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The Evolution of Sorbents Based on Natural Materials for Wastewater Pollution Control

A special issue of Water (ISSN 2073-4441). This special issue belongs to the section "Wastewater Treatment and Reuse".

Deadline for manuscript submissions: closed (30 September 2023) | Viewed by 24266

Special Issue Editors


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Guest Editor
Faculty of Food Technology Osijek, University of Osijek, F. Kuhača 20, 31000 Osijek, Croatia
Interests: food chemistry; food analysis; food safety; innovative food production; sustainability
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Faculty of Food Technology Osijek, University of Osijek, F. Kuhača 20, 31000 Osijek, Croatia
Interests: adsorption; pollutant removal from water and wastewater; environmental chemistry; water protection
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Principal Research Fellow, Department for Catalysis and Chemical Engineering, University of Belgrade - Institute of Chemistry, Technology, and Metallurgy, National Institute of the Republic of Serbia, Njegoševa 12, 11000 Belgrade, Serbia
Interests: adsorption process; biosorption process; catalysis; phylosilciates; hybrid materials; material synthesis and functionalization; characterization; wastewater treatment

Special Issue Information

Dear Colleagues,

Wastewater treatment involves the use of mechanical, physical, chemical, and biological processes to remove various chemical pollutants from wastewater. Biological wastewater treatment, also known as the conventional method, is a common and widely used treatment method. However, conventional wastewater treatment plants are not sufficiently efficient in removing pollutants that cannot be metabolized by microorganisms, e.g., detergents, pesticides, dyes, drug residues, personal care product residues, heavy metals, phenols, PCBs, PAHs, and trihalomethanes. Many of these substances are classified as contaminants of emerging concern, posing a significant risk to the aquatic environment or a hazard that is transmitted through them. Among the many methods for their removal, sorption appears to be one of the most promising, as it has proven to be simple, cost-effective, highly efficient, and versatile in dealing with chemically diverse compounds that require removal. To make it even more cost-effective and sustainable, sorbents based on natural materials of microbial, plant, animal, and mineral origin are being studied in detail. These materials (e.g., active or inactive microbial biomass, chitin, lignocellulosic materials, bones, feathers, eggshells, clay minerals, metal oxides) can be used in either unmodified or novel form, and more superior sorbents (e.g., biochar or composites) can be obtained through a variety of modifications or functionalization.

This Special Issue is devoted to new research and recent contributions on the synthesis, characteristics, and application of sorbents from natural materials and their use in the removal of pollutants from wastewater.

Dr. Natalija Velić
Dr. Marija Stjepanović
Dr. Nataša Jović-Jovičić
Guest Editors

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Keywords

  • pollutant removal
  • wastewater
  • sorbent
  • adsorption
  • biosorption
  • ion exchange
  • modification
  • functionalization
  • composite materials
  • biochar

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Published Papers (10 papers)

