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Mycotoxins are a major threat to animal and human health, as well as to the global feed supply chain. Among them, aflatoxins, fumonisins, zearalenone, T-2 toxins, deoxynivalenol, and Alternaria toxins are the most common mycotoxins found in animal feed, with genotoxic, cytotoxic, carcinogenic, and mutagenic effects that concern the animal industry. The chronic negative effects of mycotoxins on animal health and production and the negative economic impact on the livestock industry make it crucial to develop and implement solutions to mitigate mycotoxins. In this review, we summarize the current knowledge of the mycotoxicosis effect in livestock animals as a result of their contaminated diet. In addition, we discuss the potential of five promising phytogenics (curcumin, silymarin, grape pomace, olive pomace, and orange peel extracts) with demonstrated positive effects on animal performance and health, to present them as potential anti-mycotoxin solutions. We describe the composition and the main promising characteristics of these bioactive compounds that can exert beneficial effects on animal health and performance, and how these phytogenic feed additives can help to alleviate mycotoxins' deleterious effects. [ABSTRACT FROM AUTHOR]

Human and industrial activities pollute water resources with sulphur metal, endangering human health and ecosystems. Chemical precipitation and membrane filtration are expensive when treating large amounts of water, inefficient at low metal concentrations, and produce large amounts of toxic sludge and other products that must be disposed of waste water bio-sorption is eco-friendly and alternative. These methods are cheaper, more accessible, and reusable than conventional ones. This study investigates the bio-sorption of sulphur from contaminated water using neem leaf, custard apple leaf, mango tree leaf, orange peels, and banana peels biological waste materials. This work achieves 100 % removal efficiency. Biosorbents remove sulphates from contaminated water: custard leaves 100 % at 4gm, orange peels 40 % at 5gm, tea waste 50 % at 4gm, neem leaves 70 % at 5gm, and mango leaves 75 % at 5gm. The performances of biosorbents for removals of sulphates from water as follows: Custard leaves waste > Mango leaves > Neem leaves > Tea trash > Orange peels the sulphate reduction by biosorbents. The best biosorption occurred at basic pH 6.5, 3.7gm dosage, 90 min contact duration, 30 °C temperature, and 120 rpm agitation speed. The effects of contact time, agitation speed, adsorbent dosage, pH, and temperature are also examined. Before usage, biosorbents materials can be physically and chemically measured the changes. Regenerating and reusing bio-sorbent after sulphates removals makes the method cost-effective for removals of pollutants from water.

Herein, the application of granular activated carbon, jujube, and barberry tree stem powder for the removal of gasoline and kerosene from water was investigated. Kerosene removal rates upwards of 68.48, 83.87, and 99.02% were achieved using jujube tree stem powder, barberry tree stem powder, and granular activated carbon, respectively. Besides, gasoline removal rates upwards of 69.35, 55.02, and 95.59% were attained using jujube tree stem powder, barberry tree stem powder, and granular activated carbon, respectively. Isotherm data were further investigated and fitted using Langmuir, Freundlich, and Elovich models. The results indicated that the adsorption onto jujube adsorbent is a multilayer adsorption process over a heterogeneous surface, which is best illustrated by the Temkin (Ave. R2= 0.95) model. It was found that the Temkin isotherm (Ave. R2= 0.81) best describes the properties of barberry stem powder in the adsorption of gasoline and kerosene from water. Moreover, the best models to describe the characteristics of granular activated carbon in the adsorption of gasoline and kerosene from water were Freundlich (Ave. R2= 0.74) and Langmuir (Ave. R2= 0.73) isotherms, respectively. The adsorption kinetics showed that the pseudo-second-order was appropriate in modeling the adsorption kinetics of gasoline and kerosene to the studied adsorbents (R2>0.74). The objective of this study was to identify the potential of agricultural biowastes derived biosorbents to remove petroleum products from contaminated water. Previously, jujube and barberry tree wastes had not been used to remove petroleum pollutants. Moreover, in this research agricultural wastes were used without any processing or energy consumption and all experiments were performed at water pH, so there was no need to add chemicals to adjust the pH. [ABSTRACT FROM AUTHOR]

An appropriate exploitation of biosorbents for the adsorptive removal of toxic heavy metal ions has gained huge interest among the researchers due to concerns on adverse impact by chemical methods and its generation of harmful sludge as byproduct. In the present study, the efficacy of a grafted biosorbent prepared using Tamarindus indica seed gum was ascertained for removing Cr(VI) from both synthetic solution and real tannery effluent. The adsorptive performance of Cr(VI) was optimized for microwave power, exposure time, methylmethacrylate concentration, and adsorbent dosage. Further, a sample of the adsorbent was subjected to characterization using TGA, FTIR, SEM, and XRD investigations. The acquired grafter polymeric material having the highest grafting ratio and grafting efficiency was employed to optimize Cr(VI) adsorption. The results showed that the highest adsorptive removal of Cr(VI) occurred at an initial pH of the solution, 1.0, which showed the pH dependent of the process. The findings explicated that the Cr(VI) sorption by grafted copolymer biosorbent followed both the Freundlich and Langmuir isotherms, suggesting that the absorbing active sites on the biosorbent's surface were heterogeneous and that several mechanisms at work were adopted. Kinetic analysis indicated that the second-order mechanism was found to be the best fit. In addition, actual industrial effluent from tanneries was investigated for the removal of Cr(VI) using the acquired adsorbent. Furthermore, the adsorbed chromium was removed by desorption using NaOH and the reusability of the binding capacity was assessed with different cycles. [ABSTRACT FROM AUTHOR]

Sugarcane has primarily been used for sugar and ethanol production. It creates large quantities of residual lignocellulosic biomass such as sugarcane bagasse, leaves, tops, and vinasse. Biomass is a sustainable prospect for biorefineries aiming to optimize production processes. We detail recent research developments in recycling sugarcane, including energy generation and pyrolysis to obtain biofuels, for example. To produce biochar, the energy cost of operating at high temperatures and large-scale production remain as obstacles. The energy generation prospects can be enhanced by pellet production; however, it requires an improvement in quality control for long-term storage or long-distance transportation. In civil construction, the materials still need to prove their long-term efficiency and reliability. Related to adsorbent materials, the use of sugarcane bagasse has the advantage of being low-cost and environmentally friendly. Nevertheless, the extraction, functionalization, and modification of cellulose fibers, to improve their adsorption properties or even mode of operation, still challenges. The synthesis of nanostructures is still lacking high yields and the ability to scale up. Finally, controlling dispersion and orientation and avoiding fiber agglomeration could improve the mechanical response of composites using sugarcane bagasse. The different possibilities for using sugarcane and its residues reinforce the importance of this material for the industry and the global economy. Thus, the present work addresses current challenges and perspectives of different industrial processes involving sugarcane aiming to support future research on waste-derived subjects. [ABSTRACT FROM AUTHOR]

