Adsorption Of Pesticides Research Articles

Facile adsorption of organophosphate pesticides over HKUST-1 MOFs.

The recovery of organophosphate pesticides (OPPs) from aqueous solutions is imperative considering their agricultural and environmental implications. Among various mitigation approaches used for OPPs' removal, adsorption offers many advantageous features for OPPs abatement owing to its benign nature, cost-effective processing, and non-requirement of excessive equipment. This research describes the adsorptive removal of three organophosphate pesticides (OPPs) namely chlorpyrifos (CPF), methyl parathion (MP), and malathion (MAL) by HKUST-1 (HKUST = Hong Kong University of Science and Technology) metal-organic framework (MOF). The synthesis of HKUST-1 MOFs was confirmed by various spectroscopic and microscopic techniques. The adsorption kinetics was systematically investigated by varying three parameters to include solution pH, contact time, and initial pesticide concentration. Among all the three pesticides, HKUST-1 showed enhanced removal of CPF in terms of pH, resulting in an adsorption capacity of 1.82mg·g-1. However, under the effect of contact time at 60min, the adsorption capacity of HKUST-1 for PM, MAL, and CPF were computed to be 1.83, 1.79, and 0.44mg·g-1, respectively. Besides, HKUST-1 showed a remarkable performance towards adsorptive removal of MAL (14.01mg·g-1 at 10mg·L-1 concentration) with linear increase in adsorption capacity as the function of initial pesticide concentration. The MOFs were also able to retain ca. 50% of their adsorption efficiency over the course of five cycles of adsorptive removal of CP. In the future, a comprehensive data table showing the performance of various MOFs against various OPPs can be constructed on the basis of parameters used in this study.

Remediation of pesticides contaminated water using biowastes-derived carbon rich biochar

The competition impact and feedstock type on the removal of water pesticides using biochar have not yet been sufficiently investigated. Therefore, here we investigated the potentiality of three different biochars (BCs) derived from rice husk (RHB), date pit (DPB), and sugarcane bagasse (SBB) biowastes for the simultaneous removal of ten pesticides from water in a competitive adsorption system. The BCs structural characterization and morphology were investigated by XRD, FTIR spectroscopy and SEM analysis. The potential adsorption mechanisms have been investigated using various isothermal and kinetic models. RHB showed the highest removal percentages (61% for atrazine/dimethoate and 97.6% for diuron/chlorfenvinphos) followed by DPB (56% for atrazine/dimethoate and 95.4% for diuron/chlorpyrifos) and then SBB (60.8% for atrazine/dimethoate and 90.8% for chlorpyrifos/malathion). The higher adsorption capacity of RHB and DPB than SBB can be due to their high total pore volume and specific surface area (SSA). Langmuir model described well the sorption data (R2 = 0.99). Adsorption equilibrium was achieved after 60 min for RHB, and 120 min for both DPB and SBB. The optimum adsorbent dose (g/L) was 10 for RHB and 4 for DPB and SBB. The removal efficiency of pesticides was enhanced by decreasing pH from 9 to 5 by RHB and to 3 by DPB and SBB. XRD and FTIR spectroscopy confirmed that BCs contain some active adsorption groups and metal oxides such as MgO, SiO, Al2O3, CaO, and TiO2 that can play an effective role in the pesticides sorption. BET-N2 adsorption analysis demonstrated that the BC pore size contributes significantly to pesticide adsorption. These findings indicate that RHB, DPB, and SBB have ability for adsorption of water pesticides even under acidic conditions. Therefore, the rice husk, date pit, and sugarcane bagasse biowastes could be pyrolyzed and reused as effective and low-cost sorbents for elimination of hazardous substances such as pesticides in the aqueous environments.

