Experimental analysis and prediction of radionuclide solubility using machine learning models: Effects of organic complexing agents.

Radioactive wastes contain organic complexing agents that can form complexes with radionuclides and enhance the solubility of these radionuclides, increasing the mobility of radionuclides over great distances from a radioactive waste repository. In this study, four radionuclides (cobalt, strontium, iodine, and uranium) and three organic complexing agents (ethylenediaminetetraacetic acid, nitrilotriacetic acid, and iso-saccharic acid) were selected, and the solubility of these radionuclides was assessed under realistic environmental conditions such as different pHs (7, 9, 11, and 13), temperatures (10 °C, 20 °C, and 40 °C), and organic complexing agent concentrations (10-5-10-2 M). A total of 720 datasets were generated from solubility batch experiments. Four supervised machine learning models such as the Gaussian process regression (GPR), ensemble-boosted trees, artificial neural networks, and support vector machine were developed for predicting the radionuclide solubility. Each ML model was optimized using Bayesian optimization algorithm. The GPR evolved as a robust model that provided accurate predictions within the underlying solubility patterns by capturing the intricate relationships of the independent parameters of the dataset. At an uncertainty level of 95%, both the experimental results and GPR simulated estimations were closely correlated, confirming the suitability of the GPR model for future explorations.

The characteristics of elderly suicidal attempters in the emergency department in Korea: a retrospective study.

BACKGROUND: Although Korea ranks first in the suicide rate of elderly individuals, there is limited research on those who attempt suicide, with preventive measures largely based on population-based studies. We compared the demographic and clinical characteristics of elderly individuals who attempted suicide with those of younger adults who visited the emergency department after suicide attempts and identified the factors associated with lethality in the former group. METHODS: Individuals who visited the emergency department after a suicide attempt from April 1, 2017, to January 31, 2020, were included. Participants were classified into two groups according to age (elderly, ≥65 years; adult, 18-64 years). Among the 779 adult patients, 123 were elderly. We conducted a chi-square test to compare the demographic and clinical features between these groups and a logistic regression analysis to identify the risk factors for lethality in the elderly group. RESULTS: Most elderly participants were men, with no prior psychiatric history or suicide attempts, and had a higher prevalence of underlying medical conditions and attributed their attempts to physical illnesses. Being sober and planning suicide occurred more frequently in this group. In the elderly group, factors that increased the mortality rate were biological male sex (p<0.05), being accompanied by family members (p<0.05), and poisoning as a suicide method (p<0.01). CONCLUSION: Suicide attempts in elderly individuals have different characteristics from those in younger adults and are associated with physical illness. Suicides in the former group are unpredictable, deliberate, and fatal. Therefore, tailored prevention and intervention strategies addressing the characteristics of those who are elderly and attempt suicide are required.

Sodium-alginate-laden MXene and MOF systems and their composite hydrogel beads for batch and fixed-bed adsorption of naproxen with electrochemical regeneration.

Sodium alginate (SA)-laden two-dimensional (2D) Ti3C2Tx MXene (MX) and MIL-101(Fe) (a type of metal-organic framework (MOF)) composites were prepared and used for the removal of naproxen (NPX), following the adsorption and electrochemical regeneration processes. The fixed-bed adsorption column studies were also conducted to study the process of removal of NPX by hydrogels. The number of interactions via which the MX-embedded SA (MX@SA) could adsorb NPX was higher than the number of pathways associated with NPX adsorption on the MIL-101(Fe)-embedded SA (MIL-101(Fe)@SA), and the MX and MIL-101(Fe) composite embedded SA (MX/MIL-101(Fe)@SA). The optimum parameters for the electrochemical regeneration process were determined: charge passed and current density values were 169.3 C g-1 and 10 mA cm-2, respectively, for MX@SA, and the charge passed and current density values were 16.7 C g-1 and 5 mA cm-2, respectively, for both MIL-101(Fe)@SA and MX/MIL-101(Fe)@SA. These parameters enabled excellent regeneration, consistent over multiple adsorption and electrochemical regeneration cycles. The mechanism for the regeneration of the materials was proposed that the regeneration of MX@SA and MIL-101(Fe)@SA involved the indirect electrooxidation process in the presence of OH radicals, and the regeneration of MX/MIL-101(Fe)@SA involved the indirect oxidation process in the presence of active chlorine species.