The focus on sustainable utilization of agricultural waste is currently a leading area of scientific research, driving significant advancements in technology and circular economy models. The fundamental capacity of bio-based products, bioprocessing techniques, and the crucial involvement of microbial treatments are opening opportunities for efficient solutions in various industries. One of the most popular green vegetables, peas are members of the Fabaceae family and have a pod-like structure. Every year, a significant amount of pea pods is discarded as waste products of peas that have negative impacts on our environment. In this comprehensive review, we explore innovative methods for utilizing pea pods to minimize their environmental footprint and optimize their viability across multiple industries. A large portion of the pea processing industry's output consists of pea pods. Variety of proteins, with major classes being globulin and albumin (13%), dietary fiber (43–58%), and minerals are abundant in these pods. Because of their diverse physiochemical properties, they find applications in many diverse fields. The porous pea pods comprised cellulose (61.35%) and lignin (22.12%), which could make them superior adsorbents. The components of these byproducts possess valuable attributes that make them applicable across treatment of wastewater, production of biofuels, synthesis of biocolors, development of nutraceuticals, functional foods, and enzymes for the textile industry, modification of oil, and inhibition of steel corrosion.

In recent years, numerous studies have emerged on the application of biosorbents for dyes removal from wastewater. Chitosan, a derivative of chitin, is particularly effective as a flocculant for this purpose. In this study, purified chitin was subjected to a physicochemical evaluation based on FESEM, FTIR, XRD, and TGA as well as the deacetylation step. The unique characteristics of chitin isolated using NADES enhance its suitability for efficient deacetylation and higher conversion to chitosan compared to chitin isolated with organic solvents. The chitin 1D, isolated using organic solvent, displayed a complex, convex structure, like a honeycomb, whereas chitin isolated using NADES exhibited a more fibrous and irregular structure. The data indicated that chitin extracted from BSF pupae was α-chitin with FTIR spectra matching closely to commercial chitin. Chitin isolated using organic solvent demonstrated higher crystallinity and higher thermal stability than chitin isolated using NADES. The trends of decreasing acetylation and increasing deacetylation obtained in all studied samples were indicators for the successfulness of the deacetylation reaction. The X-ray diffraction profiles verified the presence of α-chitin and the relative crystalline indexes ranged from 80 to 86 %. This study provides a green and facile approach for chitin extraction from BSF pupae using a more sustainable approach as the physicochemical properties obtained for chitin isolated using NADES are comparable with chitin isolated with the organic solvent. Multiple analytical methods employed in this study successfully demonstrated that chitin can be effectively extracted from BSF pupae, with data comparable to those published in the literature and to commercial samples.

The synthesized biochars derived from sawdust (SD) SD ozone (SDO) biochar, purified SD (PSD) biochar, and sonicated SD (SSD) biochar, which was employed in the confiscation of methylene blue (MB) dye ion, were characterized employing "Brunauer–Emmett–Teller (BET), scanning electron microscope (SEM), Fourier Transform Infrared (FTIR), and Thermal gravimetrical analysis (TGA)." The impact of various factors, such as pH, biochar dosage, and initial concentration, on MB dye sequestration, was tested in this study. It was found that the biosorption of MB dye to the various biochars was dependent on the solution pH, with optimum confiscation of MB observed at pH 12 for all biochars. Pseudo-second-order (PSO), Freundlich (FRH)- (SDO and SSD biochars), and Langmuir (LNR)- (PSD biochar) models were used to best describe the biosorption process of MB dye to various biochars. Based on the LNR model fitting to the experimental data, the optimum sorption capacities obtained using SDO, SSD, and PSD biochars were 200, 526, and 769 mg/g, respectively. Electrostatic interaction and hydrogen bonding played an important role in the interaction mechanism between the various biochars and MB dye. Hence, these studied SDO, PSD, and SSD biochars prepared from cheap, easily accessible, biodegradable, and non-hazardous agro-waste materials can be effectively used for the removal, treatment, and management of MB dye as well as other industrial effluents before their disposal into the environment. [ABSTRACT FROM AUTHOR]

The removal of pharmaceutically active compounds present in relatively low concentration in wastewater is critical. This is because they have a severe, negative impact on life and the environment. To address this issue, adsorption was used, which is an effective wastewater treatment method for removing substances found in low concentrations in water. This study compared the adsorption performance of active carbon to three biosorbents derived from Adansonia digitata shells. The adsorbents were prepared and characterized using TGA, SEM, EDX, and FTIR analyses and pHPZC. To better understand the adsorption process, equilibrium and reaction kinetics studies were conducted. The effect of contact time, initial phenobarbital concentration, adsorbent mass, and pH was investigated in static conditions. The adsorption results revealed that the biosorbent B3 has a higher affinity for the eliminated compound, with an equilibrium time of 60 min and an adsorption capacity of 47.08 mg/g at an initial concentration of 50 mg/L. The experimental data are consistent with Langmuir and Sips adsorption isotherm models, and with the pseudo-second order and Elovich models for kinetics description. This indicates strong interactions between the adsorbent materials and the pharmaceutical micropollutant. Based on these findings, it appears that, among the tested materials, B3 biosorbent is the most efficient for removing phenobarbital present in low concentrations in water. [ABSTRACT FROM AUTHOR]

Introduction: Water pollution by hydrocarbons is a worldwide concern due to its environmental and economic impact. Several highly effective synthetic sorbent materials have been developed to control oil spills, but the additional storage or disposal costs are high. Objective: To evaluate agro-industrial wastes (sugar cane bagasse and pine sawdust) and their mixtures, as biosorbent materials for the removal of hydrocarbons in water. Materials and Methods: Natural bagasse (NB) and pine sawdust (PS) were sieved to obtain a uniform biomass. The studies are carried out with granulometries (+1 -2 mm) and (+0.315 - 1 mm) for NB and PS for the mass percentages and homogeneity of the fractions. Humidity, real density, apparent density, porosity and Scanning Electron Microscopy (SEM) coupled to EDX were determined for the selected material. To determine the maximum sorption capacity (Ca) of NB and PS, diesel (32.7 °API) was used. An experimental design 2² was carried out. Statgraphics Centurion XV.II software was used for statistical analysis. Results and discussion: The results obtained show that the highest (Ca) was reached with (+0.315 -1 mm) and 80%NB/20%PS and 50%NB/50%PS mixtures. The results obtained show that the most influential variable on (Ca) is the biosorbent concentration. Conclusions: It is concluded that it is possible to use agricultural waste (NB and PS) and their mixtures as biosorbent materials, in non-conventional and sustainable treatments for the removal of hydrocarbons in water. [ABSTRACT FROM AUTHOR]

