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.
The increase of production and consumption persistently introduce different pollutants into the environment. The constant development and improvement of analytical methods for tracking environmental contaminants are essential. The demand for high sample throughput analysis has hit the spotlight for developing selective sensors to avoid time-consuming sample preparation techniques. In addition, the sensor’s sensitivity should satisfy the rigorous demands of harmful compound tracking. Molecularly imprinted plasmonic-based sensors are excellent candidates to overcome selectivity and sensitivity issues. Molecularly imprinted polymers are robust, stable in aqueous and organic solvents, stable at extreme pHs and temperatures, and include a low-cost synthesis procedure. Combined with plasmonic-based techniques, they are the perspective choice for applications in the field of environmental protection. Plasmonic-based sensors offer a lower limit of detection, a broad linearity range, high sensitivity, and high selectivity compared to other detection techniques. This review outlines the optical plasmonic detection of different environmental contaminants with molecularly imprinted polymers as sensing elements. The main focus is on the environmental pollutants affecting human and animal health, such as pesticides, pharmaceuticals, hormones, microorganisms, polycyclic aromatic hydrocarbons, dyes, and metal particles. Although molecularly imprinted plasmonic-based sensors currently have their application mostly in the biomedical field, we are eager to point them out as a highly prospective solution for many environmental problems.
Growing pollution is making it necessary to find new strategies and materials for the removal of undesired compounds from the environment. Adsorption is still one of the simplest and most efficient routes for the remediation of air, soil, and water. However, the choice of adsorbent for a given application ultimately depends on its performance assessment results. Here, we show that the uptake of and capacity for dimethoate adsorption by different viscose-derived (activated) carbons strongly depend on the adsorbent dose applied in the adsorption measurements. The specific surface areas of the investigated materials varied across a wide range from 264 m2 g−1 to 2833 m2 g−1. For a dimethoate concentration of 5 × 10−4 mol L−1 and a high adsorbent dose of 10 mg mL−1, the adsorption capacities were all below 15 mg g−1. In the case of high-surface-area activated carbons, the uptakes were almost 100% under identical conditions. However, when the adsorbent dose was reduced to 0.01 mg mL−1, uptake was significantly reduced, but adsorption capacities as high as 1280 mg g−1 were obtained. Further, adsorption capacities were linked to adsorbents’ physical and chemical properties (specific surface area, pore size distribution, chemical composition), and thermodynamic parameters for the adsorption process were evaluated. Based on the Gibbs free energy of the adsorption process, it can be suggested that physisorption was operative for all studied adsorbents. Finally, we suggest that a proper comparison of different adsorbents requires standardization of the protocols used to evaluate pollutant uptakes and adsorption capacities.
Coffee is one of the most popular beverages, with around 10.5 million tons manufactured annually. The same amount of spent coffee grounds (SCGs) might harm the environment if disposed of carelessly. On the other hand, pesticide contamination in food and biowaste is a rising problem. Because pesticides are hazardous and can cause serious health consequences, it is critical to understand how they interact with food biowaste materials. However, it is also a question if biowaste can be used to remediate rising pesticide residues in the environment. This study investigated the interactions of SCGs with the organophosphate pesticides malathion (MLT) and chlorpyrifos (CHP) and addressed the possibility of using SCGs as adsorbents for the removal of these pesticides from water and fruit extracts. The kinetics of MLT and CHP adsorption on SCGs fits well with the pseudo-first-order kinetic model. The Langmuir isotherm model best describes the adsorption process, giving the maximal adsorption capacity for MLT as 7.16 mg g−1 and 7.00 mg g−1 for CHP. Based on the thermodynamic analysis, it can be deduced that MLT adsorption on SCGs is exothermic, while CHP adsorption is an endothermic process. The adsorption efficiency of MLT and CHP using SCGs in a complicated matrix of fruit extracts remained constant. The neurotoxicity results showed that no more toxic products were formed during adsorption, indicating that SCGs are a safe-to-use adsorbent for pesticide removal in water and fruit extracts.
Due to the accumulation of pesticides in the environment, the development of efficient strategies for their removal is of utmost importance. Activated carbons are currently seen as excellent candidates for adsorptive pesticide removal based on several beneficial properties, like a large surface area, developed porosity, and low price. However, a deep link between materials' properties and performance is still elusive. Here we focus on the kinetics of three organophosphate pesticides removal, aliphatic dimethoate and malathion and aromatic chlorpyrifos, using a series of carefully prepared activated carbon fibers. Used adsorbents have a wide range of specific surface areas, pore size distributions, and elemental content, allowing the establishment of the link between physicochemical properties and their performance as adsorbents. We use data analysis tools to link these properties and discuss their different roles in the removal of three structurally different yet extremely dangerous pesticides. The obtained results can guide the synthesis of novel adsorbents or rationally select adsorbents for specific target pollutants based on the physicochemical properties of adsorbents and the chemical structure of pollutants.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.