Adsorption Of Pesticides Research Articles

Facile Removal of Pesticides from Aqueous Solutions Using Magnetic Nanocomposites. II. Adsorption experiments and kinetic study

Using previously presented magnetic inorganic/organic magnetic nanocomposites, the adsorption of two known commercial-available pesticides (active ingredients deltamethrin and thiamethoxam, respectively) was achieved. The differences in adsorption observed can be explained by the reduced affinity of the nitro group in the ionized form from thiamethoxam towards the carboxyl groups from chitosan. From the kinetics studies it was determined that in case of thiamethoxam adsorption process is exothermic in nature, while in the case of deltamethrin the process is endothermic. The Sips isotherm was more suitable to describe the adsorption of pesticides on prepared adsorbents. The maximum adsorption capacity determined for the developed material was 247.12 mg/g (for deltamethrin) and 53.29 mg/g (for thiamethoxam).

Modelling the Effect of Sorbate-Sorbent Interphase on the Adsorption of Pesticides and Herbicides by Historical Data Design

Statistical modelling was employed to analyze the effect of sorbate-sorbent interphase on the adsorption of pesticides and herbicides from aqueous media. The dataset used for this study was sourced from relevant and reputable published papers in the past five years. Sixty-six lines of data were analyzed using response surface methodology (RSM) and historical data design (HDD) on Design expert. Five parameters were considered in the study: adsorbate’s relative molecular mass (RMM), adsorbent specific surface area (SBET), adsorbent effective surface area eSBET (i.e., the portion of the SBET occupied by the sorbate molecules), the water solubility of adsorbate, and adsorbate preferential adsorption (i.e., the ratio of the amount of sorbate on the sorbent to the amount in solution). From the analysis of variance, it was observed that the SBET of the adsorbent was the most significant determining for the adsorption capacity, q (at a significance level of p <0.05). Other significant factors were the RMM, eSBET, and the preferential adsorption. Generally, solubility did not show any significant influence on the q. The response surface model had an R2 value of 0.9945 and an adjusted R2 value of 0.9927. Conclusively, the q of an adsorbent towards an herbicide or a pesticide increases with increasing eSBET and SBET, irrespective of the sorbate’s solubility and molecular mass.

A trifluoromethyl-grafted ultra-stable fluorescent covalent organic framework for adsorption and detection of pesticides

A fluorine-rich ultra-stable fluorescent covalent organic framework for adsorption and detection of pesticides was designed and prepared via the Povarov reaction in a flask.

DFT study of adsorption of glyphosate pesticide on Pt-Cu decorated pyridine-like nitrogen-doped graphene

Density functional theory (DFT) studies have been performed on the unprecedented adsorption of glyphosate pesticide on modified pyridine-like nitrogen-doped graphene (PNG) for the purpose of water remediation. The interaction of glyphosate on the PNG sheet, as well as on Pt-Cu decorated PNG substrates, is investigated. The Pt4-nCun (n = 0–4) clusters, such as Pt4, Pt3Cu1, Pt2Cu2, Pt1Cu3, and Cu4, have been decorated on the PNG surface to increase the reactivity of the adsorbent toward glyphosate. The adsorption of glyphosate on the PNG surface is physisorption, indicated by the low adsorption energy and negligible charge transfer. The mixed metal (Pt-Cu) clusters play a significant role in enhancing the interactions between the adsorbate and adsorbent, leading to better results for the adsorption of glyphosate. Exothermic chemisorption is shown by all Pt4-nCun clusters decorated PNG substrates, and chemical bond formation takes place between the adsorbate and adsorbent. Various electronic properties, like electron density difference plots, give information about the adsorption behavior of glyphosate, and density of states (DOS) plots reveal that on decorating with the cluster, the substrates start exhibiting magnetic character.