One of the causes of environmental pollution in Indonesia is inappropriate waste treatment, particularly batik industrial wastewater. Lack of awareness and public knowledge regarding waste management are things that support pervasive pollution. One way to educate students about this issue is through worksheets that teachers can use to teach how to treat waste properly and correctly. This study aimed to describe the arrangement of student worksheets and to analyze the results of a validation test. The steps used in the student worksheets on the manufacture of biosorbents from papaya seeds (Carica papaya l) for the absorption of dyestuffs from the batik industry's liquid waste were based on guided inquiry. The method used is Design-Based Research (DBR) in three stages: analysis, design, and development. The instruments used were a validation questionnaire using correlation analysis techniques and a student worksheet based on guided inquiry. The results of the student worksheet validation test obtained an average value of 0.80, which states that the student worksheets are valid and can be used as a medium for learning or practicum activities. [ABSTRACT FROM AUTHOR]

The residues of olive harvest present high potential to be valorized as bio-based adsorbent (biosorbent), especially olive leaves. In the present study, the use of olive leaf powder (OLP) as biosorbent of lead ions as pollutant model of heavy metals in wastewater was analyzed. Firstly, the OLP was characterized by determining its physio-chemical properties using analytical methods as X-ray fluorescence, X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, and pH of zero-point charge. The optimal operating conditions for lead adsorption capacity by OLP were pH 7.5, contact time 5 min, temperature 20 °C, biosorbent concentration of 2 g L−1, and initial lead concentration of 80 mg L−1. The Langmuir isotherm model fitted better the experimental data than Freundlich model. The adsorption capacity determined by Langmuir model was qe = 68.96 mg g−1. The lead adsorption presented a pseudo-second order kinetics and the study of thermodynamic parameters revealed that the adsorption of lead on OLP is exothermic and spontaneous. [ABSTRACT FROM AUTHOR]

Human and industrial activities have contaminated the groundwater and surface water. This is a significant issue today. Therefore, the analysis of water quality is crucial. The purpose of this study is to evaluate the water quality index (WQI) of groundwater at various locations for physiochemical analysis. For calculating the current water quality status using statistical analysis and in the water quality index, the following parameters were considered: pH, total dissolved solids, total alkalinity, chlorides, hardness, dissolved oxygen, Biochemical oxygen demand, and chemical oxygen demand. The acquired results are compared to the Indian drinking water standard IS: 10500–2012. The investigation of the physicochemical and biological characteristics of this ground water sample indicates that the evaluation of water quality parameters and resources is necessary. In the water quality index of six different places Gudlavalleru, Ainampudi, Penjendra, Gudlavalleru Gudem, Angaluru and Kondiparru. In the six locations the pH value vary from (6.72–8.3), temperature vary from (34 °C-36.5 °C), acidity vary from (15–40), alkanity vary from (10–25), turbidity vary from (0.8–60.4), DO vary from (3.7–6.2), COD vary from (209–477), Iron vary from (3–5), fluorides is zero, phosphorous vary from (0–0.5), ammonium vary from (0–1), nitrates vary from (0–5), chlorides vary from (375–575), hardness vary from (200–505), nitrites vary from (0–1), total solids vary from (729–1573), suspended solids vary from (468–971) and dissolved solids vary from (301–602). Using dry flowers biosorbents for biosorptions of heavy metals from polluted water or treat contaminated groundwater. Biological reactions occur to control the concentration of contaminated water when fine, dried powder of flower waste biosorbents is added to contaminated water. In this study, we employ four different flower waste biosorbents, including Targets or marigold flower waste, Ixora-coccinea flower waste, Hibiscus flower waste, and Allamanda flower waste. The Targets or marigold flower waste biosorbents have the highest performance for removing toxic metals from contaminated water among the four flower waste biosorbents. Further optimization of the various parameters, i.e. biosorbents dosage, contact time, pH, temperature, and agitation speed, was performed on Targets or marigold flowers waste biosorbents in order to increase pollutant biosorption. Further research is required into the mechanisms of biosorbents, the kinetics and reusability of metal uptake, the recovery and regeneration of biosorbents, process design, and the commercial application of Targets or marigold flower refuse biosorbents.

Removal of lead (Pb) by sorbents through adsorption is one of the effective methods to remediate contaminated aquatic systems. This study assesses the lead removal potentials of various cost-effective, readily available biosorbents such as, coirpith, cocopeat and poultry manure from waste water in a batch incubation experiment. The biosorbents were characterised and the effect of sorbent dosage, Pb2+ concentration at different time intervals on Pb sorption was studied and the data were fitted to various kinetic models to understand the mechanism of adsorption. The FTIR peaks revealed the involvement of hydroxyl and carboxylic groups in Pb sorption and SEM micrographs shows highly porous surface of poultry manure that enhances Pb sorption. Higher Pb adsorption (71.2%) rate was observed in poultry manure than coirpith (40.4%) and cocopeat (47.6%) which increased with increasing sorbent dosage (62.6 to 79.3%) and time intervals (0 to 78.9%). Kinetic modelling of sorption data revealed that pseudo second-order kinetic model best explained the adsorption by cocopeat (R2 = 0.96 to 0.99) and poultry manure (R2 = 0.97 to 1.00) while zero-order kinetics model described it better for coirpith (R2 = 0.99 to 1.00). Chemisorption was the dominant mechanism operating in cocopeat and poultry manure; while, surface sorption was dominant in coirpith. On the other hand, least desorption was found in poultry manure (0.75%) than coirpith (19.0%) and cocopeat (1.58%) which decreased with increasing sorbent dosage at successive time intervals. Hence, it could be concluded that, poultry manure is the effective sorbent that can be utilised for the removal of Pb from wastewater. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive analysis of the adsorbent capacity of five distinctly different biosorbents derived from untreated biomasses. The optimal adsorption capacity of seaweed (Laminaria digitata), horse chestnut husk, hazelnut husk, rapeseed residue, and whitewood to remove methylene blue (MB) dye was assessed by analysing the effects of particle size, pH, temperature, and initial dye concentrations. Furthermore, the adsorption kinetics, isotherms, and adsorption thermodynamics were investigated. The results showed that relatively high MB adsorption capacity was achieved by Laminaria digitata (~180 mg/g), in addition to a reasonable MB adsorption capacity of horse chestnut husk (~130 mg/g), hazelnut husk (~110 mg/g), and rapeseed residue (~80 mg/g). However, whitewood provides a relatively low adsorption capacity of below 20 mg/g. The best fit with experimental results regardless of biosorbent type was a pseudo-second-order kinetic model with the lowest mean absolute percentage error (ε, MAPE < 2.5%) and the highest correlation coefficients (R2 > 0.99). Although the pseudo-second-order kinetic model is often associated with chemisorption, the low enthalpy values (<29.30 kJ/mol) typically suggest that the adsorption process is more characteristic of physisorption, which involves weaker van der Waals forces rather than the stronger covalent bonds of chemisorption. This proposed a multi-step adsorption process involving both physisorption and chemisorption. The adsorption isotherm of Langmuir showed superior fitting results for Laminaria digitata and hazelnut husk. In contrast, rapeseed residue and horse chestnut husk fit better with the Freundlich adsorption isotherm. The Langmuir adsorption isotherms showed a maximum adsorption capacity of ~500 mg/g for Laminaria digitata, followed by horse chestnut husk (~137 mg/g), hazelnut husk (~120 mg/g), and rapeseed residue (~85 mg/g). The Gibbs free energy was negative for Laminaria digitata < horse chestnut husk < hazelnut husk < 0, which suggests that the removal of MB is thermodynamically favourable, as the adsorption process occurs spontaneously. The results of the study indicate that MB dye removal using untreated biomasses has the potential to be a low-cost valorisation option in the holistic whole life cycle valorisation pathway for Laminaria digitata, horse chestnut husk, and hazelnut husk. [ABSTRACT FROM AUTHOR]