Effectiveness of biochar as an adsorbent for pesticides: Systematic review and meta-analysis

The use of pesticides is intense in agriculture and has caused contamination in water, air and soil. This fact led to the need to study strategies that can minimize the effects that these pesticides have caused to the environment. In this context, biochar appears, as a type of material that has the ability to remove chemical substances, and because they can be activated with different chemical agents, they are extremely effective in the adsorption of toxic substances. Therefore, the aim of the study was to evaluate the use of biochar as a bioadsorbent for pesticides. This is a systematic review with meta-analysis and meta-regression, as the PRISMA protocol recommendations. Studies from the last 20 years were included, with at least the abstract available and considering preferentially experimental studies. Qualitative studies or studies with high risk of bias, other reviews and duplicates were excluded. The variables analyzed were the presence of factors that prove the effectiveness or not of pesticide adsorption. Studies with a superficial approach or those that do not show positivity or negativity in relation to the outcome were excluded. The search was conducted on the sources: Scopus, Web of Science electronic databases, PubMed (of the US National Library of Medicine, National Institutes of Health) and ScienceDirect (Elsevier). For better investigative determination, the data were searched separately. The descriptors used for the search were the following: Agrochemicals AND Activated Carbon AND Adsorption. Initially, 2431 references were found, from which 14 were selected to compose the meta-analysis review. With the joint analysis of the data, it was possible to verify using the random model (since the studies assess different contexts) that there is a proportion of effectiveness of the intervention of 81% (with a 95% confidence interval), ranging from 75 to 88%, which is represented by the meta-analysis diamond that is the final result of the statistical analysis. Biochar is effective in removing impurities, even including features such as low cost. There is a considerable lack of studies on the topic of pesticide adsorption with the use of biochar. The studies approach a very heterogeneous perspective on the subject, exposing different contexts.

Prediction of organophosphorus pesticide adsorption by biochar using ensemble learning algorithms.

Machine learning (ML) models have become a potent tool for advancing environmentally conscious research in materials science, allowing the prediction of wastewater treatment efficacy using eco-materials. In this study, we showcase the potential of an advanced decision tree-based ensemble learning algorithm to model the eviction of emerging organophosphate-based pesticidal pollutants in aqueous systems. The model is trained using laboratory-based biochar adsorption data, and it establishes the relationship between independent experimental factors and the % organophosphate pesticide adsorption efficiency as the output parameter. We classified the experimental dataset into input and output parameters to build the model. The input parameters included pyrolysis temperature, solution pH, surface area, pore volume, and initial pesticide concentration. Grid search optimization in Python was employed to train the model using sets of input-output patterns. The results indicated that the XGBoost-based ensemble ML framework provides the best forecast for pesticide adsorption on the biochar matrix, achieving high scores for the regularization coefficient (R2train = 0.998, R2test = 0.981). The concentration of the organophosphorus compound and the morphology of biochar significantly influenced the pesticide adsorption behavior. These findings demonstrate the potential of using ensemble learning algorithms for the balanced design of carbon-enriched biomaterials to remove emerging micropollutants from water effectively.

Adsorption and removal of the harmful pesticide 2,4-dichlorophenylacetic acid from an aqueous environment via coffee waste biochar: Synthesis, characterization, adsorption study and optimization via Box-Behnken design

This study looked at the effectiveness of a biochar made from coffee waste (CWB) in removing the harmful pesticide 2,4-dichlorophenylacetic (2,4-D) from water. The trials' conclusive findings showed that CWB is an effective adsorbent for removing 2,4-D from aqueous solutions. A variety of methods, including Scanning electron microscope (SEM), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET) analysis, were used to study the CWB. The surface area and pore volume of CWB are comparatively large (422.4 m2/g), and (0.46 cm3/g), respectively. Interestingly, our results show that adsorption behaviour is significantly impacted by changes in solution pH. At pH 6, dosage 0.02 g, the best conditions for high adsorption capacity were discovered. Since adsorption is an endothermic process, its capacity increases as temperature does. The adsorption process was fitted to Langmuir Isothermally and pseudo-second-order model kinetically. It was discovered that a chemisorption mechanism was at work during the entire process. Box-Behnken design (BBD) with Response Surface Methodology (RSM) was used to optimize the parameters such as solution pH, absorbent dosage, temperature and time. Following the instructions, we were able to extract the values of (ΔH°), (ΔS°), and (ΔG°) for 2,4-D, which shown that when utilizing CWB as an adsorbent, the reaction was endothermic and spontaneous. The synthesized CWB adsorbent exhibits outstanding reusability and can be used in adsorption-desorption operations up to five times. It was proposed that the interaction between CWB and 2,4-D may take place through a variety of mechanisms after additional research was conducted to better understand the relationship, including pore filling, π-π interaction, H-bonding, or electrostatic interaction. Our research is the first to demonstrate the efficacy of using CWB as an adsorbent to remove 2,4-D from wastewater samples. The conclusions show that a pH value of 6 is necessary to produce 2,4-D's greatest adsorption capacity onto CWB, which is 276.3 mg/g.