Sugarcane trash ash: A low cost adsorbent for atrazine and fipronil removal from water

The sugarcane trash ash (STA) has been explored as low cost adsorbent for atrazine and fipronil removal from water. Kinetics study suggested that the pseudo second order model best explain the adsorption of both pesticides. The STA show higher adsorption of fipronil (Kd - 1267.5-3321.1) than atrazine (Kd - 137.0-1445.3) while desorption followed reverse trend with 0-2.27 and 4.83-9.32% fipronil and atrazine desorption, respectively. Isotherm model optimization suggested that the Freundlich isotherm best predict the adsorption-desoprtion behaviour of pesticides. Adsorption is highly nonlinear as 1/n values were 0.23 and 0.407 for atrazine and fipronil respectively. Adsorption decreased with increase in initial concentration of pesticide in solution. The sugarcane trash, a waste, can be used as energy source in boilers and the ash obtained can be utilized as low-cost adsorbent for pesticide removal from contaminated water.

Modulation of cytotoxicity by consecutive adsorption of tannic acid and pesticides on surfactant functionalized zeolites

This study investigated the environmental application of FAU type zeolites modified with cationic surfactants (cetylpyridinium chloride, tetrapropylammonium chloride and benzalkonium chloride). Adsorbent characterization was conducted using Fourier-transform infrared and Raman spectroscopy, thermogravimetry and differential thermal analysis, atomic force microscopy and X-ray powder diffraction. The efficiency for tannic acid adsorption from aqueous solution on the surface of prepared composites is studied and the adsorption process was modelled with different isotherm equations. Surfactant modifications of zeolites led to improved adsorption properties compared to FAU zeolites alone. The proposed mechanism controlling the adsorption of tannic acid onto surfactant modified zeolites mainly relies on π-π and hydrophobic interactions. The investigated materials are promising adsorbents for tannic acid and similar phenolics and may be important for environmental and dietary aspects of polyphenol persistence and usage. Further on, functionalized zeolites were studied for insecticide acetamiprid removal, prior to and after tannic acid retention. Promising findings of insecticide co-adsorption with tannic acid led to cytotoxicity evaluation. The cytotoxicity modulation effect of zeolites and tannic acid on acetamiprid points to the essential role of both components in insecticide toxicity reduction.

Adsorption-desorption behaviour of clomazone in Regosol and Chernozem agricultural soils

Studies of adsorption and desorption of pesticides by soils are important for understanding and predicting their fate and transmission in the environment. Considering the agricultural and environmental relevance of clomazone, its sorption?desorption behaviour was studied in two widespread Serbian agricultural soil types named Regosol and Chernozem. Both phenomena are well-described by the Freundlich equation, which shows that clomazone is generally sorbed more to organic matter than to the mineral soil fractions. Chernozem, a soil containing more of both organic matter and clay, was found to bind more, and desorb less herbicide, than Regosol. Higher desorption hysteresis obtained for Chernozem could be attributed to its larger number of high- -energy sorption sites, compared to Regosol. In both soils, the hysteresis effect increases with the rise of initial clomazone concentration in the soil-water system, while the percentage of desorbed amount during successive desorption cycles decreases. The presented adsorption?desorption study shows that soil composition plays an important role in clomazone behaviour and fate in the environment, and a significantly reduced probability of contamination of both the deeper soil layers and groundwater may be expected when this herbicide is found in humus-rich soils

Evaluating Biochar Impact on Topramezone Adsorption Behavior on Soil under No-Tillage and Rotary Tillage Treatments: Isotherms and Kinetics.