HSA-ZW800-PEG for Enhanced Optophysical Stability and Tumor Targeting.

Small molecule fluorophores often face challenges such as short blood half-life, limited physicochemical and optical stability, and poor pharmacokinetics. To overcome these limitations, we conjugated the zwitterionic near-infrared fluorophore ZW800-PEG to human serum albumin (HSA), creating HSA-ZW800-PEG. This conjugation notably improves chemical, physical, and optical stability under physiological conditions, addressing issues commonly encountered with small molecules in biological applications. Additionally, the high molecular weight and extinction coefficient of HSA-ZW800-PEG enhances biodistribution and tumor targeting through the enhanced permeability and retention effect. The unique distribution and elimination dynamics, along with the significantly extended blood half-life of HSA-ZW800-PEG, contribute to improved tumor targetability in both subcutaneous and orthotopic xenograft tumor-bearing animal models. This modification not only influences the pharmacokinetic profile, affecting retention time and clearance patterns, but also enhances bioavailability for targeting tissues. Our study guides further development and optimization of targeted imaging agents and drug-delivery systems.

Electrocatalytic oxidation of antidiabetic drug metformin adsorbed on intercalated MXene.

Two-dimensional (2D) Ti3C2Tx transition metal carbide (MXene) nanosheets intercalated with sodium ions (SI-Ti3C2Tx MXene) were used in the adsorption and electrochemical regeneration process for removal of the antidiabetic drug metformin (MF) as a model emerging pollutant. After MF adsorption, SI-Ti3C2Tx MXene oxidized the MF on its surface through its electrocatalytic activity at very low current density and cell potential. For complete oxidation the optimum parameters were 0.525 C g-1, 0.005 mA cm-2, and pH 6 in absence of NaCl or 26.25 C g-1 and 0.5 mA cm-2 in the presence of 2.5 w/v% NaCl. The overall regeneration of SI-Ti3C2Tx is governed by a combined mechanism, i.e., desorption followed by degradation. The degradation mechanism, such as direct electron transfer or indirect oxidation, depends on the applied operating conditions. Thus, the investigation suggests that these 2D sheets are good nanoadsorbents as well as good electrocatalysts and proves their usefulness in practical water-treatment applications.

Buckwheat hull-derived biochar immobilized in alginate beads for the adsorptive removal of cobalt from aqueous solutions.

Buckwheat hull-derived biochar (BHBC) beads were synthesized by immobilizing biochar powder with alginate. Due to their cation-exchange ability, abundant functional groups, microporous structure, and large surface area, BHBC beads were successfully applied for the removal of cobalt from aqueous solution. The adsorption behavior followed pseudo-second-order kinetics and the Langmuir isotherm model showed a better fit to adsorption data than the Freundlich or Temkin isotherm models. The maximum adsorption capacity of BHBC beads was 24.0 mg/g at pH 5, 35 °C, and an initial cobalt concentration of 1.0 g/L, which was higher than those of previously reported natural resource-based adsorbents. In a fixed-bed column study, the effects of operating parameters such as flow rate, bed height, and bed diameter were investigated. Both the Thomas and Yoon-Nelson models were applied to the experimental data to predict the breakthrough curves using nonlinear regression. Overall, BHBC beads can be used as an efficient adsorbent for removal of radioactive cobalt from aqueous solution.

Development of a three-dimensional macroporous sponge biocathode coated with carbon nanotube-MXene composite for high-performance microbial electrosynthesis systems.

Microbial electrosynthesis (MES) is a renewable energy platform capable of reducing the carbon footprint by converting carbon dioxide/bicarbonate to useful chemical commodities. However, the development of feasible electrode structures, inefficient current densities, and the production of unfavorable electrosynthesis products remain a major challenge. To this end, a three-dimensional (3D) macroporous sponge coated with a carbon nanotube/MXene composite (CNT-MXene@Sponge) was evaluated as an MES cathode. The macroporous scaffold, together with intrinsic electrical conductivity, enhanced the charge transfer efficiency and selective microbial enrichment characteristics of the CNT-MXene@Sponge cathode resulted in an average current density of -324 mA m-2, which was substantially higher than that of the uncoated (-100 mA m-2), CNT (-141 mA m-2), and MXene (-214 mA m-2) coated sponge electrode. The uniform 3D structure and abundant active sites of the coated material facilitated mass diffusion and microbial growth, which produced 1.5 orders of magnitude higher butyrate than the uncoated sponge. The high-throughput sequencing results showed the selective enrichment of electrogenic and butyrate-producing phylum, Firmicutes. These results suggest that the MES performance could be enhanced using the collective features of large-pore network structure, such as better conductivity, improved capacitance, and selective microbial enrichment.

