40 min for Peanut shells@Fe3O4), and initial methylene blue concentrations (5 ppm), the removal percentages of 95.88 % for Tea waste@Fe3O4 and 84.11 % for Peanut shells@Fe3O4 were achieved effectively. The equilibrium data for MB dye adsorption fitted well with the Langmuir model (R2 = 0.99) for Tea waste@Fe3O4 which indicated the formation of monolayer formation of adsorbate at the surface of adsorbent and the Freundlich model (R2 = 0.98) for Peanut shells@Fe3O4 confirmed the multilayers formation of MB dye at the material surface. Kinetic studies specified that both Tea waste@Fe3O4 (R2 = 0.99) and Peanut shells@Fe3O4 (R2 = 0.99) followed the pseudo-second order. Thermodynamic analysis showed that the adsorption process on Tea waste@Fe3O4 and Peanut shells@Fe3O4 was spontaneous (−ΔG) and endothermic. Tea waste@Fe3O4 exhibited ΔH (27.97 kJ/mol) and entropy ΔS (93.69 kJ/mol) while ΔH = 208.9 kJ/mol and ΔS 62 kJ/mol were found for Peanut shells@Fe3O4. The performance of the proposed biosorbent in industrial effluent demonstrated their effectiveness, highlighting their potential as a cost effective and sustainable solution for wastewater treatment.

Biocomposite Material Based on Lactococcus lactis sp. Immobilized in Natural Polymer Matrix for Pharmaceutical Removal from Aqueous Media.

Ecosystems are negatively impacted by pharmaceutical-contaminated water in different ways. In this work, a new biosorbent obtained by immobilizing Lactococcus lactis in a calcium alginate matrix was developed for the removal of pharmaceuticals from aqueous solutions. Ethacridine lactate (EL) was selected as the target drug. Lactococcus Lactis biomass was chosen for the biosorbent synthesis for two reasons: (i) the microbial biomass used in the food industry allows the development of a low-cost biosorbent from available and renewable materials, and (ii) there is no literature mentioning the use of Lactococcus Lactis biomass immobilized in natural polymers as a biosorbent for the removal of pharmaceuticals. The characterization of the synthesized biosorbent named 5% LLA was performed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis. Additionally, particle size and the point of zero charge were established. Batch biosorption investigations showed that using 5% LLA at an initial pH of 3.0 and a biosorbent dose of 2 g/L resulted in up to 80% EL removal efficiency for all EL initial concentrations (20-60 mg/L). Four equilibrium isotherms, given in the order of Redlich-Peterson > Freundlich > Hill > Temkin, are particularly relevant for describing the experimental data for EL biosorption on the 5% LLA biosorbent using correlation coefficient values. Kinetic parameters were determined using kinetic models such as pseudo-first-order, pseudo-second-order, Elovich, Avrami and Weber-Morris. The pseudo-second-order kinetics model provides the greatest fit among the evaluated equations, with correlation coefficients greater than 0.99. According to the study's findings, the developed biocomposite is a potentially useful material for the removal of pharmaceuticals from aqueous matrices.

Thermodynamic, kinetic, and equilibrium studies of Cu(II), Cd(II), Ni(II), and Pb(II) ion biosorption onto treated Ageratum conyzoid biomass

The issue of environmental contamination, particularly caused by the existence of heavy metal particles, is a major and widely recognized subject that receives substantial global attention. The remediation of Cu(II), Cd(II), Ni(II), and Pb(II) ionic metal particles from synthetic wastewater using chemically treated plant leaves of Ageratum conyzoides (TAC) as a biosorbent was investigated. The biosorption process was implemented utilizing a batch system, wherein several operational parameters were considered, including temperature, pH, agitation time, biosorbent dosage, and initial concentration of the metal ion. Langmuir, Freundlich, Temkin, and D-R isotherm models were used to evaluate equilibrium data. The analyzed parameter exhibits characteristics that were best fitted with the Langmuir isotherm. The observed biosorption capacities (qm) of Cu(II), Pb(II), Ni(II), and Cd(II) ions on the TAC were measured as 51.573, 30.49, 33.53, and 35.91 mg/g, respectively, at a temperature of 22 °C. The affinity sequence of these metal ions follows the order Cu(II) > Pb(II) > Ni(II) > Cd(II). The measured values for the biosorption free energy change (ΔG) of Cu(II), Pb(II), Cd(II), and Ni(II) metal ions ranged from −1.017 to −4.723, −1.368 to −3.612, −2.785 to −5.21, and −1.047 to −5.135 kJ/mol, respectively. The enthalpy (ΔH) for Cu(II), Pb(II), Cd(II), and Ni(II) were determined to be +19.33, +6.82, +14.83, and +38.07 kJ/mol, respectively. Similarly, the corresponding entropy changes (ΔS) for the same series of metal ions were recorded as +0.075, +0.064, +0.063, and +0.135 kJ/mol.K. The pseudo-second-order kinetic models yielded superior outcomes in comparison to the pseudo-first-order kinetic models. The findings of the experiment indicated that the TAC demonstrates favorable efficacy in extracting all four metal ions. Hence, the utilization of biomass derived from Ageratum conyzoides leaves has proven to be a viable and economically feasible approach for biosorption of all four metals.