Soil metabolomics: A powerful tool for predicting and specifying pesticide sorption

Sorption regulates the dispersion of pesticides from cropped areas to surrounding water bodies as well as their persistence. Assessing the risk of water contamination and evaluating the efficiency of mitigation measures, requires fine-resolution sorption data and a good knowledge of its drivers. This study aimed to assess the potential of a new approach combining chemometric and soil metabolomics to estimate the adsorption and desorption coefficients of a range of pesticides. It also aims to identify and characterise key components of soil organic matter (SOM) driving the sorption of these pesticides. We constituted a dataset of 43 soils from Tunisia, France and Guadeloupe (West Indies), covering extensive ranges of texture, organic carbon and pH. We performed untargeted soil metabolomics by liquid chromatography coupled with high-resolution mass spectrometry (UPLC-HRMS). We measured the adsorption and desorption coefficients of three pesticides namely glyphosate, 2,4-D and difenoconazole for these soils. We developed Partial Least Square Regression (PLSR) models for the prediction of the sorption coefficients from the RT-m/z matrix and conducted further ANOVA analyses to identify, annotate and characterise the most significant constituents of SOM in the PLSR models. The curated metabolomics matrix yielded 1213 metabolic markers. The prediction performance of the PLSR models was generally high for the adsorption coefficients Kdads (0.3 < R2 < 0.8) and for the desorption coefficients Kfdes (0.6 < R2 < 0.8) but low for ndes (0.03 < R2 < 0.3). The most significant features in the predictive models were annotated with a confidence level of 2 or 3. The molecular descriptors of these putative compounds suggest that the pool of SOM compounds driving glyphosate sorption is reduced compared to 2,4-D and difenoconazole, and these compounds are generally more polar. This approach can provide estimates of the adsorption and desorption coefficients of pesticides, including polar pesticide, for contrasted pedoclimates.

Green Synthesis of Nanoparticles Mediated by Deep Eutectic Solvents and Their Applications in Water Treatment

The use of environmentally friendly deep eutectic solvents (DES) in green synthesis of different types of nanoparticles has garnered increasing interest in recent years. The application of these materials in water treatment, mainly by adsorption or degradation, is emerging as a sustainable alternative to conventional methodologies. However, the information about the green synthesis of nanoparticles (NPs) using DES is dispersed in the literature. This review is focused on compiling and systematizing information regarding DES-mediated NP synthesis, the application of these NPs in water treatment, and future perspectives of these technologies. DES represent an excellent alternative to traditional solvents in NP synthesis due to their low toxicity, low cost, and being environmentally friendly. The possible NP surface functionalization with DES is also attractive as it plays a pivotal role in processes related to water treatment. Modification and synthesis of carbon nanotubes, graphene oxides, magnetic iron oxides, among others, for the adsorption and degradation of organic dyes, pharmaceuticals, metal ions, herbicides, pesticides, and other water contaminants found in recent literature are presented in this work. Finally, the possibility to control NP size and shape can be helpful in the design of new materials for a specific application.

Adsorption of pesticides using graphene oxide through computational and experimental approach

Pesticides are classified as rodenticides, insecticides, fungicides, and herbicides since they have the potential to kill a variety of pests, such as rodents, insects, fungus, weeds, etc. Due to their specific usage in the agricultural sector to ensure crop output and productivity, pesticide contamination is now one of the most serious threats to general public health across the world. Therefore, the authors thought of finding approaches to remove the pesticides (metribuzin and fipronil) through adsorption with the experimental techniques {scanning electron microscopic (SEM) technique, UV–Visible spectroscopy, powder x-ray diffraction (XRD)} and computational calculations using Gaussian (DFT calculations) and molecular dynamics (MD) simulations. It can be easily understood about the feasibility of the formation of the conjugates (GO-MET and GO-FIP) through adsorption. Therefore, GO could be used as promisng candidate for the removal of metribuzin (MET) and fipronil (FIP).