In this work, is proposed an analytical method for the determination of nickel in natural water and sediment samples using solid-phase extraction with a mini-column of bamboo fibres modified with 5-Br-PADAP and determination by flame atomic absorption spectrometry. Applying the characterisation techniques of fresh bamboo fibre aimed to define the morphology of the fibre and its physical characteristics. Turning to the optimisation of the variables for the adsorptive process of nickel. The system allows the determination of nickel with a limit of detection (LOD) of 0.75 μg L−1 and a limit of quantitation (LOQ) of 2.50 μg L−1. The precision was expressed as a relative standard deviation (RSD) of 3.4 and 3.8% for a nickel concentration of 20.0 and 50.0 μg L−1 respectively. The value of 78.0 was determined as the value for the enrichment factor. The accuracy was confirmed with spike tests with recuperations varying from 91% to 106% and 93% to 104% for water and sediment samples, respectively, and by comparison with the certified sample. The procedure was applied for nickel determination in natural water and sediment samples. The achieved concentrations varied from 4.0–53.2 and 3.7–55.8 µg L−1 for water and sediment samples, respectively. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate the possibility of applying the dried biomass of E. gracilis var. bacillaris as a biosorbent for the removal of Cd. Experiments were carried out under conditions of batch systems involving aqueous solutions labelled with 109CdCl2. From the kinetics of Cd biosorption, it can be assumed that the Cd removal was a rapid process that achieved the concentration equilibrium of [Cd]biomass:[Cd]solution in the first minutes of the interaction. In individual experiments, the effect of solution pH, initial biosorbent, or Cd concentration was evaluated. According to MINEQL+ speciation modelling, it was found that the biosorption of Cd decreased linearly corresponding to a decrease in the proportion of Cd2+ in the solution. The biosorption data were well fitted to the Langmuir model of adsorption isotherm in comparison with the Freundlich model. The maximum biosorption capacity of the dried biomass of E. gracilis var. bacillaris for the removal of Cd was predicted and reached the value Qmax = 0.13 mmol/g or 14.1 mg/g (d.w.), respectively. [ABSTRACT FROM AUTHOR]

Various processes designed for the humification (HF) of animal husbandry wastes, primarily bird droppings, reduce their volumes, solve environmental problems, and make it possible to obtain products with artificially formed humic substances (HSs) as analogues of natural HSs, usually extracted from fossil sources (coal and peat). This review studies the main characteristics of various biological and physicochemical methods of the HF of animal wastes (composting, anaerobic digestion, pyrolysis, hydrothermal carbonation, acid or alkaline hydrolysis, and subcritical water extraction). A comparative analysis of the HF rates and HS yields in these processes, the characteristics of the resulting artificial HSs (humification index, polymerization index, degree of aromaticity, etc.) was carried out. The main factors (additives, process conditions, waste pretreatment, etc.) that can increase the efficiency of HF and affect the properties of HSs are highlighted. Based on the results of chemical composition analysis, the main trends and preferences with regard to the use of HF products as complex biomimetics are discussed. [ABSTRACT FROM AUTHOR]

Water contamination by arsenic (As) is widespread and is posing serious health threats globally. Hence, As removal techniques/adsorbents need to be explored to minimize potentials hazards of drinking As-contaminated waters. A column scale sorption experiment was performed to assess the potential of three biosorbents (tea waste, wheat straw and peanut shells) to remove As (50, 100, 200 and 400 µg L−1) from aqueous medium at a pH range of 5–8. The efficiency of agricultural biosorbents to remove As varies greatly regarding their type, initial As concentration in water and solution pH. It was observed that all of the biosorbents efficiently removed As from water samples. The maximum As removal (up to 92%) was observed for 400 µg L−1 initial As concentration. Noticeably, at high initial As concentrations (200 and 400 μg L−1), low pH (5 and 6) facilitates As removal. Among the three biosorbents, tea waste biosorbent showed substantial ability to minimize health risks by removing As (up to 92%) compared to peanut shells (89%) and wheat straw (88%). Likewise, the values of evaluated risk parameters (carcinogenic and non-carcinogenic risk) were significantly decreased (7–92%: average 66%) after biosorption experiment. The scanning electron microscopy, Fourier transform infrared spectroscopy, energy-dispersive X-ray and X-ray diffraction analyses confirmed the potential of biosorbents to remediate As via successful loading of As on their surfaces. Hence, it can be concluded that synthesized biosorbents exhibit efficient and ecofriendly potential for As removal from contaminated water to minimize human health risk. [ABSTRACT FROM AUTHOR]