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Research

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22 pages, 4425 KiB  
Article
Valorization of Pine Cones (Pinus nigras) for Industrial Wastewater Treatment and Crystal Violet Removal: A Sustainable Approach Based on Bio-Coagulants and a Bio-Adsorbent
by Ouiem Baatache, Kerroum Derbal, Abderrezzaq Benalia, Ines Aberkane, Qamar Ezamene Guizah, Amel Khalfaoui and Antonio Pizzi
Water 2024, 16(2), 260; https://doi.org/10.3390/w16020260 - 11 Jan 2024
Cited by 12 | Viewed by 2416
Abstract
Pine cones are a widely available and abundant natural resource in Algeria, and they are rich in active molecules. This study investigated the valorization of Pine cones as a natural and abundant bio-coagulant in raw form (powder) and extract form. The active components [...] Read more.
Pine cones are a widely available and abundant natural resource in Algeria, and they are rich in active molecules. This study investigated the valorization of Pine cones as a natural and abundant bio-coagulant in raw form (powder) and extract form. The active components of the Pine cones were extracted using two solvents, distilled water (DW) and NaCl, to obtain coagulants (proteins, polyphenols, and carbohydrates) for the treatment and improvement of industrial water quality parameters (discharge from a processing plant and tomato production) and an adsorbent (residue extract, RE). The recovered bio-coagulant was used to remove turbidity, chemical oxygen demand (COD), and zeta potential. The formed adsorbent was used to remove crystal violet (CV). Coagulation-flocculation experiments were carried out in a jar test to evaluate the performance of the coagulant in powder and extract form. The use of pine cone powder (PCP), extract using NaCl (PC-NaCl), and extract using DW (PC-DW) resulted in turbidity reductions of 96%, 94%, and 98%, respectively. For the residue recovered after extraction, a CV removal percentage of 99.9% was achieved at the optimal conditions of pH 10, CV concentration of 20 mg/L, adsorbent dose of 20 mg/L, and contact time of 120 min, as determined using the Box–Behnken design (BBD). Furthermore, all the effects were significant in the process of the CV phase adsorption on the bio-adsorbent. The model designed for optimal design fit the experimental data well, with a coefficient of determination, R2, of 0.965 and an Adj-R2 of 0.926. The p-value of this model was 0.000, which indicated that the model was very significant. This confirmed the effectiveness of the bio-adsorbent in removing dyes from water. Full article
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18 pages, 4984 KiB  
Article
Adsorption of Sunscreen Compounds from Wastewater Using Commercial Activated Carbon: Detailed Kinetic and Thermodynamic Analyses
by Stefania Gheorghe, Vasile Ion Iancu, Ioana Alexandra Ionescu, Florinela Pirvu, Iuliana Claudia Paun, Luoana Florentina Pascu and Florentina Laura Chiriac
Water 2023, 15(23), 4190; https://doi.org/10.3390/w15234190 - 4 Dec 2023
Cited by 2 | Viewed by 1740
Abstract
Sunscreen compounds are one of the most toxic substances detected in the aqueous environment. However, these molecules are continuously utilized in a various range of products to provide protection against UV radiation. The removal of three sunscreen compounds, 4-hydroxybenzophenone (4-HBP), 2,4-dihydroxybenzophenone [...] Read more.
Sunscreen compounds are one of the most toxic substances detected in the aqueous environment. However, these molecules are continuously utilized in a various range of products to provide protection against UV radiation. The removal of three sunscreen compounds, 4-hydroxybenzophenone (4-HBP), 2,4-dihydroxybenzophenone (BP-1) and oxybenzone (BP-3), by commercial activated carbon (AC) was investigated using batch adsorption experiments. Different operational characteristics, such as adsorbent dosing, interaction time, solution pH and starting sunscreen compound concentration, were studied. The adsorption capacity of the AC material was assessed using a liquid chromatograph associated with a mass spectrometer detector (LC–MS/MS). Two isotherm models were utilized to explained the target compound adsorption phenomenon (Langmuir and Freundlich), while pseudo-first and -second kinetic orders and thermodynamics were utilized to examine the adsorption mechanism. The maximum adsorption capacities determined from the Langmuir isotherms were established as 43.8 mg/g for 4-HBP, 48.8 mg/g for BP-3 and 41.1 mg/g for BP-1. The thermodynamic parameters revealed the following: a negative ΔG° (<20 KJ/mol) and ΔH° and a positive ΔS° of the targeted sunscreen compounds adsorbed onto AC suggest a spontaneous and exothermic adsorption process, favored by lower temperature, proving that the physical sorption mechanism prevailed. Effective adsorption of 4-HBP, BP-3 and BP-1 from real wastewater samples proved the viability of sunscreen compound removal using commercial AC material. This paper offers promising results on a sustainable, economical and environmentally friendly method for removal of ubiquitous sunscreen compounds from wastewater, as a possible enhancement of treatment processes. Full article
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17 pages, 4483 KiB  
Article
Modified Lignocellulosic Waste for the Amelioration of Water Quality: Adsorptive Removal of Congo Red and Nitrate Using Modified Poplar Sawdust
by Natalija Velić, Marija Stjepanović, Stefan Pavlović, Saeed Bagherifam, Predrag Banković and Nataša Jović-Jovičić