The evaluation of biochar application on the adsorption behavior of topramezone on soil under no-tillage (NT) and rotary tillage treatments (RT) has been assessed. Fourier Transform Infra-Red Spectrometry (FTIR), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller) (BET) were used for the biochar characterization. Batch experiments were carried out in a laboratory to assess the adsorption of topramezone on soil through equilibrium and kinetic modeling under biochar addition. The clay content has been found to be higher under NT (18.24 ± 0.01) than under RT (15.91 ± 0.02). The total organic carbon was higher under NT. The topramezone adsorption equilibrium reached after 8 and 12 h, for NT and RT, respectively. The kinetic and thermodynamic analyses showed the adsorption under both treatments matched with pseudo-second-order kinetic and Langmuir models, respectively. After biochar addition, the pesticide adsorption capacity (40 < 25 < 15 °C) increased with decreasing temperature suggesting an exothermic adsorption process while negative values of Gibbs free energy (ΔG); −1848.07 and −366.531 J mol−1; for the soil under NT and RT at 25 °C, respectively, indicated spontaneous adsorption. Negative entropy values (ΔS); −21.92 and −78.296 J mol−1K−1, for NT and RT, respectively, explained a decreased randomness process. The enthalpy was higher (p < 0.05) under RT (−23,274.6 J mol−1) than under NT (−1313.73 J mol−1). Conclusively, it was shown that the topramezone adsorption capacity was higher under NT, and biochar addition increased more pesticide adsorption under NT than under RT.

Fabricating efficient porous sorbents to capture organophosphorus pesticide in solution

Abstract The adsorption of organophosphorus pesticides in aqueous solution was studied in this paper, including acephate, folimat, phoxim, chlorpyrifos, dipterex, and two other pesticides carbendazim and imidacloprid. Sixteen sorbents were used in the experiments, involving zeolites, mesoporous silica and activated carbon, in order to explore how the pore structure, morphology and surface composition of the sorbent affected the liquid adsorption. Among them, MCM-22 zeolite and modified SBA-15 exhibited a high capacity of capturing carbendazim and dipterex in the solution. In order to prepare a new adsorbent with low cost and high efficiency, silica gel was coated with MgO followed by alkali corrosion, in accordance with the principle of printed circuits, to form the micro-porous sorbent with the tailored pore size and surface composition. This modified silica efficiently adsorbed the folimat and rogor in solution as expected, giving a clue for the development of specific sorbent to protect environment.

Zeolitic imidazolate frameworks: Experimental and molecular simulation studies for efficient capture of pesticides from wastewater

The agricultural drainage water represents the largest part of the contaminated water with pesticide, it was necessary to remove all pesticide from it. In this paper, two different zeolite imidazole frameworks (ZIF-67 and ZIF-8) based in two different metal ions (cobalt and zinc) was investigated. The preceding two nanoparticles adsorbents were used for the elimination of two common pesticides, prothiofos and ethion. Surprising results lie in the selectivity of pesticide toward different metal ions. The maximum adsorption capacities of prothiofos onto ZIF-8 and ZIF-67 were 366.7 and 261.1 mg g−1, respectively. Whereas in ethion; the maximum adsorption capacities were 279.3 and 210.8 mg g-1 for ZIF-8 and ZIF-67, respectively. Both pesticide adsorption followed pseudo-second-order kinetics and best fit the Langmuir adsorption model. The adsorption of ethion and prothiofos insecticides on to the surface of ZIFs were confirmed by using Fourier transform infrared (FTIR) spectroscopy and energy-dispersive X-ray spectroscopy (EDS). The adsorption of the pesticide molecules onto the ZIF surfaces was investigated in dry system using Grand canonical Monte Carlo (GCMC) simulation. The GCMC simulation provides information on the adsorption energies and maximum adsorption capacities. Molecular dynamics simulation was also revealed the effect of water solvent on the adsorption mechanism. This combination of simulations provides a complete picture of the adsorption mechanism which is needed for understanding the adsorption process of ZIF materials and the practical applications uses.

Rapid prediction of atrazine sorption in soil using visible near-infrared spectroscopy.