To ascertain their potential for heavy metal pollution remedy, we studied the adsorption mechanism of cadmium onto scallop shells and the interactions between the heavy metal and the shell matrix. Intact shells were used to investigate the uptake and diffusion of the metal contaminant onto the shell carbonatic layers, as well as to evaluate the distribution of major and trace elements in the matrix. LA-ICPMS measurements demonstrate that Cd is adsorbed on a very thin layer on the inner and outer surfaces of the shell. Structural and thermal analyses showed the presence of 9 wt.-% of a CdCO3 phase indicating that the adsorption is mainly a superficial process which involves different processes, including ion exchange of Ca by Cd. In addition, organic components of the shell could contribute to adsorption as highlighted by different metal uptake observed for shells with different colours. In particular, darker shells appeared to adsorb more contaminant than the white ones. The contribution of the organic shell components on the adsorption of heavy metals was also highlighted by the element bulk content which showed higher concentrations of different metals in the darker specimen. Raman spectroscopy allowed to identify the pigments as carotenoids, confirmed by XRD measurements which highlighted the presence of astaxanthin phases. The results presented here provide new insights into the Cd adsorption mechanism highlighting the important contribution given by the organic components present in the biogenic carbonate matrix. Furthermore, the high efficiency of Cd removal from water by scallop shells, supported by adsorption kinetic and isotherm studies, has been demonstrated.

Heavy metal contamination in wastewater is a significant concern for human health and the environment, prompting increased efforts to develop efficient and sustainable removal methods. Despite significant efforts in the last few decades, further research initiatives remain vital to comprehensively address the long-term performance and practical scalability of various adsorption methods and adsorbents for heavy metal remediation. This article aims to provide an overview of the mechanisms, kinetics, and applications of diverse adsorbents in remediating heavy metal-contaminated effluents. Physical and chemical processes, including ion exchange, complexation, electrostatic attraction, and surface precipitation, play essential roles in heavy metal adsorption. The kinetics of adsorption, influenced by factors such as contact time, temperature, and concentration, directly impact the rate and effectiveness of metal removal. This review presents an exhaustive analysis of the various adsorbents, categorized as activated carbon, biological adsorbents, agricultural waste-based materials, and nanomaterials, which possess distinct advantages and disadvantages that are linked to their surface area, porosity, surface chemistry, and metal ion concentration. To overcome challenges posed by heavy metal contamination, additional research is necessary to optimize adsorbent performance, explore novel materials, and devise cost-effective and sustainable solutions. This comprehensive overview of adsorption mechanisms, kinetics, and diverse adsorbents lays the foundation for further research and innovation in designing optimized adsorption systems and discovering new materials for sustainable heavy metal remediation in wastewater.

In this study, alginate-encapsulated biosorbents have been prepared from agricultural wastes viz. peanut shells and rice husks. Biosorbents in this study were referred as En-PS and En-RH for the adsorbents prepared from peanut shells and rice husks, respectively. The characteristics of the adsorbents were thoroughly investigated using scanning electron microscope, X-ray diffractometer, surface area analyzer, and Fourier-transform infrared spectrophotometer instruments. The prepared biosorbents were used as adsorbents for cationic methylene blue (MB) dye in water. The encapsulation process using sodium alginate simplified the separation of adsorbent from the water after the adsorption process. The adsorptions of MB onto both adsorbents followed the pseudo-second order model and fitted both Langmuir and Freundlich isotherm models. Thermodynamic studies revealed that the adsorption of MB onto En-PS and En-RH was a spontaneous and endothermic process with the ΔG° reaction of -1.694 and -2.028 kJ/mol at the room temperature, respectively. Biosorbents could be used in the adsorption-desorption process for up to 3 cycles.

Although a diverse of different superhydrophobic biomaterials have been developed, facile preparation of recyclable bulk superhydrophobic biomaterials is still a great challenge. In this paper, one-step preparation of superhydrophobic rod-shaped corn straw (RCS) can be achieved by utilizing the hydroxyl-driven silylation process of growing polysiloxane nanofilaments on the surface of the RCS. The water contact angle of the prepared RCS is as high as 159°, showing excellent water repellency. The prepared RCS can selectively absorb organic solvents and oils from water and shows strong oil retention capacity. The absorption capacity of the prepared RCS is not affected by the length and diameter of the straw itself, which makes the utilization of the pristine straw more convenient. The prepared RCS can be used continuously for at least 10 times, showing a good recycling ability. This work provides a new simple and effective idea for the synthesis of bulk straw-based superhydrophobic materials. [ABSTRACT FROM AUTHOR]

Presence of colors, organic surface finishing agents and surfactants in textile industry effluent makes it highly detrimental for surrounding environment. Hence the effluent from textile industry needs treatment for removal of these colors, organic and inorganic components before its disposal. Hence applicability of low cost and environmental friendly biosorbents, Azospirillium biofertilizer and Rhizobium biofertilizer were investigated for removal of Congo red dye. Batch experimentation was carried out to check operating parameters like, temperature, dose of adsorbent, pH, agitation speed, contact time and initial concentration. The biosorption capacity for Congo red dye was 67.114 and 101.01 mg/g, for Azospirillium biofertilizer and Rhizobium biofertilizer, respectively at optimized parameters. RL factor was 0.558 and 0.568 for Azospirillium biofertilizer and Rhizobium biofertilizer. The data showed combination of interaction-based separation through better fitting of Langmuir isotherm compared to Freundlich. Its separation is well described by Pseudo-second order and intraparticle diffusion model. Adsorption was favorable at lower temperature suggesting exothermic and spontaneous nature. Reusability for Azospirillium biofertilizer and Rhizobium biofertilizer was checked for 25 mg/land. While the biological nature of Azospirillium and Rhizobium biofertilizer makes removal of Congo red dye environmentally benign. [ABSTRACT FROM AUTHOR]

Heavy metal contamination in wastewater is a significant concern for human health and the environment, prompting increased efforts to develop efficient and sustainable removal methods. Despite significant efforts in the last few decades, further research initiatives remain vital to comprehensively address the long-term performance and practical scalability of various adsorption methods and adsorbents for heavy metal remediation. This article aims to provide an overview of the mechanisms, kinetics, and applications of diverse adsorbents in remediating heavy metal-contaminated effluents. Physical and chemical processes, including ion exchange, complexation, electrostatic attraction, and surface precipitation, play essential roles in heavy metal adsorption. The kinetics of adsorption, influenced by factors such as contact time, temperature, and concentration, directly impact the rate and effectiveness of metal removal. This review presents an exhaustive analysis of the various adsorbents, categorized as activated carbon, biological adsorbents, agricultural waste-based materials, and nanomaterials, which possess distinct advantages and disadvantages that are linked to their surface area, porosity, surface chemistry, and metal ion concentration. To overcome challenges posed by heavy metal contamination, additional research is necessary to optimize adsorbent performance, explore novel materials, and devise cost-effective and sustainable solutions. This comprehensive overview of adsorption mechanisms, kinetics, and diverse adsorbents lays the foundation for further research and innovation in designing optimized adsorption systems and discovering new materials for sustainable heavy metal remediation in wastewater. [ABSTRACT FROM AUTHOR]

