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•A comprehensive overview of AI applications in water treatment is presented.•The potential of AI in predicting the performances of adsorption processes are portrayed in detail.•The ...major challenges in AI applications are accentuated.•A roadmap for future research is suggested.
Artificial intelligence (AI) has emerged as a powerful tool to resolve real-world problems and has gained tremendous attention due to its applications in various fields. In recent years, AI techniques have also been employed in water treatment and desalination to optimize the process and to offer practical solutions to water pollution and water scarcity. Applications of AI is also expected to reduce the operational expenditures of the water treatment process by decreasing the cost and optimizing chemicals usage. This review summarizes various AI techniques and their applications in water treatment with a focus on the adsorption of pollutants. Numerous AI models have successfully predicted the performance of different adsorbents for the removal of numerous pollutants from water. This review also highlighted some challenges and research gap concerning applications of AI in water treatment. Despite several advantages offered by AI, there some limitations that hindered the widespread applications of these techniques in real water treatment systems. The availability and selection of data, poor reproducibility, less evidence of applications in real water treatment are some of the key challenges that need to be addressed. Recommendations are made to ensure the successful applications of AI in future water-related technologies. This review is beneficial for environmental researchers, engineers, students, and all stakeholders in the water industry.
In this study, desorption of Methylene blue (MB) dye from brown macroalga, Nizamuddinia zanardinii was investigated. Batch experiments were conducted to determine the effects of various operating ...parameters namely, the effect of seventeen different eluents, eluents concentrations, dye saturated alga weight, different HCl:1-butanol ratios, different particle sizes, different alga mass washing modes (after sorption experiment), initial dye concentration in the sorption experiment and contact time on the desorption efficiency of MB dye from brown macroalga. Among the seventeen eluents tested, hydrochloric acid (HCl) was found to be the most effective eluent for dye desorption. The mixture of 1 M HCl (25%):1 M 1-butanol (75%) was found to increase the dye desorption efficiency up to 63.67 ± 1.67%. Dye desorption percentage increased by increasing the alga particle sizes from <75 μm to >250 μm. The highest and lowest desorption efficiencies were attained by wet and dry masses after water washing by shaker, respectively. Both isotherm and kinetic data were obtained and fitted very well with the Sips isotherm model and pseudo-second-order kinetic model. After five sorption/desorption cycles, the dye sorption efficiency decreased from 96.99 ± 0.90% to 48.16 ± 1.98%, and the dye desorption efficiency decreased from 68.70 ± 2.03% to 46.83 ± 1.49%. Overall, this study has demonstrated that brown macroalga is a promising sorbent for the removal of MB dye from aqueous solutions.
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•Desorption of Methylene blue dye onto brown marine macroalga was studied.•Effects of different operating variables were examined during desorption.•Dye desorption percentage increased by increasing the alga particle sizes.•After five cycles, the desorption efficiency decreased from 68.7% to 46.8%.
In this study, mesoporous carbonated TiO2 nanoparticles were synthesized by sol-gel route using a complex Ti(OH2)63+·3Cl− and a modifying agent Na2CO3 and used as an adsorbents for Sr(II) removal ...from aqueous medium. The characterization of nanoadsorbents was accomplished using XRD, SEM, EDS, TEM, TG-DTG-DTA, IR, BET, pHPZC analyses. It was found that the sizes of carbonated TiO2 nanoparticles was ~4 nm. The presence of mononuclear bidentate carbonate groups on the titania surface was approved by IR spectroscopy. The kinetic data was analyzed by pseudo-first-order, pseudo-second-order, Elovich, and an intraparticle diffusion models. The adsorption isotherms were fitted by using Langmuir, Freundlich, and Dubinin–Radushkevich models. The fittings show that the pseudo-second-order kinetics and Langmuir isotherm are suitable models for the adsorption process. The sample with 4% (wt.) of carbonate groups showed the best adsorption performance towards Sr(II) cations. The mesoporous carbonated samples demonstrated a higher adsorption capacity for strontium ions than the basic TiO2. The adsorption capacities of modified 2C-TiO2, 4C-TiO2 and 8C-TiO2 samples were 170.4, 204.4, 190.8 mg/g respectively, while it was 70.9 mg/g for the unmodified TiO2 towards Sr(II). Higher removal of Sr(II) was observed in the alkaline medium due to the formation of SrОН+ cations. A mechanism for Sr(II) adsorption was described and the number of chemosorbed ≡Ті(О2СО) groups and active adsorption centers onto unmodified and modified TiO2 surface were calculated. The titania adsorbents have high reusability and retain their adsorption capacity during five adsorption-desorption cycles. The presented results indicated that the mesoporous carbonated adsorbents were appropriate materials for the removal of Sr(II) from aqueous medium.
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•A new mesoporous TiO2 with chemosorbed carbonate groups has been synthesized.•Sr(II) successfully removed using a carbonated mesoporous titania•Sr(II) removal capacity of the 4C-TiO2 is 204.4mg/g at natural pH•Titanocarbonate groups provide the formation of surface acidic centers.