Enhanced photocatalytic degradation of bisphenol A by magnetically separable bismuth oxyiodide magnetite nanocomposites under solar light irradiation.

Bismuth oxyiodide/magnetite (BiOI/Fe3O4) nanocomposites were synthesized by a hydrothermal reaction. The synthesized BiOI/Fe3O4 was used to remove bisphenol A (BPA) from an aqueous solution under simulated solar light. The molar ratio of Bi to Fe in BiOI/Fe3O4 significantly affected BPA degradation, with the optimal BiOI/Fe3O4 (2:1) ratio in the composites. Optimum operating conditions such as a catalyst dosage of 1.0 g/L, an initial BPA concentration of 10 mg/L, and pH 7 gave a complete degradation of completely removed BPA within 30 min. The primary reactive oxygen species were verified as superoxide radicals and holes in oxidative species experiments. The magnetic BiOI/Fe3O4 could be easily collected from an aqueous solution by an external magnet, and its reusability was successfully demonstrated through recycling experiments. Furthermore, the derivatives in BiOI/Fe3O4 photocatalytic reactions were investigated, and a possible BPA degradation pathway was proposed. These results show that BiOI/Fe3O4 nanocomposites have great potential for BPA removal from water and wastewater treatment systems.

MXsorption of mercury: Exceptional reductive behavior of titanium carbide/carbonitride MXenes.

Two-dimensional (2D) transition metal carbides and nitrides (MXenes) have drawn considerable attention for application in the field of environmental remediation. In this study, we report the simultaneous reductive-adsorption behavior of Ti3CNTx for toxic metal ion Hg2+ ion in the aqueous phase. 2D Ti3CNTx and Ti3C2Tx MXene nanosheets were synthesized by exfoliation of Ti3AlCN and Ti3AlC2 MAX phases, respectively. Various characteristics analysis confirmed the successful fabrication of MAX phases and their exfoliation into MXenes. The fabricated MXene nanosheets were used to investigate their Hg2+ removal, Hg2+ intercalation, and surface interaction mechanism efficiencies. Both MXenes were found to adsorb and reduce a large amount of Hg2+. Analytical techniques such as X-ray powder diffraction, field emission transmission electron microscopy, zeta-potential analyses, and X-ray photoelectron spectroscopy were used to investigate the material characteristics and structural changes after uptake of Hg2+. The quantitative investigation confirmed the interaction of bimetal and hydroxyl groups with Hg2+ using electrostatic interactions and adsorption-coupled reduction. In addition, both MXenes exhibited extraordinary Hg ion removal capabilities in terms of fast kinetics with an excellent distribution coefficient (KdHg) up to 1.36 × 10+9. Based on batch adsorption results, Ti3C2Tx and Ti3CNTx exhibited removal capacities of 5473.13 and 4606.04 mg/g, respectively, for Hg2+, which are higher than those of previous Hg adsorbents.

MXene-coated biochar as potential biocathode for improved microbial electrosynthesis system.

Microbial electrosynthesis (MES) holds tremendous large scale energy storage potential. By promoting the bioconversion of carbon dioxide (bicarbonate) into useful chemical commodities, this technique utilizes renewable energy and reduces carbon footprint. However, expensive electrode materials, low current densities, and multiple electrosynthesis products are major challenges to this field. To this end, this study examines a multilayered and conductive MXene structure that was coated on a cost-effective biochar substrate and tested as a MES cathode. These results show this coating yielded improved electrical conductivity, increased charge transfer efficiency, and selective microbial enrichment characteristics, resulting in a 2.3-fold increase in cathodic current production in comparison to the uncoated biochar. Moreover, an increase in active sites improved mass transfer and microbial growth, producing 1.7-fold increase in butyrate in comparison to the uncoated control. Considering that electrode attached microbial communities play a major role in final products, microbial community analyses was completed, suggesting that selective microbial enrichment was promoted as Firmicutes (66%), Proteobacteria (13%), and Bacteroidetes (12%) (i.e., exoelectrogenic and butyrate producing phyla) which were dominant in the MXene-coated biochar biofilm. These results show that biochar modification is an effective technique for achieving selective products through MES.