Sorption is an important process for determining the fate, effects, and ecological risks of pesticides in terrestrial and aquatic environments. Within a watershed, soil properties vary greatly because of landscape and management practices, leading to spatial variation of pesticide sorption coefficients (Kd). A method for the rapid determination of the sorption variability of atrazine in soils of the Baima river catchment using visible near-infrared (Vis-NIR) spectroscopy is studied in this work. Partial least square regression (PLS) was used to build calibration models. To achieve optimum models, several methods of spectral preprocessing and variable selection were investigated. The results show that the combination of standard normal variant transform (SNV) and Monte Carlo uninformative variable elimination (MC-UVE) can significantly improve the model. For validation samples, the correlation coefficient between the predicted value and the reference value determined by high-performance liquid chromatography (HPLC) analysis is 0.8090. Moreover, positive correlations are observed between the pesticide adsorption coefficient and the organic carbon (OC) and total nitrogen (TN) contents, respectively. Prediction models for OC and TN were built. The correlation coefficients of OC and TN between the predicted values and the reference values are 0.9285 and 0.6599, respectively. The results show that Vis-NIR can be used as a rapid and simple method to predict soil composition and pesticide sorption.

Magnetic solid-phase extraction of organophosphorus pesticides from fruit juices using NiFe2O4@polydopamine@Mg/Al-layered double hydroxides nanocomposites as an adsorbent

Herein, we developed a novel three-layer nanocomposite for adsorption/extraction of organophosphorus pesticides in fruit juice samples. This magnetic nanocomposite was fabricated by coating polydopamine and Mg/Al layered double hydroxides onto NiFe2O4 nanoparticles, which overcomes the shortcomings of low surface area and easy agglomeration associated with conventional Fe-based crystal nanoparticles. Additionally, the higher dispersibility of polydopamine and larger specific surface area of Mg/Al layered double hydroxides are conducive to rapid dispersion and efficient adsorption of organophosphorus pesticides by the synthesized nanocomposites, thereby greatly improving the efficiency of magnetic solid-phase extraction. The extraction method based on as-synthesized nanocomposites provided average extraction recoveries of 84.9% for methamidophos, parathion and phoxim, an increase of ca. 30% and 19% over those of NiFe2O4 and NiFe2O4@polydopamine, respectively. The main operational parameters were firstly screened and then optimized using Plackett-Burman and central-composite design, respectively. Under optimized conditions, this proposed method yielded low detection limits (0.06–0.13 μg L−1) and high intra- and inter-day precisions (2.7–4.5%). Average extraction recoveries for organophosphorus pesticides were 81.8–94.4% in grape, apple, orange, peach and mango fruit juices. To sum up, it integrates highly efficient preconcentration/extraction/dispersion, as well as rapid separation/collection into one synchronous step, satisfies the technical requirement of modern analytical pretreatment and thus enriches the multi-functional application of Fe-based nanoparticles.

Mesoporous carbon materials with different morphology for pesticide adsorption

A facile and effective co-assembly approach has been developed to controllably fabricate mesoporous carbon materials (MC) with different morphologies. 1-Alkyl-3-methylimidazolium bromide and tetraethyl orthosilicate (TEOS) are applied to assemble with resorcinol/formaldehyde resin (RF) through electrostatic interaction to produce tunable morphologies by simply changing the concentration of the reactants. The increasing in concentration of reactant led to tunable structure from irregular particle aggregates to thin sheet, fluffy spheres and then to hollow olive-like structure, which shows variable adsorption performance for pesticide wastewater treatment. MC with regular spherical morphology, dual-mesoporous structure and high surface area shows higher adsorption capacity than MC with other morphologies, proving its excellent prospects in treating pesticide wastewater.

Expanding the use of biobeds: Degradation and adsorption of pesticides contained in effluents from seed-coating, bulb disinfestation and fruit-packaging activities

