Environmental Nanotechnology, Monitoring and Management最新文献

Phytogenic, also known as plant-based microemulsions (MEs) are adaptable and sustainable nanosystems that are extensively employed in food science, biotechnology, detergents, medicine delivery, and cosmetics. These liquid colloidal systems are distinguished by their tiny size, usually less than 100 nm. They are less viscous, optically transparent, thermodynamically most stable formulations and facilitate to administer both hydrophilic and lipophilic drugs of interest because of their enhanced bioavailability, absorption behavior, capacity to emulsify weakly water-soluble compounds, and enhanced shelf life. Phytogenic microemulsions address the limitations of conventional insecticides, which typically have poorly water-soluble active ingredients, harm the environment, human health, and non-target organisms, and foster resistance in targeted species. Therefore, phytogenic microemulsions are regarded as excellent and safe delivery systems for insecticidal formulations. This instructional review offers a thorough insight of the current status of the MEs as novel drug delivery systems against the vectors, agricultural pests, and insects of major concern thereby addressing global challenges. Therefore, the objective of this study is to provide an overview of the formulation, characterization, and applications of MEs across diverse domains, with a particular emphasis on their effectiveness against insect pests and vectors.

The challenge of eliminating heavy metal ions from water has been addressed using Polysulfone (PSf) membranes, which have demonstrated significant potential in treating contaminated solutions. This research aimed to improve the permeability and separation performance of PSf membranes by incorporating Al₂SiO₆ into their structure. The introduction of Al₂SiO₆ into the membrane matrix was achieved through the nonsolvent-induced phase separation (NIPS). The resulting mixed-matrix membrane (MMM) exhibited improved efficiency in water filtration. The inclusion of Al₂SiO₆ led to desirable changes in membrane properties such as hydrophilicity, contact angle and porosity, thereby enhancing the performance of heavy metal ion removal capability. Under a pressure of 2 bar, the mixed matrix membranes achieved rejections exceeding 95 % for lead and 70 % for arsenic. Furthermore, the occurrence of Al₂SiO₆ enhanced the anti-fouling assets of the PSf membrane by increasing its hydrophilic nature and facilitating the development of a hydration layer, which tends to prevent the interactions between the membrane surface and foulant. These properties make these membranes suitable candidates for separating toxic ions from water.

The synthesis of high-quality nanomaterials by different of methods have been developed through physical, chemical, biological, microbial, green synthesis, coprecipitation, hydrothermal treatment, flame pyrolysis, and biogenic reduction processes. The nanomaterials produced have offered substantial benefits to society through their successful implementation in numerous fields, such as food safety, transportation, energy, catalysis, medicine, antimicrobial, anticancer, antioxidant nanodrugs, vaccines, capacitors, fuel cells, and batteries. Many hazardous effects have been reported due to chemical synthesis, so the potential utility of nanomaterials is also recognized in environmental management,as there is growing demand to control diverse pollutants. At present, there is a green synthetic route for the development of nontoxic and eco-friendly materials in a sustainable manner. The main objective of this review is to provide a perspective overview by comparing green versus chemical synthesis methods concerning the types, advantages, disadvantages, and persistent solutions for extermination caused by toxic nanoparticle production methods.

Polycyclic aromatic hydrocarbons (PAHs) are potential hazards and are often found in aquatic environments through industrial effluents. Herein, we report sulfonated modified mesoporous thermoplastic polymers to remove potentially carcinogenic PAHs from water rapidly. Mesoporous structures of the thermoplastics (polystyrene, polysulfone, and polycarbonate) were attained using nano-crystallization induced phase separation by flash-freezing route. Sulfonation reactions carried out hydrophilic surface modifications of the polymers. Their ion exchange capacity (IEC) values determined the degree of sulfonation. The sulfonated mesoporous polymers were characterized using Fourier-Transform Infra-Red spectroscopy (FT-IR) for functional groups, Field-Emission Scanning Electron Microscopy (FE-SEM) for mesoporous structures, Brunauer-Emmet-Teller method for specific surface area, and Barrett-Joyner-Halenda method for pore size distributions. The IEC values for the sulfonated mesoporous polymers range from 1.13 – 1.15 × 10^-2 meq. g⁻¹. The sulfonated mesoporous polymers showed high specific surface areas (176–185 m²/g) with pore sizes ranging from 5 nm to 9 nm. The sulfonated mesoporous polymers rapidly adsorb PAHs from nearly saturated water solutions within 60 min with % removal of over 98 %. The adsorbents can also be easily regenerated by simple washing with methanol and are found to be recycled up to 10 cycles with only a marginal reduction in adsorption capacities.