Efficient removal of imidacloprid pesticide by two eco-friendly activated carbons

In this study, the removal of imidacloprid (IMD) pesticide onto activated carbon produced from nut shells of hazelnut (HAC), and walnut (WAC) has been investigated. The prepared activated carbons were characterised by total carbon, nitrogen and hydrogen content, surface areas and pore volume. Fourier-transform infrared (FTIR), and scanning electron microscopy (SEM) were studied before and after adsorption experiments. Effects of adsorbent dose (0.02–0.2 g), contact time (10–120 min), initial imidacloprid concentration (10–100 mg∙dm –3), and pH (1–8), and temperatures (25–50°C) on the removal of IMD pesticide by HAC and WAC in the batch mode were studied. The removal percentage of imidacloprid pesticide by HAC and WAC was 93.79% and 94.72%, respectively. The study showed that the pseudo-second-order kinetics model fitted well for both activated carbons. Moreover, adsorption isotherm results were evaluated using Freundlich, Langmuir and Temkin isotherm models. The adsorption results correlated well with the Langmuir isotherm model ( R2 = 0.987 and 0.964) with maximum adsorption capacities of 76.923 and 83.333 mg∙g –1 for HAC and WAC, respectively, and an equilibrium time within 120 min. The nature of the adsorption of imidacloprid pesticide onto HAC and WAC is exothermic, spontaneous and physical in nature. The two prepared activated carbons (HAC, WAC) were successfully regenerated for three cycles and could be used as an effective and low-cost adsorbent for the removal of IMD pesticide from aqueous solutions. The production of the activated carbons of HAC and WAC will provide minimisation of these wastes in the environment.

Application of Viscose-Based Porous Carbon Fibers in Food Processing-Malathion and Chlorpyrifos Removal.

The increasing usage of pesticides to boost food production inevitably leads to their presence in food samples, requiring the development of efficient methods for their removal. Here, we show that carefully tuned viscose-derived activated carbon fibers can be used for malathion and chlorpyrifos removal from liquid samples, even in complex matrices such as lemon juice and mint ethanol extract. Adsorbents were produced using the Design of Experiments protocol for varying activation conditions (carbonization at 850 °C; activation temperature between 670 and 870 °C; activation time from 30 to 180 min; and CO2 flow rate from 10 to 80 L h-1) and characterized in terms of physical and chemical properties (SEM, EDX, BET, FTIR). Pesticide adsorption kinetics and thermodynamics were then addressed. It was shown that some of the developed adsorbents are also capable of the selective removal of chlorpyrifos in the presence of malathion. The selected materials were not affected by complex matrices of real samples. Moreover, the adsorbent can be regenerated at least five times without pronounced performance losses. We suggest that the adsorptive removal of food contaminants can effectively improve food safety and quality, unlike other methods currently in use, which negatively affect the nutritional value of food products. Finally, data-based models trained on well-characterized materials libraries can direct the synthesis of novel adsorbents for the desired application in food processing.

Investigation of the physicochemical properties of amine-modified organoclays influenced by system pH and their potential to adsorb anionic herbicide

Organically modified montmorillonites have already attracted the attention of researchers due to their eco-friendly characteristics and versatile application in our daily lives. Their application is now being widely explored as a potential carrier for preparing solid-laden controlled release formulations (CRFs) of herbicides. The suitability of a new formulation mainly depends on herbicide releasing behaviour under various conditions, which is governed by the interaction mechanisms between carrier materials and target herbicide. The physicochemical properties of carriers and herbicides are the key components for establishing the probable interaction mechanisms between them. The physicochemical properties of amine-modified organoclays are mostly pH dependent and this experiment investigated the effect of pH on surface chemistry and how it changes when system pH is varied. Results revealed that the organoclays converted from protonated to deprotonated conditions as well as from hydrophobic to hydrophilic states with increasing system pH, from acidic to alkaline conditions. The release of surfactants from the organoclays was higher in acidic and alkaline pH conditions than in neutral pH. The release of major structural elements was highest in acidic conditions, but gradually abated with increasing system pH until neutral conditions were achieved. After that they increased slightly to an alkaline state, except for iron (Fe). Zeta values of both organoclays gradually diminished as system pH increased. The surface area of organoclays was highest at neutral pH, and gradually waned towards acidic and alkaline pH. This ultimately affects adsorption of anionic herbicide onto the various pH-adjusted organoclays. The adsorption was highest at around the pKa value of the herbicide and gradually declined with increasing system pH to a neutral state, and then slightly increased towards a higher pH. Based on this, it can be concluded that system pH exerts a significant influence on the physicochemical properties of amine-modified organoclays. This may affect firstly, adsorption of pesticides onto the interlayer gallery of the organoclays for CRFs of pesticides; and secondly, the formulation’s releasing behaviour and ultimate efficacy of the synthesised formulation.