Agro-food industries that use pesticides constitute significant point sources for the contamination of natural water resources. Despite that, little is known about the treatment of their pesticide-contaminated effluents. Biobeds could be a possible solution for the depuration of these effluents. In this context, we explored the degradation and adsorption of pesticides used in seed-coating (carboxin (CBX), metalaxyl-M (MET-M), fluxapyroxad (FLX), fludioxonil (FLD)), bulb-dipping (chlorothalonil (CHT), thiabendazole (TBZ), FLD) and fruit-packaging activities (FLD) in a biomixture, used as biobed packing material, and in soil. The degradation of pesticides was tested individually and in mixtures relevant to their industrial use, while FLD was also tested at different concentrations (10, 20, and 150 mg kg−1) representing its use in the different industries. CBX, FLD, and CHT, when applied individually, and all other pesticides when applied in mixtures, degraded more rapidly in biomixture than in soil. In most cases pesticides application in mixtures retarded their degradation. This was more pronounced in soil than in biomixture, especially for MET-M and FLD. CHT had the most prominent inhibitory effect on the degradation of TBZ and FLD. FLD degradation showed a dose-dependent pattern (DT50 42.4 days at 10 mg kg−1 and 107.6 days at 150 mg kg−1). All pesticides showed higher adsorption affinity in the biomixture (Kf = 3.23–123.3 g mL−1) compared to soil (Kf = 1.15–31.2 g mL−1). We provide initial evidence for the potential of the tested biomixture to remove pesticides contained in effluents produced by different agro-industrial activities. Tests in full-scale biobeds packed with this biomixture will unravel their full depuration potential for the treatment of these agro-industrial effluents.

Comparative analysis of physiochemical properties of physically activated carbon from palm bio-waste

Conversion of palm waste to activated carbon have attracted significant attention due to their lignocellulose chemistry and abundance. In the past, several palm waste has been converted to activated carbon for various applications. The highly porous material is efficient for application in gas, heavy metals, and pesticide adsorption, water purification, and as the active material of electrochemical double layer capacitor. Due to variation in the preparatory conditions, there is no adequate comparison in the electrochemical properties of palm waste derived activated carbons. In this study, palm kernel shell (PKS), oil palm fiber (OPF), and empty fruit bunch (EFB) were used to produce activated carbon by one step physical carbonization and activation at 700 °C and 1 h hold time. A comparative analysis of the physiochemical characteristics of the activated carbon is presented. XRD results reflect the amorphous nature of all the samples and BET surface area of 823 m2/g, 700 m2/g, and 592 m2/g were recorded for EFB, PKS, and OPF, respectively.

Modified magnetic chitosan nanoparticles based on mixed hemimicelle of sodium dodecyl sulfate for enhanced removal and trace determination of three organophosphorus pesticides from natural waters

Mixed hemimicelle SDS-coated magnetic chitosan nanoparticles (MHMS-MCNPs) were utilized as an efficacious adsorbent for both removal and preconcentration of pesticides named diazinon, phosalone and chlorpyrifos. In this method, the formation of mixed hemimicelles made up of SDS on the surface of MCNPs leads to solubilization and the retention of target analytes by strong hydrophobic and electrostatic interactions, which has been realized for the first time in magnetic chitosan nanoparticles support. Different parameters affecting the adsorption of pesticides were optimized as rFemoval efficiency by response surface methodology and one variable at a time. Under the optimum condition, adsorption equilibrium data were fitted well to the Langmuir isotherm. Extraction recoveries for 5 ng mL−1 of diazinon, phosalone and chlorpyrifos were 99%, 98% and 96%, respectively; with relative standard deviations values were lower than 4.6% for five replications of extraction. Limit of detection obtained for mentioned pesticides were <0.09 ng mL−1. Eventually, MHMS-MCNPs were successfully applied for both removal and trace determination of pesticides in surface and ground environmental and waste water samples collected from various places in northern Iran.