Water 2023, 15(21), 3776; https://doi.org/10.3390/w15213776 - 28 Oct 2023
Cited by 3 | Viewed by 1685
Abstract
Since the synthetic dye Congo red and nitrate are notorious contributors to water pollution due to their persistent and potentially toxic nature, it is necessary to develop new efficient methods to remove them from water bodies. Native lignocellulosic materials as biosorbents are mostly [...] Read more.
Since the synthetic dye Congo red and nitrate are notorious contributors to water pollution due to their persistent and potentially toxic nature, it is necessary to develop new efficient methods to remove them from water bodies. Native lignocellulosic materials as biosorbents are mostly inferior, i.e., the adsorption capacities of native materials are lower. Therefore, attempts have been made to improve the adsorption capacities of such materials by physical and/or chemical methods, including the production of biochar. In this study, adsorptive removal was investigated using a novel biosorbent (mPWS) obtained by modifying poplar (waste) sawdust through quaternisation. The characterisation of mPWS included SEM/EDX, FTIR, and MIP analysis. The adsorption of CR and nitrate onto mPWS was studied in a batch system, as a function of contact time (1–240 min), biosorbent concentration (1–8 g·dm−3), and initial adsorbate concentration (25–200 mg·dm−3). In all experiments, a high removal of both adsorbates, from 60 to over 90%, was achieved. Langmuir and Freundlich adsorption isotherm models were used in order to describe equilibrium adsorption data, while pseudo-first-order and pseudo-second-order kinetic models, and the intraparticle diffusion model, were used to describe possible adsorption mechanisms. The Langmuir model fit the adsorption data of CR well, while the nitrate adsorption process was better interpreted with the Freundlich isotherm model. The kinetics data for both CR and nitrate agreed with the pseudo-second-order kinetics model, while analysis using the intraparticle diffusion model indicated two rate-limiting steps during the adsorption process. Based on the results, it can be concluded that the tested novel biosorbent can be effectively used for the removal of CR and nitrate from water (with its adsorption capacities being 70.3 mg·g−1 and 43.6 mg·g−1, respectively). Full article
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29 pages, 5940 KiB  
Article
Green Synthesis of Surface Modified Biochar for Simultaneous Removal of Steroidal Hormones and Heavy Metals from Wastewater: Optimisation by Central Composite Design
by Sefiu Olaitan Amusat, Temesgen Girma Kebede, Edward Ndumiso Nxumalo, Simiso Dube and Mathew Muzi Nindi
Water 2023, 15(20), 3703; https://doi.org/10.3390/w15203703 - 23 Oct 2023
Cited by 1 | Viewed by 2678
Abstract
The modification of pristine biochar derived from the waste of sweet prickly pear using the green modification method to produce nano-sized biochar (nanobiochar) for the removal of steroidal hormones and heavy metals from water and wastewater is reported in this study. Based on [...] Read more.
The modification of pristine biochar derived from the waste of sweet prickly pear using the green modification method to produce nano-sized biochar (nanobiochar) for the removal of steroidal hormones and heavy metals from water and wastewater is reported in this study. Based on the characterisation results using FTIR, Raman spectroscopy, and XPS, the material had (COOH), (C=O), and (OH) functional groups typical of graphitic amorphous carbon. The SEM-EDS and XRD results showed that the material was mesoporous and amorphous in nature. The BET analysis results revealed that the surface area significantly increased from 220.1 m2/g to 354.6 m2/g after the modification of the pristine biochar. Based on the TGA-DSC results, the material was thermally stable up to 550 °C. A complete factorial experimental design using Minitab 21 Statistical Software (version 18.1) was employed to optimise the experimental adsorption conditions. The F-values and p-values for the lack-of-fit of the model showed the acceptability and significance of the ANOVA model. The Freundlich adsorption isotherm was found to provide a better fit for the steroid adsorption data than the Langmuir adsorption isotherm, with moderate values of R2 ≥ 0.92 for Langmuir and R2 ≥ 0.95 for Freundlich, as well as maximum adsorption capacities of 14.53 mg/g, 10.58 mg/g, 12.50 mg/g, 5.73 mg/g, 5.63 mg/g, and 9.75 mg/g obtained for estriol, α-oestradiol, β-oestradiol, testosterone, progesterone, and bisphenol A. Freundlich R2 values were lower than Langmuir R2 values for metal adsorption, with maximum adsorption capacities of 8.58 mg/g, 4.15 mg/g, and 6.95 mg/g obtained for nickel, cadmium, and lead, respectively. The maximum percentage of removal for effluents and influents was between 84–89% and 78–86% for steroid hormones and heavy metals, respectively. The highest removal percentage between 90–95% was obtained for spiked ultrapure water for both steroid hormones and heavy metals. The material exhibited a removal percentage up to 60% after the first four cycles. Full article
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20 pages, 5868 KiB  
Article
Removal of Pharmaceuticals from Water Using Laccase Immobilized on Orange Peels Waste-Derived Activated Carbon
by Osamah J. Al-sareji, Mohammed Alaa Abdulzahra, Thaer Shafi Hussein, Ahmed S. Shlakaa, Mustafa M. Karhib, Mónika Meiczinger, Ruqayah Ali Grmasha, Raed A. Al-Juboori, Viola Somogyi, Endre Domokos, Ibijoke Idowu, Manolia Andredaki and Khalid S. Hashim
Water 2023, 15(19), 3437; https://doi.org/10.3390/w15193437 - 29 Sep 2023