The presence of antimicrobial sulfa chemicals in water is becoming a more serious problem and action must be taken to create an effective decontamination process for wastewater treatment. In this way, current thinking has focused on removing sulfa drugs as broad-spectrum antimicrobials from water by metal organic framework ((Cu&Co)-benzenetricarboxylate, M−BTC) bound within the amberlite polymer. Here, M(Cu&Co)-BTC is synthesized and incorporated within amberlite polymer in a single step. Moreover, the adsorptive capacities of the various sulfa drugs (sulfamethazine and sulphanilamide) were investigated using M−BTC@amberlite compounds for the first time. The adsorption efficiency of the sulfa drugs was monitored (higher performance for sulfamethazine rather than sulfanilamide), and the adsorption uptake was reached 99 % within about 60 min. The adsorption isotherms were best fitted using the Langmuir and pseudo-second-order model, individually. The greatest potencies for Cu-BTC@amberlite and Co-BTC@amberlite were 205 and 306 mg/g for sulfamethazine and 326 and 488 mg/g for sulfanilamide, separately. By incorporating Co-BTC within amberlite, the absorption capacity of sulfamethazine and sulfanilamide was extended by 1.72 and 1.83 times, respectively, while incorporation of Cu-BTC within amberlite, the adsorption capacity of sulfamethazine and sulfanilamide was extended by 2.56 and 2.73 times, respectively. The attached MOFs with polymer showed very high reusability and their efficacy in uptake of sulfamethazine and sulfanilamide diminished by 14.8–15.9 % and 11.3–12.7 %, separately, after five sequential adsorption cycles. Hence, in agreement with the adsorption result, a conceivable tool is proposed. The sulfa drug adsorption performed on a range of BTC-MOFs with diverse physicochemical properties and point-by-point characterization confirmed that the highest adsorption capacity of MOFs is achieved through bi-bi interaction; H-bonding between NH sites of sulfa drug particles and O sites of carboxyl units within MOFs. In scale-up, M−BTC@amberlite has demonstrated remarkable reusability, which is enticing for potential applications in the adsorption of sulfa drugs from wastewater.

Fouling remains a major challenge in membrane-based water treatment technologies. As a result, contemporary research is geared towards membrane surface modification techniques to reduce fouling. Mitigation strategies involving incorporation of nanoparticles (NPs) into polymeric membranes has gained a remarkable interest. However, NPs leach is eminent, particularly with poor support on membranes resulting in secondary pollution. Consequently, aquatic life is threatened depending on the level of toxicity of the leached NPS. Also, these NPs present toxicological effects to other water consumers. Therefore, this work reviews contemporary literature on membrane surface modification techniques paying attention to incorporation of NPs in the membrane polymer matrices. Various factors governing NPs leach are concisely presented. Special attention was focused on stability of the NPs immobilization on the polymeric membrane due to thermodynamic interactions. Similarly, the effects of NPs leach on membrane physicochemical properties and the NPS ecotoxicity are discussed in detail based on literature reports. Different approaches presenting improvement on NP stability in the polymer matrix are discussed. Lastly casting of future perspectives and the impact of NP leach on sustainable performance of the membranes and ecotoxicity is presented.