An experimental study on the parthenium biosorbents for removals of chlorides and hardness from contaminated water

Among the problems most severe for the environment is the pollution of aqueous solution, specifically the creation of threats connected to hazardous heavy metals. In some rural places, it is hardness and chlorides that make groundwater or surface water dangerous in terms of the level of toxins. The requirement of hardness and chlorides is influenced because, in large quantities, when it comes to the quality of drinking water, it causes disease. Water is hazardous to the eyes because of its alkaline nature, inhalation organs, and skin problems. The more hardness and chlorides and related irritations there are, the larger the share. A naturally occurring physiochemical mechanism called biosorption enables certain biomass to passively adsorb hardness and chlorides into the biomass's cellular structure. In the lab, five distinct biosorbents were created, including parthenium, rice husk, rapeseed straw, sawdust, and egg cells, in that order. The parthenium biosorbents turned out to be the most successful biosorbents, despite the fact that each biosorbents has a different level of effectiveness in eliminating hardness and chlorides from water. By using the plant based biomass of parthenium, 65 % of chloride removal with 80 % of hardness removal was obtained. Having identified the best biosorbents, we optimized their parameters and took water samples from different sources. In chlorides removal over parthenium biosorbents, the optima dosage of biosorbents is 3.8 g, temperature is 35 °C, pH is 7, contact time is 120 min and optima agitation speed is 120 rpm. In hardness removal over parthenium biosorbents, the optima dosage of biosorbent is 5.4 g, temperature is 35 °C, pH is 6.5, contact time is 90 min and agitation speed is 150 rpm. Once the chlorides and hardness ions are removed from the water by the utilized biosorbents, the biosorption process may be homo cost effective through the regeneration and reuse of the biosorbent.

A versatile study of single and binary removals of Pb(II) and Cd(II) ions from aqueous solutions using pine cone as biosorbent

A naturally occurring biosorbent (pine cone) was utilized to remove single and binary Pb(II) and Cd(II) ions from aqueous solutions. The biosorbent has been examined using ATR-IR, SEM, XRD, and pHpzc. The impacts of process factors such as contact time, pH value, biosorbent dosage, initial concentration, and medium temperature on the biosorption of Pb(II) and Cd(II) ions were researched. Langmuir and Freundlich's isotherms were implemented to describe the equilibrium process. At the most favorable condition for each metal, the Langmuir isotherm yielded a maximum loading capacity (qmax) of 43.47 mg/g for Pb(II) and 32.89 mg/g for Cd(II). The highest biosorption was reached with a single system and then reduced in the presence of coexisting ions in the mixtures under optimal conditions. Desorption studies show that 0.5 M HNO3 is the most effective way to remove heavy metals from a biosorbent loaded with metal ions. Thermodynamic parameters (ΔH°, ΔS°, and ΔG°) calculated from temperature data indicate that the biosorption mechanism is exothermic for Pb(II) and endothermic for Cd(II), spontaneous and favorable.

Sequestration of an Azo Dye by a Potential Biosorbent: Characterization of Biosorbent, Adsorption Isotherm and Adsorption Kinetic Studies.

This study explores the detailed characterization of a biosorbent (Hen Feather) and its efficient use in eradicating the azo dye Metanil Yellow (MY) from its aqueous solutions. Effects of a range of experimental parameters, including pH, initial dye concentration, biosorbent dosage and contact time on the adsorption, were studied. A detailed physical and chemical characterization of the biosorbent was made using SEM, XRD, XPS and FTIR. During the optimization of adsorption parameters, the highest dye uptake of almost 99% was recorded at pH 2, dye concentration 2 × 10-5 M, 0.05 g of biosorbent and a contact period of 75 min. Various adsorption isotherm models were studied to gather different adsorption and thermodynamic parameters. The linearity of the Langmuir, Freundlich and D-R adsorption isotherms indicate homogeneous, multilayer chemisorption with high adsorption affinity between the dye and biosorbent. Values of the changes in the Gibbs free energy (ΔG°) and the enthalpy (ΔH°) of the adsorption process have been calculated, these values indicate that it is a spontaneous and endothermic process. Kinetics of the adsorption were also measured, and it was established that the adsorption of MY over Hen Feather follows a pseudo-second-order kinetic model at temperatures 30, 40 and 50 °C. The findings of this investigation clearly indicate that the studied biosorbent exhibits a high affinity towards the dye (MY), and it can be effectively, economically and efficiently used to sequestrate and eradicate MY from its aqueous solutions.