Cited by 9 | Viewed by 2554
Abstract
The ongoing discharge of containments into the environment has raised concerns about the potential harm they pose to various organisms. In the framework of eliminating pharmaceutical chemicals from aqueous solutions, enzymatic degradation by laccase is an environmentally friendly option. In this investigation, laccase [...] Read more.
The ongoing discharge of containments into the environment has raised concerns about the potential harm they pose to various organisms. In the framework of eliminating pharmaceutical chemicals from aqueous solutions, enzymatic degradation by laccase is an environmentally friendly option. In this investigation, laccase immobilized on biochar derived from agricultural waste (orange peels, OPs) was used for the first time to remove carbamazepine and diclofenac from aqueous media. Different characterizations, such as Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDS), X-Ray diffraction (XRD), specific surface area (SBET), Boehm titration, proximate and ultimate analysis, as well as the point of zero-charge (pHPZC) analysis, were used in this study. The immobilization of laccase results in enhanced stability with respect to storage, temperature, and pH compared to laccase in its free form. The findings showed that the ideal conditions for immobilization were a pH of 4, a temperature of 30 °C, and a laccase concentration of 4.5 mg/mL. These parameters led to an immobilization yield of 63.40%. The stability of laccase immobilized on biochar derived from orange peels (LMOPs) was assessed over a period of 60 days, during which they preserved 60.2% and 47.3% of their initial activities when stored at temperatures of 25 °C and 4 °C, respectively. In contrast, free laccase exhibited lower stability, with only 33.6% and 15.4% of their initial activities maintained under the same storage conditions. Finally, the use of immobilized laccase proved to be effective in eliminating these pollutants in up to five cycles. Upon comparing the two systems, namely LMOPs and modified orange peels (MOPs), it becomes apparent that LMOPs exhibit an estimated 20% improvement in removal efficiency. These results affirmed the viability of activated carbon derived from OPs as a cost-effective option for immobilizing laccase. This approach could potentially be further scaled up to effectively eliminate organic pollutants from water sources. Full article
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17 pages, 2044 KiB  
Article
Optimization of the Preparation Conditions of Aluminum-Impregnated Food Waste Biochar Using RSM with an MLP and Its Application in Phosphate Removal
by Jin-Kyu Kang, Khonekeo Kingkhambang, Chang-Gu Lee and Seong-Jik Park
Water 2023, 15(16), 2997; https://doi.org/10.3390/w15162997 - 20 Aug 2023
Cited by 1 | Viewed by 2920
Abstract
Phosphorus is an essential macroelement in plant growth and the human body, but excessive water enrichment with phosphorus is a global threat to water quality. To address this problem, the development of an efficient, affordable adsorbent for use in removing large amounts of [...] Read more.
Phosphorus is an essential macroelement in plant growth and the human body, but excessive water enrichment with phosphorus is a global threat to water quality. To address this problem, the development of an efficient, affordable adsorbent for use in removing large amounts of phosphorus from eutrophic water is necessary. Food-waste-based adsorbents offer a sustainable solution because they utilize waste as a valuable resource. This study explored the use of food waste biochar as a novel adsorbent with additional aluminum impregnation (Al–FWB) to enhance its phosphate adsorption capacity. This study employed response surface methodology (RSM) to optimize the synthetic conditions of the Al–FWB with the highest phosphate adsorption capacity. To enhance the identification of the optimal conditions using RSM, this study employed quadratic equations and a multi-layer perceptron (MLP). The pyrolysis temperature and Al concentration significantly (p < 0.05) affected the adsorption capacity of the AL–FWB. The optimal conditions for the preparation of the AL–FWB were a pyrolysis temperature, duration, and Al concentration of 300 °C, 0.5 h, and 6%, respectively, based on the quadratic equation and MLP models. X-ray photoelectron spectroscopy revealed that phosphate was adsorbed on the surface of the AL–FWB via the formation of AlPO4. The optimized AL–FWB (Opt-AL–FWB) removed 99.6% of the phosphate and displayed a maximum phosphate adsorption capacity of 197.8 mg/g, which is comparable to those reported in previous studies. Additionally, the phosphate adsorption capacity of the Opt-AL–FWB was independent of the pH of the solution, and the presence of 10 mM SO42– decreased its adsorption capacity by 15.5%. The use of the Opt-AL–FWB as an adsorbent provides not only efficient phosphate removal but also green, economical food waste reusability. In summary, this study demonstrates the potential of AL–FWB as an effective, sustainable, and affordable adsorbent for use in phosphate removal from contaminated water. Full article
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12 pages, 3365 KiB  
Communication
Glyphosate Removal from Water Using Biochar Based Coffee Husk Loaded Fe3O4
by Arestha Leo Lita, Endar Hidayat, Nur Maisarah Mohamad Sarbani, Hiroyuki Harada, Seiichiro Yonemura, Yoshiharu Mitoma, Herviyanti and Gusmini
Water 2023, 15(16), 2945; https://doi.org/10.3390/w15162945 - 15 Aug 2023