Enhanced product selectivity in the microbial electrosynthesis of butyrate using a nickel ferrite-coated biocathode.

Microbial electrosynthesis (MES) is a potential sustainable biotechnology for the efficient conversion of carbon dioxide/bicarbonate into useful chemical commodities. To date, acetate has been the main MES product; selective electrosynthesis to produce other multi-carbon molecules, which have a higher commercial value, remains a major challenge. In this study, the conventional carbon felt (CF) was modified with inexpensive nickel ferrite (NiFe2O4@CF) to realize enhanced butyrate production owing to the advantages of improved electrical conductivity, charge transfer efficiency, and microbial-electrode interactions with the selective microbial enrichment. Experimental results show that the modified electrode yielded 1.2 times the butyrate production and 2.7 times the cathodic current production of the CF cathode; product selectivity was greatly improved (from 37% to 95%) in comparison with CF. Microbial community analyses suggest that selective microbial enrichment was promoted as Proteobacteria and Thermotogae (butyrate-producing phyla) were dominant in the NiFe2O4@CF biofilm (~78%). These results demonstrate that electrode modification with NiFe2O4 can help realize greater selective carboxylate production with improved MES performance. Hence, this technology is expected to be greatly useful in future reactor designs for scaled-up technologies.

MnCo2O4 coated carbon felt anode for enhanced microbial fuel cell performance.

A highly efficient anode is very crucial for an improved microbial fuel cell (MFC) performance. In this study, a binder-free manganese cobalt oxide (MnCo2O4@CF) anode was synthesized using a conventional carbon felt (CF) by a facile hydrothermal method. A large electrochemically active and rough electrode surface area of MnCo2O4@CF anode improved the substrate fluxes and microbial adhesion/growth. Furthermore, the electrochemical tests on the synthesized anode confirmed the superior bioelectrochemical activity, reduced ion transfer resistance, and excellent capacitance. This resulted in an improved power density (945 mW/m2), which was 3.8 times higher than that of CF anode. The variable valence state, high stability and biocompatibility of MnCo2O4@CF resulted in continuous current density performance for five MFC cycles. High-throughput biofilm analysis revealed the enrichment of electricity producing phylum of Proteobacteria and Bacteroidetes (∼90.0%), which signified that the modified MnCo2O4 anode accelerated the enrichment of electro-active microbes.

Nickel ferrite/MXene-coated carbon felt anodes for enhanced microbial fuel cell performance.

In recent years, the modification of electrode materials for enhancing the power generation of microbial fuel cells (MFCs) has attracted considerable attention. In this study, a conventional carbon felt (CF) electrode was modified by NiFe2O4 (NiFe2O4@CF), MXene (MXene@CF), and NiFe2O4-MXene (NiFe2O4-MXene@CF) using facile dip-and-dry and hydrothermal methods. In these modified CF electrodes, the electrochemical performance considerably improved, while the highest power density (1385 mW/m2), which was 5.6, 2.8, and 1.4 times higher than those of CF, NiFe2O4@CF, and MXene@CF anodes, respectively, was achieved using NiFe2O4-MXene@CF. Furthermore, electrochemical impedance spectroscopy and cyclic voltammetry results confirmed the superior bioelectrochemical activity of a NiFe2O4-MXene@CF anode in a MFC. The improved performance could be attributed to the low charge transfer resistance, high conductivity and number of catalytically active sites of the NiFe2O4-MXene@CF anode. Microbial community analysis demonstrated the relative abundance of electroactive bacteria on a NiFe2O4-MXene@CF anodic biofilm rather than CF, MXene@CF, and NiFe2O4@CF anodes. Therefore, these results suggest that combining the favorable properties of composite materials such as NiFe2O4-MXene@CF anodes can open up new directions for fabricating novel electrodes for renewable energy-related applications.

Reduced graphene oxide-TiO2/sodium alginate 3-dimensional structure aerogel for enhanced photocatalytic degradation of ibuprofen and sulfamethoxazole.