Synthesis of thermoresponsive PNIPAm nanogel adsorbent by microwave-assisted polymerization for wastewater treatment application

This research demonstrated the fast synthesis technique using microwave-assisted polymerization for the preparation of thermoresponsive poly(N-isopropylacrylamide) (PNIPAm) nanogel which was to be used for paraquat pesticide adsorption. PNIPAm nanogel was synthesized by free-radical polymerization in an aqueous solution using water-soluble ammonium peroxodisulfate (APS) and N,Ń-methylenebisacrylamide (BIS) as initiators and cross-linker, respectively. Microwave irradiation was used as an alternative heating technique and its efficiency was compared to that of the conventional heating method. The results showed that reaction time could be greatly shortened from several hours to only 20 min with the yield of PNIPAm nanogel of approximately 65 % using microwave heating method. The FTIR analysis confirmed that microwave irradiation did not alter the chemical structure of PNIPAm nanogel. The cross-linker concentrations and the sequence of cross-linker addition affected the hydrodynamic diameter of PNIPAm nanogel. The hydrodynamic diameter of swollen PNIPAm nanogels at 25 °C decreased as increasing the cross-linker concentrations and then further decreased when the cross-linker was added after 10 min of the irradiation time. Besides, all PNIPAm nanogel showed well thermoresponsive reversibility over 5 cycles, across the volume phase transition temperature (VPTT) at around 32 °C. The adsorption and release mechanisms of the paraquat took advantage of the phase transition change (swelling-collapse) in response to temperature stimuli, respectively. The PNIPAm nanogel synthesized from the microwave heating method had a profound effect on paraquat adsorption, having 60 – 70 % adsorption with a paraquat release of around 35 – 45 %. These results demonstrated that PNIPAm nanogels could be used as an alternative adsorbent material for industrial wastewater treatment.

Adsorption and effective removal of organophosphorus pesticides from aqueous solution via novel metal-organic framework: Adsorption isotherms, kinetics, and optimization via Box-Behnken design

The purpose of this study was to examine the efficiency of a tin-metal organic framework (Sn-MOF) to remove the organophosphate pesticide diazinon (DZ) from water. The results of the experiments conducted were compelling and demonstrated that Sn-MOF is a powerful adsorbent for removing DZ from aqueous solutions. The Sn-MOF was analyzed using various techniques including SEM, XRD, and BET analysis. It showed that the surface area of Sn-MOF is considerable high 897.69.75 m2/g and a significant pore volume of 1.04 cm3/g. Surface characterization was performed to determine the point of zero charge. To investigate the impact of pH levels on adsorption equilibrium, we carried out batch tests. Interestingly, our findings indicate that variations in solution pH have a significant impact on adsorption behavior. The optimum condition to have high adsorption capacity was found at pH 6, dose 0.01 g, and the temperature, as the temperature rises, the adsorption capacity rises because the process of adsorption is endothermic. The efficacy of DZ adsorption on Sn-MOF was extensively evaluated using kinetic models, specifically adhering to the pseudo-second-order model. Additionally, the Langmuir isotherm model was applied to accurately fit the adsorption process. It was observed that the overall process involved a chemisorption mechanism. In order to optimize the parameters such as absorbent dosage, solution pH, temperature, and time, Box-Behnken design (BBD) with Response Surface Methodology (RSM) was employed. Following the instructions, we were able to extract the values of (ΔH°), (ΔS°), and (ΔG°) for DZ, which indicated that the process was endothermic and spontaneous when using Sn-MOF as an adsorbent. The Sn-MOF adsorbent that was synthesized shows remarkable reusability and can be cycled up to five times for adsorption-desorption processes. The newly developed adsorbent's efficiency was evaluated as a proof of concept for purifying wastewater samples on a small scale in a laboratory. Additional study was done to better understand the way that Sn-MOF and DZ interact, and it was suggested that the interaction may occur through various mechanisms, including π-π interaction, pore filling, H-bonding, or electrostatic interaction. The use of Sn-MOF as an adsorbent presents a simple and effective approach for the treatment of industrial wastewater and water filtration. The effectiveness of utilizing Sn-MOF as an adsorbent to remove DZ from wastewater samples has never been demonstrated before, but our study is the first to do so. According to the results, a pH value of 6 is required to achieve the highest adsorption capability of DZ onto Sn-MOF, with a value of 587.39 mg.g−1.