Cited by 7 | Viewed by 2195
Abstract
Glyphosate is an herbicide that is usually used by farmers and is considered harmful to the environment in excess amounts. To address these issues, coffee-husk-biochar-loaded Fe3O4 (CHB- Fe3O4) was used as an adsorbent to remove glyphosate [...] Read more.
Glyphosate is an herbicide that is usually used by farmers and is considered harmful to the environment in excess amounts. To address these issues, coffee-husk-biochar-loaded Fe3O4 (CHB- Fe3O4) was used as an adsorbent to remove glyphosate from water. CHB-Fe3O4 characteristics such as pHpzc, FTIR, and SEM were measured to understand the properties of this adsorbent. The best conditions for glyphosate removal by CHB-Fe3O4 were obtained at pH 2.0, where the adsorption capacity and percentage removal are 22.44 mg/g and 99.64%, respectively, after 4 h of adsorption. The Freundlich model provided the best fit for the adsorption isotherm, demonstrating multilayer sorption. The most effective model for characterizing the adsorption kinetics was the pseudo-second-order model with a chemical adsorption mechanism. The desorption studies found that the use of 0.1 M NaOH was the best concentration to effectively desorb glyphosate with a desorption percentage of 69.4%. This indicates that CHB- Fe3O4 is a feasible adsorbent for glyphosate removal from water. Full article
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19 pages, 5379 KiB  
Article
Ciprofloxacin Adsorption onto a Smectite–Chitosan-Derived Nanocomposite Obtained by Hydrothermal Synthesis
by Marija Ajduković, Gordana Stevanović, Sanja Marinović, Zorica Mojović, Predrag Banković, Katarina Radulović and Nataša Jović-Jovičić
Water 2023, 15(14), 2608; https://doi.org/10.3390/w15142608 - 18 Jul 2023
Cited by 6 | Viewed by 1963
Abstract
The employment of compounds obtained from natural sources to produce adsorbents and their application in the elimination of antibiotics from industrial effluents have gained significant attention because of their low production cost and sustainability. Herein, chitosan (biopolymer) and smectite (abundant clay mineral) were [...] Read more.
The employment of compounds obtained from natural sources to produce adsorbents and their application in the elimination of antibiotics from industrial effluents have gained significant attention because of their low production cost and sustainability. Herein, chitosan (biopolymer) and smectite (abundant clay mineral) were used for the low-cost and eco-friendly synthesis of a new type of adsorbent. A low-energy-consumption hydrothermal process was applied to the synthesis of the chitosan-derived carbon–smectite nanocomposite with cobalt (H_Co/C-S). The produced nanocomposite was characterized using elemental analysis, ICP-OES, XRPD, low-temperature N2 adsorption–desorption isotherms, FTIR analysis, and point of zero charge. H_Co/C-S (SBET = 0.73 m2 g−1, d001 = 1.40 nm, pHPZC = 5.3) was evaluated as a ciprofloxacin adsorbent in aqueous solution. Experimental data were fitted with different kinetic models and interpreted by selected adsorption isotherms. The pseudo-second-order model was found to be the most appropriate, while ciprofloxacin adsorption onto H_Co/C-S was best described by the Redlich–Peterson isotherm (R2 = 0.985). The maximum adsorption capacity of H_Co/C-S, according to the Langmuir isotherm (R2 = 0.977), was 72.3 mg g−1. Desorption and thermodynamic studies were performed. The obtained results indicated that the new hierarchically designed H_Co/C-S has promising potential to be further tested for application in real wastewater treatment. Full article
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18 pages, 4536 KiB  
Article
The Removal of Phosphate from Aqueous Solutions by Sepiolite/ZrO2 Composites: Adsorption Behavior and Mechanism
by Željka Milovanović, Slavica Lazarević, Ivona Janković-Častvan, Željko Radovanović, Slobodan Cvetković, Đorđe Janaćković and Rada Petrović
Water 2023, 15(13), 2376; https://doi.org/10.3390/w15132376 - 27 Jun 2023
Cited by 5 | Viewed by 1598
Abstract
The sepiolite/ZrO2 composites were prepared by sepiolite (Sep) modification with zirconium propoxide in toluene at room temperature for 24 h (Sep–ZrI) or 95 °C for 4 h (sample Sep–ZrII). The efficiency of the obtained composites for the removal of phosphate from aqueous [...] Read more.
The sepiolite/ZrO2 composites were prepared by sepiolite (Sep) modification with zirconium propoxide in toluene at room temperature for 24 h (Sep–ZrI) or 95 °C for 4 h (sample Sep–ZrII). The efficiency of the obtained composites for the removal of phosphate from aqueous solutions at initial pH = 4 and pH = 8 was investigated. Characterization of the samples shows that synthesis at a higher temperature for a shorter time provides a slightly higher content of amorphous Zr phase, which is deposited on the sepiolite fibers as a thin layer and agglomerated nanoparticles. Compared to Sep, the composites have a lower point of zero charge and higher specific surface area and pore volume. The adsorption kinetics follow the pseudo second-order model. The adsorption capacities of the composites are approximately the same at both initial pH and higher at initial pH = 4 than at pH = 8. The XPS and ATR-FTIR of Sep–ZrI before and after adsorption identifies the formation of inner-sphere complexes as the mechanism of phosphate adsorption. The slow release during desorption with NaOH solution confirms the strong bonds of the phosphates with the surface of the composites. Full article
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Review