In the present study, Fe3O4@AMCA-MIL-53(Al) nanocomposite was utilized for the adsorptive removal of highly toxic MB and MG dyes from aqueous environment. The batch adsorption tests were performed at ...different contact time, pH, Fe3O4@AMCA-MIL-53(Al) dose, initial concentration of dyes and temperature. The maximum adsorption capacity of MB and MG dyes onto of Fe3O4@AMCA-MIL-53(Al) using Langmuir equation was 1.02 and 0.90 m mol/g, respectively. The isotherm and kinetic studies revealed that adsorption data were well fitted to Langmuir isotherm and pseudo-first-order kinetics models. Various thermodynamic parameters were also calculated and interpreted. The positive and negative values of ΔH° and ΔG° indicated that the adsorption was endothermic and spontaneous, respectively. The adsorptive binding of MB and MG on Fe3O4@AMCA-MIL53(Al) nanocomposite was directed by carboxylate and amide groups through electrostatic interaction, π−π interaction and hydrogen bonding. The desorption of both dyes from Fe3O4@AMCA-MIL-53(Al) was also performed using mixed solution of 0.01 M HCl/ethanol. Thus, we conclude that the Fe3O4@AMCA-MIL-53(Al) was an outstanding material for the removal of dyes from aqueous environment.
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•Fe3O4@AMCA-MIL-53(Al) was used for the removal MB and MG dyes from aqueous medium.•The overall removal of MB and MG dyes (25 mg/L) from water reached more than 88%.•Adsorption capacity was increased with increase in temperature.•Maximum adsorption capacity was higher than those of most reported adsorbents.
Polluted soil and water impact the quality of food and nutrients of human and animal biota. Soil and water are mainly polluted by effluent discharges from industries, which are broadly classified ...into metallic and nonmetallic pollutant-bearing effluents. In order to tackle this problem, a plant-based technology called phytoremediation is used to clean contaminated lands. Phytoremediation is based upon several processes such as phytodegradation, phytovolatilization, phytoaccumulation and phytoextraction. These methods are efficient, eco-friendly and economic. This paper reviews the methods and mechanisms involved in phytoremediation of heavy metals, and enhancement processes.
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•Toxicity of arsenic and its treatment was discussed.•The review comprises the application of nanomaterials in arsenic water treatment.•The recent advances in arsenic water treatment ...using nanomaterials were explicated.•Described the improvements for adsorption of arsenic using latest nanomaterials.•Interaction mechanism between arsenic and nanomaterials was elucidated.
This review discusses the brief of health problem associated with the arsenic exposure found in drinking water. This review also discusses the shortcomings associated with the traditional methods, advantages with adsorption process and the new approaches towards the advance and effective techniques. The novelty of present study is a collection of latest literature and reports which comprises the latest advances made in the nanoparticles and nano-composites for the efficient removal of arsenic from aqueous medium. The mechanism of interaction of arsenic and nanomaterials surface is discussed in this novel review. The latest and novel approaches towards avoiding the preoxidation step for arsenite removal using oxidants is also highlighted, and the large numbers of nanomaterials having the photo catalytic properties and functionalities for simultaneous oxidation of arsenite to arsenate and adsorption of both forms, is also deliberated. No previous literatures have discussed the detail of oxidation of arsenite to arsenate using the nanomaterials having photocatalytic activities. Overall, this review highlights and provides an overview, advantages and features of the newly developed nanomaterials comprising virgin zero valent metallic nanoparticles, metal oxides, metal doped oxides, binary metal oxides, mixed metal oxides, functionalized metal oxides and organic-inorganic nanocomposites for arsenic removal. The comparative evaluation of cited nanomaterials and low-cost, and others micro/nano-sized adsorbent has also been also comprised. The disadvantages associated with the existing technology are deeply highlighted and future development and prospects have been discussed in depth. Therefore, this review article will definitely contribute a great role to the researches by developing the advanced materials to remove all shortcomings associated with the existing technologies.
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•Fe3O4@TATS@ATA was prepared and applied for the adsorptive removal of Pb(II) metal.•The maximum adsorption capacity for Pb(II) was 205.2 mg/g at pH 5.7 and 298 K.•Thermodynamic ...confirmed the spontaneous and exothermic adsorption.•The nanocomposite adsorbent was ease of separate and reusability.
