International Journal of Environmental Science and Technology最新文献

In this study, response surface methodology (RSM) and artificial neural networks (ANNs) were used to establish an approach for evaluating heavy metal adsorption processes. Shell powder (CP) was used as an environmentally friendly and economical adsorbent for nickel removal.

The adsorbent was then characterized by Fourier transform infrared spectroscopy (FTIR). The effect of operational parameters influencing the adsorption capacity of an inorganic pollutant (nickel) by a natural adsorbent (CaCO₃) in the context of aquatic remediation, such as pH, temperature, contact time, initial metal concentration, adsorbent dose, and stirring speed, was investigated using a Box-Behncken design of experiments (BBD). This same design was also used to obtain a training set for the ANN.

The results showed that the adsorbent (PC) improved the nickel adsorption capacity. Both the RSM and ANN models accurately predicted nickel adsorption, with correlation coefficients of 0.999 and 0.788, respectively. The RSM model proved more accurate, exhibiting the lowest root mean square error (RMSE). An optimal adsorption efficiency of 86.85% was achieved for 2.84 g of shell powder (SSP) at pH 5.95, a mass of 2.84 g, a temperature of 334 K ± 2, a contact time of 79.85 min, and a nickel ion concentration of 207.95 ppm. Furthermore, FTIR analysis of the shell powder confirmed the presence of broad bands characteristic of the (C = O) group, one at 1631.7 cm⁻¹ and the other at 3467.8 cm⁻¹.

This study aimed to develop an environmentally friendly hybrid nano-adsorbents for removing nickel ions (Ni (II)) from aqueous solutions. Mesoporous silica Santa Barbara Amorphous-15 (SBA-15) and silica‐coated magnetic iron oxide nanoparticles (Fe₃O₄@SiO₂) were synthesized using co-precipitation and sol–gel (Stöber) methods, respectively. These particles were then functionalized with ethylene-diamine-tetra-acetic acid (EDTA) as a chelating ligand and 3-aminopropyl triethoxysilane (APTES) as a spacer. The resulting hybrid nano-adsorbents were evaluated for its ability to remove Ni (II) from aqueous solutions, leveraging Ni (II) strong affinity for the oxygen and nitrogen donor atoms in EDTA. The adsorbent’s particle size, morphology, surface area, and successful functionalization were confirmed using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), vibrating sample magnetometry (VSM), and transmission electron microscopy (TEM). These characterization results verified the successful synthesis and functionalization of SBA-15 and Fe₃O₄@SiO₂ with amine (–NH²) groups from APTES and carboxyl (–COO) groups from EDTA. Adsorption isotherms were analyzed using Langmuir and Freundlich models. The adsorption of Ni (II) on the two adsorbents at 25 °C is best described by the Freundlich isotherm model. According to the correlation coefficient (R²) values 0.964 and 0.999 for Fe₃O₄@SiO₂-EDTA and SBA-15-EDTA, respectively. Moreover, SSE values 0.053 for Fe₃O₄@SiO₂-EDTA and 1.894 for SBA-15-EDTA, the pseudo 2nd model is the most appropriate model to depict the dynamics of the adsorption process. The maximum adsorption capacity was 20.8 mg/g for Fe₃O₄@SiO₂-EDTA and 178.5 mg/g for SBA-15-EDTA.

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Plastic waste has been a critical environmental concern because of its strong resistance to natural degradation. In this study, a sustainable myco-nanocatalytic approach was developed for plastic waste degradation using Al₂O₃ nanoconjugates mediated by Ganoderma lucidum extract. The bioactive compounds from G. lucidum were extracted under optimized conditions. Among the four methods of NCs synthesis, the solvent-mediated synthesis route produced stable NCs than conventional wet chemical methods. Surface Plasmon Resonance confirmed the formation of Al₂O₃ NCs at 325 nm. Fourier transform infrared spectroscopy revealed that fungal phytochemicals acted as stabilizing agents, with characteristic Al–O lattice vibrations observed between 1363 and 1143 cm⁻¹. X-Ray diffraction peaks at 43.74° and 48.86° indicated crystalline α- and γ-Al₂O₃ phases. Scanning electron microscopy showed uniform aggregates, verifying nanoscale morphology. The catalytic efficacy of the GL-Al₂O₃ NCs in degrading raw plastic waste was demonstrated across three different environmental samples. Among them, the manhole sample exhibited the most effective degradation, evidenced by significant UV–Vis absorption decrease from 0.468/0.268 (control) to 0.083/0.087 (GL-Al₂O₃ NCs) at 340 and 290 nm, respectively. Cantt. and Mochi Bagh Drain samples followed a similar trend, though slightly lower as compared to the Manhole sample. The metallurgical microscopic outcomes showed surface disruptions across all three samples, which further supported the degradation potential of GL-Al₂O₃ NCs. The study demonstrated an economical, environment friendly, and highly effective approach for plastic degradation under mild conditions using a fungal extract-mediated Al₂O₃ NCs, showing clear surface deterioration and highlighting NCs' potential for sustainable waste management.