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18 pages, 967 KiB  
Review
Lignocellulose-Based Biosorbents for the Removal of Contaminants of Emerging Concern (CECs) from Water: A Review
by Vesna Vasić, Dragana Kukić, Marina Šćiban, Nataša Đurišić-Mladenović, Natalija Velić, Biljana Pajin, João Crespo, Marinella Farre and Zita Šereš
Water 2023, 15(10), 1853; https://doi.org/10.3390/w15101853 - 13 May 2023
Cited by 13 | Viewed by 3740
Abstract
Contaminants of emerging concern (CECs) are chemicals or materials that are not under current regulation but there are increasing concerns about their possible occurrence in the environment because of their potential threat to human and environmental health, with wastewater perceived as their primary [...] Read more.
Contaminants of emerging concern (CECs) are chemicals or materials that are not under current regulation but there are increasing concerns about their possible occurrence in the environment because of their potential threat to human and environmental health, with wastewater perceived as their primary source. Although various techniques for their removal from water have been studied, it should be emphasized that the choice should also consider the use of resources and energy within the removal processes, which must be minimized to avoid additional carbon footprints and environmental impact. In this context, the use of biomass-based sorbents might represent a cost-effective and environmentally friendly approach for the removal of CECs from water because they are based on preferably local renewable resources with lower negative impacts on the global carbon cycle through greenhouse gas emissions than the conventional nonrenewable ones. This paper provides an overview of the studies dealing with the application of such so-called biosorbents for the removal of CECs from water and discusses the use of their different forms: sorbents after a minimal pretreatment of the original lignocellulosic biomass; sorbents extracted from lignocellulosic biomass and/or modified; and biochar-based sorbents obtained after thermochemical conversion of biomass. It explains possible modifications of biosorbents and discusses the efficiency of various biosorbents for the removal of selected emerging compounds that belong to the classes of pharmaceuticals, personal care products, and pesticides and compares the adsorption capacities, kinetic models, and mechanisms reported in the relevant literature. Biochar-based sorption has been studied more often if compared to other considered biosorbents. In some cases, removal efficiencies of contaminants greater than 90% were achieved, but nonetheless a wide range of efficiencies for different CECs indicates that for successful simultaneous multicompound removal, a combination of different processes seems to be a more appropriate approach than the stand-alone use of biosorbents. Finally, this review discusses the reasons behind the limited commercial application of the considered biosorbents and provides directions for possible further research, in particular the use of spent biosorbents from a perspective of circular systems. Full article
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