The removal of pharmaceutically active compounds present in relatively low concentration in wastewater is critical. This is because they have a severe, negative impact on life and the environment. To address this issue, adsorption was used, which is an effective wastewater treatment method for removing substances found in low concentrations in water. This study compared the adsorption performance of active carbon to three biosorbents derived from Adansonia digitata shells. The adsorbents were prepared and characterized using TGA, SEM, EDX, and FTIR analyses and pHPZC. To better understand the adsorption process, equilibrium and reaction kinetics studies were conducted. The effect of contact time, initial phenobarbital concentration, adsorbent mass, and pH was investigated in static conditions. The adsorption results revealed that the biosorbent B3 has a higher affinity for the eliminated compound, with an equilibrium time of 60 min and an adsorption capacity of 47.08 mg/g at an initial concentration of 50 mg/L. The experimental data are consistent with Langmuir and Sips adsorption isotherm models, and with the pseudo-second order and Elovich models for kinetics description. This indicates strong interactions between the adsorbent materials and the pharmaceutical micropollutant. Based on these findings, it appears that, among the tested materials, B3 biosorbent is the most efficient for removing phenobarbital present in low concentrations in water.

Antiviral drugs such as lamivudine have been globally identified in the environment and marked as emerging pollutants of concern due to their bioactive extremity. Following therapeutic uses, approximately 70% of the oral dose of lamivudine is eliminated renally as the parent drug. Concerns has been raised for neighbouring aquatic bodies due to effluent produced from production plants containing high concentrations of antiviral drugs. Antiviral drugs, such as lamivudine, are extremely bioactive, prompting interest in their urgent removal from the environment. The purpose of the present study was to optimize the removal of lamivudine from the synthetic solution using jamun seed (JS) (Syzygium cumini) biochar. The influence of sorption parameters such as pH, lamivudine concentration, adsorbent dosage, contact time, and calcination temperatures on the removal of lamivudine was investigated and optimized using a response surface methodology (SRM) based on optimal design. The results indicated that, a quadratic model best fits data with a model regression coefficient R2, adjusted R2, and predicted R2 of 0.9934, 0.9761 and 0.8340, respectively. The JS biochar calcined at 750 °C, at pH 8, initial lamivudine concentration of 10 ppm and contact time of 30 min indicated a maximum experimental removal efficiency of 84.9%. The residual standard error (RSE) value was 3.5% implying that the model was reliable. Isotherm data for the adsorption of lamivudine on JS biochar followed the Freundlich isotherm, with an R2 value of 0.9977 while R2 for the modified Langmuir model was 0.9852. These findings indicated that JS biochar is potentially useful for removal of lamivudine, and other organics from contaminated water and wastewater effluents. Therefore, this study presents an environmentally friendly remedy against lamivudine for a healthier ecology.

Access to drinkable water is becoming more and more challenging due to worldwide pollution and the cost of water treatments. Water and wastewater treatment by adsorption on solid materials is usually cheap and effective in removing contaminants, yet classical adsorbents are not sustainable because they are derived from fossil fuels, and they can induce secondary pollution. Therefore, biological sorbents made of modern biomass are increasingly studied as promising alternatives. Indeed, such biosorbents utilize biological waste that would otherwise pollute water systems, and they promote the circular economy. Here we review biosorbents, magnetic sorbents, and other cost-effective sorbents with emphasis on preparation methods, adsorbents types, adsorption mechanisms, and regeneration of spent adsorbents. Biosorbents are prepared from a wide range of materials, including wood, bacteria, algae, herbaceous materials, agricultural waste, and animal waste. Commonly removed contaminants comprise dyes, heavy metals, radionuclides, pharmaceuticals, and personal care products. Preparation methods include coprecipitation, thermal decomposition, microwave irradiation, chemical reduction, micro-emulsion, and arc discharge. Adsorbents can be classified into activated carbon, biochar, lignocellulosic waste, clays, zeolites, peat, and humic soils. We detail adsorption isotherms and kinetics. Regeneration methods comprise thermal and chemical regeneration and supercritical fluid desorption. We also discuss exhausted adsorbent management and disposal. We found that agro-waste biosorbents can remove up to 68–100% of dyes, while wooden, herbaceous, bacterial, and marine-based biosorbents can remove up to 55–99% of heavy metals. Animal waste-based biosorbents can remove 1–99% of heavy metals. The average removal efficiency of modified biosorbents is around 90–95%, but some treatments, such as cross-linked beads, may negatively affect their efficiency. [ABSTRACT FROM AUTHOR]

An innovative methodology was implemented for removing arsenic from aqueous solution by developing successive biosorption experiments. Considering the high affinity of As oxyanions toward Fe(III) oxides, the biosorption of Fe(II) was first conducted using nine biomaterials—aquatic and terrestrial invasive species, biowastes, local plants. Pistia stratiotes, an invasive alien species presenting the highest concentration of adsorbed Fe(II), was selected for a detailed investigation of As(V) removal from wastewater. After oxidation of the biosorbent into Fe(III), it yielded to a 92% removal efficiency determined by GFAAS and an excellent maximum biosorption capacity of 5.1 mg.g−1. The biosorbent was characterized by MP-AES and HRTEM-EDX. The adsorption mechanisms for iron and arsenic have been studied via theoretical models and the Langmuir isotherms and pseudo-second-order kinetics models revealed excellent linearity and highlighted the robustness of the method. These promising results were developed to build a pilot for As(V) removal from the Russec river (Orbiel Valley, France), polluted with arsenic. [ABSTRACT FROM AUTHOR]

In this study, alginate-encapsulated biosorbents have been prepared from agricultural wastes viz. peanut shells and rice husks. Biosorbents in this study were referred as En-PS and En-RH for the adsorbents prepared from peanut shells and rice husks, respectively. The characteristics of the adsorbents were thoroughly investigated using scanning electron microscope, X-ray diffractometer, surface area analyzer, and Fourier-transform infrared spectrophotometer instruments. The prepared biosorbents were used as adsorbents for cationic methylene blue (MB) dye in water. The encapsulation process using sodium alginate simplified the separation of adsorbent from the water after the adsorption process. The adsorptions of MB onto both adsorbents followed the pseudo-second order model and fitted both Langmuir and Freundlich isotherm models. Thermodynamic studies revealed that the adsorption of MB onto En-PS and En-RH was a spontaneous and endothermic process with the ΔG° reaction of -1.694 and -2.028 kJ/mol at the room temperature, respectively. Biosorbents could be used in the adsorptiondesorption process for up to 3 cycles. [ABSTRACT FROM AUTHOR]