Removal of cerium from environmental and aqueous streams is essential in waste water rejuvenation processes. Nitrogen modified graphene nano walls (N-GNWs) have shown ultra-high sorption efficiency of trivalent cerium from aqueous medium (K_d > 2 × 10⁷) and a large sorption capacity of ∼ 2500 mg/g is achieved. N-GNWs were deposited on carbon paper substrate using PECVD technique. The three-dimensional nature of N-GNWs are revealed from high resolution FESEM images. Raman spectroscopic studies have shown that GNWs are defective and possess a few layer graphene like structure. Secondary Ion Mass Spectroscopic studies of the Ce sorbed N-GNWs and optical emission spectroscopy of the residual solution confirm the sorptive retrieval of cerium. Visual Minteq based ionization model is introduced to explain high (>90 %) sorption of Ce at pH≥7 and the mechanistic aspects of sorption for standard Cerium solution is discussed. The sorption involves attachment of cerium hydroxyl ions to the active cites on the sorbent surface.

The industrial use of plastic materials has led to the production of microplastics, posing significant environmental risks. Microplastic pollution, especially in water systems, has prompted efforts to develop effective removal methods. Therefore, the purpose of this study is devoted to accomplish a novel comparative assessment analysis for the efficacy of two distinct nanosized biochars in removal of polystyrene microplastics (PS-MPs) from aquatic systems by using the batch removal mode. The two selected nanosized biochars, denoted as PAB-NB and AL-NB, were derived from the pyrolysis of pineapple peels and artichoke leaves, respectively. Characterization techniques confirmed the composition and surface properties of the nanobiosorbents. Results showed that both PAB-NB and AL-NB exhibited efficient removal of PS-MPs, with AL-NB demonstrating slightly higher removal capacity. Adsorption processes were found to follow Langmuir monolayer and Freundlich multilayer formations on PAB-NB and AL-NB, respectively. Kinetic studies suggested pseudo1st and pseudo-2nd order models for AL-NB and PAB-NB, respectively. At pH 2.0, both nanobiosorbents showed high removal rates, indicating neutralization of surface charges. These findings suggest that renewable nanobiosorbents derived from biomass wastes, free from metallic contaminants, hold promise for effective removal of polystyrene pollutants, offering a sustainable solution to prevent microplastic pollution in water systems.

In today’s world of public health, the rise in chronic illness and the contamination of the environment due to heavy metal ions are two major problems. Particularly, one extremely harmful contaminant, mercury(II), damages the immune system, central nervous system, and human metabolism, posing a serious risk to life systems. Given the extreme toxicity of mercury to people, it is critical to develop a quick, precise, affordable, and reliable techniques for estimating the amounts of Hg²⁺ in biological and environmental samples. A number of methods, including the colorimetric assay that is reviewed here, can be used to monitor mercury levels. Nanomaterials, polymers, porous materials, and nanocomposites are examples of advanced functional systems that have garnered a lot of attention lately due to their real-time detection, speedy removal, outstanding anti-interference, fast reaction time, high selectivity, and low detection limit capabilities.

This study investigates soil contamination around existing municipal solid waste (MSW) management facilities specifically, composting, and active landfill sites in Bangalore, India. The physicochemical parameters considered are pH, electrical conductivity (EC), sodium adsorption ratio (SAR), and concentration of heavy metals namely copper (Cu), chromium (Cr), nickel (Ni), and zinc (Zn). Soil samples collected from MSW sites and natural soil, are chemically analysed in laboratory. A comparison of parameters was done by designing and testing 28 statistical hypotheses.

This empirical study revealed that the concentration order of heavy metals was Zn > Cr > Cu > Ni for landfill site samples and Zn > Cu > Cr > Ni for composting site samples. The mean values of pH, SAR, Cu, Cr, Zn, Ni, and EC in landfill site samples were higher than that control samples by 21 %, 60 %, 152 %, 4 %, 131 %, 114 %, and 555 % respectively. Similarly, for composting site samples, the mean values of pH, SAR, Cu, Cr, Zn, Ni, and EC were higher than that control samples by 13.61 %, 108 %, 1088 %, 5 %, 374 %, 236 %, and 2144 % respectively. Heavy metals concentrations, EC, and SAR in composting site samples exceeded control and landfill site samples. However, pH of landfill site samples was higher than that in both composting site and control samples. While the Cr concentrations among the three sites was not statistically significant, it was highest in composting site samples. The study recommends measures to obviate soil contamination from existing MSW management facilities.