Optimizing a low added value bentonite as adsorbent material to remove pesticides from water

A local low value bentonite from Southern Spain (Raw Bentonite), previously decarbonated (Bent), was modified to improve its pesticide adsorption capacity with Fe3+, hexadecyltrimethylammonium (HDTMA) and the biopolymer chitosan (CH). Adsorption of pesticides on powdered samples showed that Fe3+ and HDTMA were appropriate modifiers for this purpose. The modification was optimized by saturation with Fe3+ (Bent-Fe) and hexadecyltrimethylammonium (Bent-HDTMA) and the obtained adsorbents were characterized by several physicochemical techniques (X-ray diffraction, thermogravimetric analysis, X-ray fluorescence, physisorption of N2). Their adsorption capacity to remove three widely used pesticides in Andalusian crops (terbuthylazine, tebuconazole and MCPA) from water was assessed and compared with the commercial organoclay Cloisite® 10A (Clo10). The modified bentonites adsorbed the selected pesticides in a percentage ranging from 30 to 100%, whereas sorption on Clo10 ranged from 30 to 90%. For their possible use as filtering beds, Bent-HDTMA, Bent-Fe and Clo10 were granulated by using three different binders (colophony resin and carnauba and bee waxes) at three different mixing ratios and the water resistance and pesticide adsorption of the granules were measured. Results showed that the granulation process did not alter the pesticide adsorption capacity of the powdered modified bentonites, and both waxes granules (carnauba and bee wax) showed better behavior than resin granules. In this work, we succeeded in the preparation of granulated adsorbents derived from a low cost material with similar behavior against a high purity smectite (precursor of Cloisite® 10A). This raises an alternative for this waste material to be used in filter systems for removing pesticides from contaminated water.

Effect on herbicide adsorption of organic forestry waste products used for soil remediation

Organic soil amendments can be useful for improving degraded soil, but this increase in organic matter (OM) may influence adsorption of herbicides subsequently applied to the treated soil, even though the particle size of amendments and their nature differ from typical soil OM. In this study, a batch equilibrium method was used to measure adsorption of five herbicides following application to two organic media, wood pulp and sawdust, comparing these with two cropping soils. Herbicide adsorption, quantified by distribution coefficients (kd), was much higher in the two organic media than in the cropping soils. The increases in adsorption were strongly correlated to the percentage of organic carbon. When the kd was normalized to adsorption coefficients corrected for OM content (koc), variation in results between the media was greatly reduced, indicating that OM is an important factor influencing adsorption in these media. The results of this study suggest that herbicides will be less effective when applied to soils in which sawdust and wood pulp have been added. Using organic amendments to remediate soil will increase adsorption of pesticides, reducing their bio-availability and efficacy, but also reducing their tendency to leach into root zones of deep-rooted crops and into groundwater.

Synthesis, Characterization of Metal-Schiff Base Functionalized Mesoporous Silica for Pesticide Adsorption

Synthesis, Characterization of Metal-Schiff Base Functionalized Mesoporous Silica for Pesticide Adsorption

Synthesis, Characterization of Metal-Schiff Base Functionalized Mesoporous Silica for Pesticide Adsorption

The mesoporous silica modified by salicylaldimine was prepared through a co-condensation method. Through the bridge effect from metal ion (copper ion, zinc ion, manganese ion), the model drug-avermectin was supported on the metal-Schiff base functionalized mesoporous silica (M-MCM-41) to form a highly efficient adsorbents for pesticidedelivery and removal. The experimental results showed that the sequence in adsorption capacity (AC) for avermectin (AVM) of various mesoporous silica in different adsorption time was Zn-MCM-41 > Cu-MCM-41 > Mn-MCM-41 > MCM-41 > SA-MCM-41. The AC of Zn-MCM-41 was 151 mg/g, while the MCM-41 was 78 mg/g which increased nearly 100 % after modification due to its strongest coordination ability. The FT-IR and XPS results confirmed the existence of coordination bond between SA-MCM-41 and metal ions as well as the coordination bond between M-MCM-41 and avermectin. The kinetic data and the equilibrium isotherms are modeled by three kinetic models, the pseudo-first-order, the pseudo-second-order and intraparticle diffusion, and two isotherm models, Langmuir and Freundlich, respectively. The kinetic mechanism of the adoption changed from physical adsorption to the intraparticle diffusion due to the stronger interaction between avermectin and the mesoporous silica through coordination. Adsorption isotherm of the samples were well-represented by Freundlich model which indicated that the adsorption was reversible.