The present research focuses on the application of peanut and walnut shells, in their natural state, for the removal of methylene blue (MB) from water solutions in batch and dynamic (flow-through) conditions. Under batch conditions, at a 100 mg/L MB concentration of aqueous solution, the optimum dose of the studied biosorbents was determined to be 2.5 g/L, reaching about 95–97% efficiency of MB removal for both materials. Langmuir and Freundlich isotherms were used to model and evaluate the experimental data under different initial concentrations of MB (25 to 100 mg/L). The determined maximum adsorption capacities are 41.50 mg/g for walnut shells and 46.80 mg/g for peanut shells. Under flow-through conditions, breakthrough curves are determined for three sizes of fractions (<0.25 mm, 0.315–0.5 mm, and 0.8–1.6 mm). For peanut shells, the smaller the particle size, the higher the adsorption capacity and the column breakthrough time. For walnut shells, however, the particle size seems to have a more complex influence on the adsorption process parameters, and this phenomenon deserves future investigation. The adsorption capacity for one and the same fraction size of 0.315–0.5 mm and initial MB concentration of 50 mg/L is higher under dynamic flow conditions, i.e., 51 mg/g compared to 20 mg/g for walnut shells and 46 mg/g compared to 17.5 mg/g for peanut shells. [ABSTRACT FROM AUTHOR]

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Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Heavy metal contamination from anthropogenic activities has an adverse effect on the environment due to its cytotoxicity, carcinogenicity and mutagenicity. Environment harbours microorganisms, some of which have been found to modify physico-chemical conditions of their surrounding environment through certain processes such as detoxification, metal homeostasis, precipitation, redox transformations etc. Investigations in the past have shown that short term contact with metals of certain bacteria causes the selection of resistant bacteria within weeks, while a prolonged exposure showed selected strains able to thrive better. Hence biotic methods could assist removal of heavy metals based on biosorption or bioaccumulation by microorganisms, which are cost-effective and environmental friendly in the long run. Microbial remediation is influenced by biotic and environmental factors as also the contamination site characteristics. The aim of this paper is to highlight and review some of the mechanisms of microbial remediation through techniques such as biostimulation, bioaugmentation etc.

Mobilization of heavy metals in the environment has been a matter of concern for several decades due to their toxicity for humans, environments, and other living organisms. In recent years, use of inexpensive and abundantly available biosorbents generated from fibrous plant-based food-waste materials to remove heavy metals has garnered considerable research attention. The aim of this review is to investigate the applicability of using fibrous plant-based food waste, which comprises different components such as pectin, hemicellulose, cellulose, and lignin, to remove heavy metals from wastewater. This contribution confirms that plant-fiber-based food waste has the potential to bind heavy metals from wastewater and aqueous solutions. The binding capacities of these biosorbents vary depending on the source, chemical structure, type of metal, modification technology applied, and process conditions used to improve functionalities. This review concludes with a discussion of arguments and prospects, as well as future research directions, to support valorization of fibrous plant-based food waste as an efficient and promising strategy for water purification. [ABSTRACT FROM AUTHOR]

Biosorbent composites like chitin, alginate, moss, xanthene, and cotton can be derived from biotic species such as plants, algae, fungi, and bacteria which can be used for the exclusion of both organic and inorganic toxicants from sewage, industrial effluent, polluted soils, and many more. The use of composites in place of raw substrates like alginate and chitin increases the adsorption capacity as CS4CPL1 beads increase the adsorption capacity for copper and nickel from 66.7 mg/g and 15.3 mg/g in the case of alginate microsphere to 719.38 mg/g and 466.07 mg/g respectively. Biosorbent fabricated from algae Chlorella vulgaris having surface area of 12.1 m2/g and pore size of 13.7 nm owing to which it displayed a higher adsorption capacity for Pb 0.433 mmol/g indicating their potential as an efficient biosorbent material. This article contains detailed information related to heavy metals as well as biosorbent that includes different isotherms, kinetics, techniques to estimate heavy metal concentration, removal methods, and adverse health effects caused due to heavy metal pollution. Apart from the above recovery and reuse of biosorbent, correlation with the sustainable development goals has also been included. [ABSTRACT FROM AUTHOR]

Phosphorus acts as a vital part in the improvement of environment, manufacturing and agriculture. However, it can also become a contaminant in water bodies, posing a danger to the human, animals and the ecosystems. To address this issue, different methods exist for removing phosphorus from water, with bio-sorption being a mainly effective and eco-friendly option. Plant leaf biosorbents offer different levels of effectiveness, depending on the taxonomic group and pre-treatment of the plant, among other factors. In this research, locally available plant leaf biosorbents, including neem, javapalm, guava, sapota, custard apple, and mango leaves, were measured for their capability to eliminate phosphorus from water. Results indicated that mango leaves were the most effective, followed by javapalm, sapota, custard apple, neem, and guava leaves. The optimal conditions for phosphorus removal were a normal pH of 4–8, 1.2 g quantity, 60 min of contact time, a temperature of 25 °C, and a rotation speed of 100 rpm. Regeneration and reapplication of the plant leaf biosorbents can further improve the efficiency of the process.

Potentially toxic elements in water is one of the important environmental problems. In this study, it was aimed to produce an environmentally friendly and cost-effective biosorbent using sustainable hemp biomass. The chemical composition of hemp biosorbents was characterized by FTIR, SEM, and XRD, and the results showed that the biosorbent could be a good alternative. A batch system was used to investigate the effects of initial concentration, pH, contact time, and temperature on the removal performance of Cu (II) and Zn (II) ions. The statistical analysis was performed, and the amount of adsorbed substance, kinetic values, and experiment results were evaluated for suitability. Kinetic data determined the best fit to pseudo-second-order kinetics for Cu (II) and Zn (II) ions. Adsorption determined the Langmuir model for Cu (II) ions and the Freundlich model for Zn (II) ions. The maximum adsorption capacity in the batch system was determined as 25.59 mg/g for Cu (II) and 12.97 mg/g for Zn (II) ions. The obtained thermodynamic data confirmed the endothermic nature of the adsorption. In desorption studies, after three cycles, the adsorption efficiency decreased from 83.3% to 52.8% for Cu (II) and from 82.1% to 49.7% for Zn (II). Study results showed that hemp biosorbent may be an alternative adsorbent that can be used to remove PTEs from wastewater.