Cysteine-functionalization zirconium-organic framework for efficient adsorption 2,4-dichlorophenylacetic acid from water

2,4-Dichlorophenoxyacetic acid (2,4-D) is one of the most widely used pesticides in the world, which pose hazardous effects to the aquatic environment and human health due to its long-term and extensive use. In this work, MOF-808-Cys with highly water stable was prepared by one-pot method using L-cysteine modified Zr-based organic framework. Cysteine confers a variety of functional groups to MOF-808, enabling its chemical binding to the target substrate 2,4-dichlorophenylacetic acid (2,4-D). Adsorption experiments reveal that MOF-808-Cys has a higher adsorption efficiency (90%) toward 2,4-D than pristine MOF-808 (75%). Moreover, the adsorption kinetics confirms that the adsorption behavior follows a pseudo-second-order model with intraparticle diffusion. Experimental and characterization analysis show that physical adsorption and chemisorption synergistic improved adsorption capacity and adsorption efficiency. The -NH2 and -SH moiety are introduced into MOF-808 to enhance the adsorption performance by chemical adsorption. This study provides an effectively strategy of functional group modification to enhance the adsorption of pesticides and antibiotic pollutants in wastewater.

Effectiveness application of Chitosan/Alginic/Copper–organic framework beads on removal of carbaryl carbamate from wastewater

In this study, we concentrated on creating copper-benzene dicarboxylate metal organic frameworks (Cu-BDC MOFs) utilizing scrap copper metal that was obtained from used copper electrical wires. For practical applications, powdered forms of MOFs are typically poorly processed; as a result, Cu-BDC/chitosan/alginic beads were created by cross-linking chitosan, alginic acid, and Cu-BDC MOF. The carbaryl pesticide adsorption from wastewater still challenge due to its low adsorption capacity. Therefore, Copper-BDC/chitosan/alginic beads were compared to chitosan/alginic beads, and the results showed that the latter had a more effective adsorption capacity (225.51 mg g−1) than the former (95.71 mg g−1). Through the use of X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX), and Brunauer-Emmett-Teller (BET), the physical and chemical properties of chitosan/alginic and Cu-BDC/chitosan/alginic beads were examined. It's interesting to note that the Cu-BDC/chitosan/alginic beads' morphology is homogeneous and has sizable holes. The uniqueness of the produced materials lends itself to desirable characteristics for the targeted isolation of carbaryl from wastewater. As a result of the current work, MOFs materials for the selective removal of pesticides from wastewater will commercially available and easily process.

Highly defective copper-based metal-organic frameworks for the efficient adsorption and detection of organophosphorus pesticides: An experimental and computational investigation

Organophosphorus pesticide (OP) residues pose a serious threat to human health, motivating the search for novel adsorbents and detection methods. Herein, defective copper-based metal organic frameworks (Cu-MOFs) were synthesized by the reaction of Cu2+ ions and 1,3,5-benzenetricarboxylate linkers in the presence of acetic acid. As the amount of acetic acid increased, the crystallization kinetics and morphology of the Cu-MOFs changed, leading to mesoporous Cu-MOFs with many large surface pores (defects). Adsorption studies of OPs revealed the defective Cu-MOFs showed faster pesticide adsorption kinetics and higher pesticide adsorption capacities. Density functional theory calculations showed that pesticide adsorption in the Cu-MOFs was mainly electrostatic. A dispersive solid phase extraction method was developed based on a defective Cu-MOF-6 for rapidly extracting pesticides from food samples. The method allowed pesticide detection over a wide linear concentration range, low limits of detection (0.0067–0.0164 µg L−1) and good recoveries in pesticide-spiked samples (81.03–109.55%).