Herein, a novel nanocomposite (Fe3O4@TATS@ATA) was prepared and used for adsorptive removal of Pb(II) ions from aqueous environment. The magnetic nanocomposite (Fe3O4@TATS@ATA) was characterized using FTIR, TEM, SEM, EDX, element mapping analysis (EMA), TGA analysis, XRD patterns, VSM, BET analysis, XPS spectrum, and zeta potential. The FTIR study confirmed the modification of Fe3O4 nanoparticles with triaminetriethoxysilane and 2-aminoterephthalic acid while XPS analysis (with peaks at 283.6, 285.1, 286.3, 284.5.0, 288.4 eV) displayed the presence of CSi, CN, OCNH, CC/CC and OCO functional groups, respectively on Fe3O4@TATS@ATA. The BET surface area, average pore size, pore volume and magnetization saturation for Fe3O4@TATS@ATA were found to be 114 m2/g, 6.4 nm, 0.054 cm−3/g, and 22 emu/g, respectively. The adsorption isotherm data showed that Pb(II) adsorption onto Fe3O4@TATS@ATA fitted to Langmuir and Dubinin–Raduskevich isotherm model due to better R2 value which was greater than 0.9 and qm of Pb(II) was 205.2 mg/g at pH 5.7 in 150 min. Adsorption kinetics data displayed that Pb(II) adsorption onto Fe3O4@TATS@ATA was fitted to the pseudo-second-order and Elovich kinetic models. Thermodynamic outcomes exhibited the exothermic and spontaneous nature of adsorption. Results showed that Fe3O4@TATS@ATA nanocomposite was promising material for efficient removal of toxic Pb(II) from aqueous environment.
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•Ligand anchoring facial adsorbent was efficient for Co(II) ion detection and removal.•The higher sorption capacity of the Co(II) ions was observed at higher pH regions.•Maximizing ...the Co(II) ion capturing from solution by optimizing the conditions.•This adsorbent provided a simple and effective treatment for Co(II) containing water.
Ligand anchored functional nanomaterials are increasingly gaining interest as efficient materials for various types of toxic pollutants. In this study, the organic ligand of N,N′di(3-carboxysalicylidene)-3,4diamino-5-hydroxypyrazole was densely anchored onto the mesoporous silica by the building-block approach as facial adsorbent, characterized and then examined for the cobalt (Co(II)) ion detection and removal from aqueous solutions. The fixed-time approach was employed for analytical signal measurement in the detection operation. At optimum conditions, the calibration curve was linear in the range of 0.002–0.10mg/L Co(II) and the limit of detection was also achieved at 0.24μg/L. Moreover, the diverse ions did not show any significant absorbance intensity. Therefore, the established facial adsorbent provided a simple, rapid, cheap and sensitive method for Co(II) detection and could be used to detect Co(II) ions in the environment. This study also examined the possibility of using facial adsorbent to remove low concentrations of Co(II) ions from water solution. The sorption capacity was significantly affected by solution acidity, contact time and initial Co(II) ion concentration. The higher sorption capacity of the Co(II) ions was observed at higher pH regions. The sorption isotherms fit the Langmuir sorption model well and the maximum Co(II) ion sorption capacity was 157.73mg/g. The effective eluent of 0.20M HCl was used to elute the Co(II) from the facial adsorbent, and the adsorbent was simultaneously regenerated into the initial form after rinsing with water. The elution and regeneration showed that the adsorbent could be reused without significant losses of its initial properties even after 8 sorption–elution–reuse cycles. Therefore, the facial adsorbent could be used as a promising adsorbent for fast Co(II) ion detection and removal and might provide a simple and effective method for the treatment of water containing Co(II).
We aimed to obtain magnesium/iron (Mg/Fe)-layered double hydroxides (LDHs) nanoparticles-immobilized on waste foundry sand-a byproduct of the metal casting industry. XRD and FT-IR tests were applied ...to characterize the prepared sorbent. The results revealed that a new peak reflected LDHs nanoparticles. In addition, SEM-EDS mapping confirmed that the coating process was appropriate. Sorption tests for the interaction of this sorbent with an aqueous solution contaminated with Congo red dye revealed the efficacy of this material where the maximum adsorption capacity reached approximately 9127.08 mg/g. The pseudo-first-order and pseudo-second-order kinetic models helped to describe the sorption measurements, indicating that the physical and chemical forces governed the removal process.
Increased request for metal and metal oxide nanoparticles nanoparticles has led to their large-scale production using high-energy methods with various toxic solvents. This cause environmental ...contamination, thus eco-friendly “green” synthesis methods has become necessary. An alternative way to synthesize metal nanoparticles includes using bioresources, such as plants and plant products, bacteria, fungi, yeast, algae, etc. “Green” synthesis has low toxicity, is safe for human health and environment compared to other methods, meaning it is the best approach for obtaining metal and metal oxide nanoparticles. This review reveals 12 principles of “green” chemistry and examples of biological components suitable for “green” synthesis, as well as modern scientific research of eco-friendly synthesis methods of magnetic and metal nanoparticles. Particularly, using extracts of green tea, fruits, roots, leaves, etc., to obtain Fe3O4 NPs. The various precursors as egg white (albumen), leaf and fruit extracts, etc., can be used for the „green” synthesis of spinel magnetic NPs. “Green” nanoparticles are being widely used as antimicrobials, photocatalysts and adsorbents. “Green” magnetic nanoparticles demonstrate low toxicity and high biocompatibility, which allows for their biomedical application, especially for targeted drug delivery, contrast imaging and magnetic hyperthermia applications. The synthesis of silver, gold, platinum and palladium nanoparticles using extracts from fungi, red algae, fruits, etc., has been described.
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