Various processes designed for the humification (HF) of animal husbandry wastes, primarily bird droppings, reduce their volumes, solve environmental problems, and make it possible to obtain products with artificially formed humic substances (HSs) as analogues of natural HSs, usually extracted from fossil sources (coal and peat). This review studies the main characteristics of various biological and physicochemical methods of the HF of animal wastes (composting, anaerobic digestion, pyrolysis, hydrothermal carbonation, acid or alkaline hydrolysis, and subcritical water extraction). A comparative analysis of the HF rates and HS yields in these processes, the characteristics of the resulting artificial HSs (humification index, polymerization index, degree of aromaticity, etc.) was carried out. The main factors (additives, process conditions, waste pretreatment, etc.) that can increase the efficiency of HF and affect the properties of HSs are highlighted. Based on the results of chemical composition analysis, the main trends and preferences with regard to the use of HF products as complex biomimetics are discussed.

This paper presents a comprehensive analysis of the adsorbent capacity of five distinctly different biosorbents derived from untreated biomasses. The optimal adsorption capacity of seaweed (Laminaria digitata), horse chestnut husk, hazelnut husk, rapeseed residue, and whitewood to remove methylene blue (MB) dye was assessed by analysing the effects of particle size, pH, temperature, and initial dye concentrations. Furthermore, the adsorption kinetics, isotherms, and adsorption thermodynamics were investigated. The results showed that relatively high MB adsorption capacity was achieved by Laminaria digitata (~180 mg/g), in addition to a reasonable MB adsorption capacity of horse chestnut husk (~130 mg/g), hazelnut husk (~110 mg/g), and rapeseed residue (~80 mg/g). However, whitewood provides a relatively low adsorption capacity of below 20 mg/g. The best fit with experimental results regardless of biosorbent type was a pseudo-second-order kinetic model with the lowest mean absolute percentage error (ε, MAPE < 2.5%) and the highest correlation coefficients (R2 > 0.99). Although the pseudo-second-order kinetic model is often associated with chemisorption, the low enthalpy values (Laminaria digitata and hazelnut husk. In contrast, rapeseed residue and horse chestnut husk fit better with the Freundlich adsorption isotherm. The Langmuir adsorption isotherms showed a maximum adsorption capacity of ~500 mg/g for Laminaria digitata, followed by horse chestnut husk (~137 mg/g), hazelnut husk (~120 mg/g), and rapeseed residue (~85 mg/g). The Gibbs free energy was negative for Laminaria digitata < horse chestnut husk < hazelnut husk < 0, which suggests that the removal of MB is thermodynamically favourable, as the adsorption process occurs spontaneously. The results of the study indicate that MB dye removal using untreated biomasses has the potential to be a low-cost valorisation option in the holistic whole life cycle valorisation pathway for Laminaria digitata, horse chestnut husk, and hazelnut husk.

The aim of this work was to evaluate the possibility of applying the dried biomass of E. gracilis var. bacillaris as a biosorbent for the removal of Cd. Experiments were carried out under conditions of batch systems involving aqueous solutions labelled with 109CdCl2. From the kinetics of Cd biosorption, it can be assumed that the Cd removal was a rapid process that achieved the concentration equilibrium of [Cd]biomass:[Cd]solution in the first minutes of the interaction. In individual experiments, the effect of solution pH, initial biosorbent, or Cd concentration was evaluated. According to MINEQL+ speciation modelling, it was found that the biosorption of Cd decreased linearly corresponding to a decrease in the proportion of Cd2+ in the solution. The biosorption data were well fitted to the Langmuir model of adsorption isotherm in comparison with the Freundlich model. The maximum biosorption capacity of the dried biomass of E. gracilis var. bacillaris for the removal of Cd was predicted and reached the value Qmax = 0.13 mmol/g or 14.1 mg/g (d.w.), respectively.

In this study, waste flax fibers with different levels of cellulosic and noncellulosic components were obtained by oxidative and alkali treatments and used to assess the influence of the fiber’s structural and chemical properties on the biosorption of lead ions. Scanning electron microscopy was used for the characterization of the flax fibers’ surface morphology, while the physicochemical properties of the fibers’ surface were determined by the streaming potential method, and Fourier transform infrared spectroscopy. Alkaline treatment decreased, while oxidative increased the crystallinity index of flax fibers by approximately 10%, due to the changes in the content of cellulosic components. Adsorption of lead ions was studied in detail, including kinetics, isotherms, and thermodynamic parameters analysis. It was shown that the amount and distribution of oxygen-containing groups, originating from cellulosic components, have the highest influence on the adsorption capacity of flax fibers, increasing Langmuir adsorption capacity from 12.76 mg g−1 for untreated to 21.9 and 79.9 mg g−1 for alkali-treated and oxidized fibers, respectively. Obtained negative values of ∆GӨ (−4.874 to −0.807 kJ mol−1) and ∆HӨ (−42.81 to −13.65 kJ mol−1) indicated that the adsorption of lead ions onto flax fibers is a spontaneous and endothermic process, which occurs through electrostatic attraction and ion-exchange. The results presented in this work demonstrate that the waste flax fibers of suitable chemical composition may be used as sustainable and renewable low-cost biosorbents.

The scarcity of clean water resources combined with other environmental and anthropogenic effects have urged the development of advanced technology for wastewater treatment. Adsorption attracts great attention as a cost-effective technique for the remediation of contaminated water. Despite a broad variety of adsorbents existing in the literature, agriculture waste-derived biosorbents appear to hold the greatest promise for the adsorption of emerging contaminants. Herein, this review introduces the recent developments of biosorbents in the adsorption field. The role of biosorbents in the green chemistry principle and their contribution towards Sustainable Development Goals (SDGs) are discussed. Different types of modifications of biosorbents including activation and modification of magnetic, non-magnetic nanoparticles and polymers are systematically reviewed. Besides, the application of modified biosorbents in the adsorption of heavy metals, dyes, PAHs and oils along with their respective mechanisms are analyzed. Apart from this, the potential practical application of biosorbents is canvassed through introducing simultaneous adsorption of pollutants, usage of real industrial wastewater matrix and reusability performance. Finally, the recommendations for future adsorption studies are presented. This review is anticipated to critically review and explore the potential of biosorbents as economical and green candidates for the adsorption of emerging pollutants.