Fabrication of amorphous metal-organic framework in deep eutectic solvent for boosted organophosphorus pesticide adsorption

Herein, we describe a new and sustainable strategy of directly constructing the amorphous metal-organic framework (MOF) through the use of deep eutectic solvent (DES) for the highly effective and efficient adsorption of organophosphorus pesticide from contaminated water. The as-obtained products possessed nanosize morphology (as small as 40 nm), hierarchical pores ranging from 1.16 to 12.3 nm, high porosity up to 0.5954 cm3 g−1, and abundant unsaturated metal centers. The presence of structural disorder increased the number of active sites and promoted the diffusion of target molecules, leading to enhance host-guest interactions. These properties were beneficial for the application of the material in the enrichment adsorption of profenofos. The amorphous UiO-66 with the highest content of defect disorder (4.408) displayed a remarkably high affinity toward profenofos, resulting in an exceptional adsorbate uptake capacity over 1300 mg·g−1. This is a three-fold enhancement compared to its crystalline counterpart. And its performance surpassed that of most previously reported absorbents. Additionally, the adsorption behavior and mechanism of amorphous UiO-66 toward profenofos were elucidated by high-revolution X-ray photoelectron spectroscopy (XPS) and various models. The results revealed a multi-layer heterogeneous adsorption, involving multiple sorption process. The profenofos adsorption mechanisms over amorphous UiO-66 mainly rely on hydrogen bonding, Zr-O-P bonds, and P-Zr bonds. Moreover, the amorphous UiO-66 exhibited outstanding regeneration and reusability characteristics, making it a stable and promising adsorbent for water remediation. Its efficient and rapid removal of pollutants holds great potential for practical applications, while also providing guidelines for the design and optimization of next-generation sorbent.

Enhanced ultrasonic adsorption of pesticides onto the optimized surface area of activated carbon and biochar: adsorption isotherm, kinetics, and thermodynamics

Enhanced ultrasonic adsorption of pesticides onto the optimized surface area of activated carbon and biochar: adsorption isotherm, kinetics, and thermodynamics

Application of Hydrogen-Bonded Organic Frameworks in Environmental Remediation: Recent Advances and Future Trends

The hydrogen-bonded organic frameworks (HOFs) are a class of porous materials with crystalline frame structures, which are self-assembled from organic structures by hydrogen bonding in non-covalent bonds π-π packing and van der Waals force interaction. HOFs are widely used in environmental remediation due to their high specific surface area, ordered pore structure, pore modifiability, and post-synthesis adjustability of various physical and chemical forms. This work summarizes some rules for constructing stable HOFs and the synthesis of HOF-based materials (synthesis of HOFs, metallized HOFs, and HOF-derived materials). In addition, the applications of HOF-based materials in the field of environmental remediation are introduced, including adsorption and separation (NH3, CO2/CH4 and CO2/N2, C2H2/C2He and CeH6, C2H2/CO2, Xe/Kr, etc.), heavy metal and radioactive metal adsorption, organic dye and pesticide adsorption, energy conversion (producing H2 and CO2 reduced to CO), organic dye degradation and pollutant sensing (metal ion, aniline, antibiotic, explosive steam, etc.). Finally, the current challenges and further studies of HOFs (such as functional modification, molecular simulation, application extension as remediation of contaminated soil, and cost assessment) are discussed. It is hoped that this work will help develop widespread applications for HOFs in removing a variety of pollutants from the environment.

The synthesis, application and mechanism of a novel Zr-based magnetic MOFs adsorption material

In the current study, a novel material Fe3O4@PDA@UiO-67 was synthesized by combining magnetic polydopamine (PDA) and zirconium-based metal-organic framework UiO-67 as well as applied as an adsorbent to remove azole fungicides in environmental water. The morphology and structure of this synthesized material were confirmed through a series of characterization. Modifying of UiO-67 on magnetic PDA could dramatically expand the surface area, enlarge the porosity and pore volume, and therefore improving the adsorption of pesticides. In addition, the effects of adsorbent dosage, solution pH, ionic strength and material composition on adsorption capability were evaluated and optimized. Under optimal conditions, the removal efficiencies were more than 90%. Furthermore, the adsorption mechanism was revealed by Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS) analysis and density functional theory calculations. Hydrogen bonds were considered as the major intermolecular interaction between the MOF backbones and the target pollutants. The binding energy ∆Ebof epoxiconazole and flusilazole are − 18.63 kJ/mol and − 28.54 kJ/mol, respectively, which are in consist with the maximum adsorption value for flusilazole (43.54 mg g−1) and flusilazole (54.60 mg g−1). In general, the synthesized Fe3O4@PDA@UiO-67 shows great potential in removing the environmental pollutants.