In this study, graphene oxide and titanium dioxide in combination with sodium alginate were used to synthesize the reduced graphene oxide-TiO2/sodium alginate (RGOT/SA) aerogel. The potential of RGOT/SA aerogel was evaluated for the photocatalytic degradation of ibuprofen and sulfamethoxazole and was compared with that of bare titanium dioxide nanoparticles. More than 99% removal of both the contaminants was obtained within 45-90 min by using the RGOT/SA aerogel under UV-A light. Mineralization of both the pollutants was also higher in case of RGOT/SA aerogel as compared to bare TiO2 nanoparticles. The optimal mass ratio of TiO2 nanoparticles with respect to graphene oxide was 2:1 in RGOT/SA aerogel in the presence of 1 wt% sodium alginate solution. High photodegradation of Ibuprofen was observed at neutral pH and acidic to neutral pH was found suitable for the photodegradation of sulfamethoxazole. Three-dimensional interconnected macroporous assembly, large surface area for settling TiO2 nanoparticles, efficient charge partitioning, and enhanced physical and chemical adsorption of ibuprofen and sulfamethoxazole on the surface of RGOT/SA aerogel were the significant characteristics of RGOT/SA aerogels. Moreover, ease of separation and recyclability of the RGOT/SA aerogel could further save the extra energy used to separate nanoparticles from the effluent.

Magnetic Ti3C2Tx (Mxene) for diclofenac degradation via the ultraviolet/chlorine advanced oxidation process.

In this study, a magnetic titanium carbide (Ti3C2Tx) MXene was synthesized through a one-step chemical co-precipitation method using ammonium bifluoride as a mild etchant and was investigated for photocatalytic degradation of diclofenac (DCF) via the ultraviolet (UV)/chlorine process. The DCF degradation was enhanced by the generation of active radicals such as the hydroxyl radical and reactive chlorine species compared with that resulting from UV and chlorination treatment alone as well as UV/H2O2 processes at pH 7. The first-order rate constant of the UV/chlorine process was 0.1025 min-1, which is 12.7 and 6.8 times higher than those of the only UV and UV/H2O2 processes, respectively. Magnetic nanoparticles on the surfaces of Ti3C2Tx sheets not only enhanced the adsorption capacity of the synthesized composite but also increased the rate of electron transfer in solution. In addition, the effects of different operating conditions such as magnetic Ti3C2Tx dose, pH, and initial chlorine concentration on DCF degradation were investigated. Magnetic Ti3C2Tx showed high stability and photodegradation efficiency during seven consecutive degradation reaction cycles. The derivatives of DCF during the photocatalytic degradation process were also investigated based on the observed intermediate products and a degradation pathway was proposed. Thus the synthesized magnetic Ti3C2Tx is a simple and affordable photocatalyst, which can significantly enhance DCF degradation in the UV/chlorine advanced oxidation process.

Unique selectivity and rapid uptake of molybdenum-disulfide-functionalized MXene nanocomposite for mercury adsorption.

A heterogeneous nanoadsorbent composed of two-dimensional Ti3C2Tx MXene nanosheets (MX) functionalized with nanolayered molybdenum disulfide (MoS2/MX-II) was synthesized by a facile hydrothermal treatment method and used to remove toxic mercuric ions (Hg2+). Mercury was adsorbed by the synergistic action of the sulfur (disulfide) and the oxygenated terminal groups of Ti3C2Tx in the MoS2-MX-II composite. Ultrasonication increased the surface area and interlayer distance of the Ti3C2Tx nanosheets, which enhanced the removal capability of the composite. As a result, 50 µmol/L of Hg2+ was reduced to 0.01 µmol/L in just 120 s, which is unprecedented kinetic behavior for mercury adsorption. Furthermore, the Langmuir adsorption isotherm fitted well with the adsorption data and revealed a maximum adsorption capacity of 7.16 mmol/g. To provide a practical demonstration of MoS2/MX-II, it was applied to mercury-contaminated wastewater, whose results showed that MoS2/MX-II was capable of removing Hg2+ at the ppb level with a distribution coefficient of 7.87 × 105 mL/g in the co-presence of various metal ions. Hydrothermal stability tests and SEM analysis confirmed the stability of MoS2-MX-II after it adsorbed a high concentration of Hg2+. Furthermore, MoS2-MX-II exhibited excellent recyclability as 0.08 mM of Hg2+ was completely removed even after five cycles. The results suggest the practical applicability of this type of heterogeneous nanocomposite for water purification.

Investigating the role of anodic potential in the biodegradation of carbamazepine in bioelectrochemical systems.

Anode potential is a critical factor in the biodegradation of organics in bioelectrochemical systems (BESs), but research on these systems with complex recalcitrant co-substrates at set anode potentials is scarce. In this study, carbamazepine (CBZ) biodegradation in a BES was examined over a wide range of set anode potentials (-200 to +600 mV vs Ag/AgCl). Current generation and current densities were improved with the increase in positive anode potentials. However, at a negative potential (-200 mV), current generation was higher as compared to that for +000 and +200 mV. The highest CBZ degradation (84%) and TOC removal efficiency (70%) were achieved at +400 mV. At +600 mV, a decrease in CBZ degradation was observed, which can be attributed to a low number of active bacteria and a poor ability to adapt to high voltage. This study signified that BESs operated at optimum anode potentials could be used for enhancing the biodegradation of complex and recalcitrant contaminants in the environment.

Exfoliation of Titanium Aluminum Carbide (211 MAX Phase) to Form Nanofibers and Two-Dimensional Nanosheets and Their Application in Aqueous-Phase Cadmium Sequestration.

A green approach was adopted to exfoliate a Ti2AlC MAX phase. The exfoliated nanostructures (Alk-Ti2Cfibr and Alk-Ti2Csheet) with exceptional mechanical, thermal, and water stabilites, as well as abundant oxygenated active binding sites, were synthesized via a controlled hydrothermal treatment in an alkaline environment. The successful synthesis of nanofibers and sheetlike nanostructures was inferred with scanning electron microscopy and X-ray diffraction analyses. Field emission scanning electron microscopy, field-emission transmission electron microscopy, Raman spectroscopy, Brunauer-Emmett-Teller surface area, ζ-potential analyses, and X-ray photoelectron spectroscopy were utilized to investigate the material's characteristics and its structural changes after metal ion adsorption. Heavy metal ion adsorption of the synthesized nanostructures was assessed in batch tests based on Cd2+ ion sequestration; the maximum adsorption capacity for Cd2+ was 325.89 mg/g, which is among the highest values reported for similar materials such as graphene oxide and its derivatives. The detailed quantitative investigation confirmed the interaction of hydroxyl groups with Cd2+ ions by electrostatic interactions, adsorption-coupled oxidation, and complex formation. Owing to their unique structure, high porosity, large specific surface area, and oxygenated functional groups, Alk-Ti2Csheet nanosheets were highly time-efficient for Cd2+ removal. Moreover, Alk-Ti2Cfibr and Alk-Ti2Csheet nanostructures were tested for simulated groundwater, showing that synthesized nanostructures were capable for removing Cd2+ ions at the ppb level. The results obtained from this study suggested that nanostructures synthesized using this route could provide a new approach to prepare and exfoliate additional MAX phases for the removal of heavy metal ions and other pollutants in the environment.

Effective phosphorus removal using chitosan/Ca-organically modified montmorillonite beads in batch and fixed-bed column studies.

In this study, phosphorus removal from aqueous solution was investigated using chitosan/Ca-organically modified montmorillonite (chitosan/Ca-OMMT) beads in batch and fixed-bed column systems. The XPS spectra confirmed that the calcium ions on the surface of the beads play a dominant role in capturing phosphate ions through surface complexation. The batch adsorption experimental data were fitted with pseudo-second-order kinetics and the Langmuir isotherm. The maximum adsorption capacity of the chitosan/Ca-OMMT beads was found to be 76.15 mg/g at an initial phosphate concentration of 100 mg/L at 25 °C. High phosphate uptake is achieved over the wide pH range 3-11, as well as in the presence of competing anions such as Cl-, NO3-, SO42-, and HCO3-. Furthermore, the chitosan/Ca-OMMT beads can be easily regenerated using 0.1 mol/L NaOH as a desorption agent with more than 83.97% adsorption capacity remaining after five adsorption/desorption cycles. The Thomas, Yoon-Nelson, and Adams-Bohart models were applied to the experimental data to predict the breakthrough curves using non-linear regression; the Yoon-Nelson model showing the best agreement with the breakthrough curves. These findings demonstrate that chitosan/Ca-OMMT beads can be used as a cost-effective and environment-friendly adsorbent for the removal of phosphate from wastewater.