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This study investigates a low-cost and sustainable approach for decentralized wastewater treatment using locally available filtration materials such as sand, red brick, and marble waste. The main objective was to evaluate the purification and decontamination efficiency of these materials for secondary effluents from urban wastewater treatment. Experimental results revealed that red brick and marble filters achieved outstanding pollutant removal, with reductions of 86.58% for COD, 86.59% for BOD₅, 84.6% for NH₃-N, 64% for orthophosphate, 99.11% for TSS, 97.31% for fecal coliforms, 99.51% for total coliforms, and 93% for Escherichia coli. Remarkably, these performances were obtained with a short hydraulic retention time (HRT) of 45 min, which is significantly lower than that reported in similar infiltration–percolation systems (Borrego-Limón et al. in Environ Technol Innov 30:103016, 2025a; Borrego-Limón et al. in Processes 13:2564, 2025b; Saeed & Sun in Environ Sci Pollut Res 27:1–11, 2020; Sirianuntapiboon et al. in Sci Asia 32:309–314, 2006). The high efficiency achieved within such a short contact time demonstrates the synergistic effect of red brick’s porous structure and marble’s alkalinity, enhancing both physico-chemical and microbial removal processes. The treated effluent met the quality standards for agricultural reuse, promoting circular economy principles through the valorization of construction waste materials. This work highlights a green and efficient strategy to improve wastewater treatment sustainability in resource-limited contexts.

As vital components of urban green infrastructure, city parks play a crucial role in regulating the local climate. However, studies in severely cold regions have mainly focused on summer cooling effects, with limited attention to year-round thermal dynamics. This study examines 35 urban parks in Hohhot, China (≥ 3 ha), using seasonal land surface temperature data derived from Sentinel-2, Shuttle Radar Topography Mission, and Landsat imagery (March 2022–February 2025). The attenuation gradient of park-cooling intensity was quantified within 0–300 m concentric buffers to assess seasonal variations in thermal regulation. Given the strongest cooling observed in summer, the influence of landscape characteristics—area, perimeter, shape index, green space proportion, and water surface proportion—was further analyzed using Pearson correlation.

Results indicate that (1) stable cooling effects occurred in spring, summer, and autumn, with the strongest in summer (mean reduction 2.56 °C) and an effective cooling radius up to 90 m, while no significant effect appeared in winter; (2) summer temperatures were weakly related to geometric factors but strongly linked to surface composition, showing negative correlations with vegetation coverage and green space proportion, and positive correlations with impervious surfaces; and (3) larger parks expanded cooling extent, with vegetation and water enhancing cooling and impervious surfaces reducing it. These findings reveal the seasonal dynamics and scale thresholds of urban park cooling in severely cold regions, providing scientific guidance for climate-responsive and sustainable park planning.

Arid and semi-arid regions present unique opportunities to explore how irrigation water quality interacts with diverse soil characteristics. This study assesses interactions between irrigation water quality and saturated hydraulic conductivity (K_S) as well as soluble and exchangeable phases within the soils in western Iran. Twenty disturbed soil samples from agricultural lands were poured into three replicates up to a height of 10 cm inside glass columns, then leached with three solutions classified as C3S1, C4S3, and C4S4 for up to 20 pore volumes. The pH, electrical conductivity (EC), sodium absorption ratio (SAR), and exchangeable sodium percentage (ESP) increased in soils after leaching with these three solutions, while the levels of exchangeable Ca²⁺ and Mg²⁺ decreased. Increasing the SAR of the leaching solutions did not decrease K_S in the study soils because the EC levels of these solutions increased simultaneously. Clay content, organic matter (OM), cation exchange capacity (CEC), along with exchangeable Ca²⁺ and Mg2⁺ negatively correlated with K_S. However, sand exhibited a positive correlation with this parameter. Soils containing higher amounts of clay, OM, and CEC were less affected by sodification. Following leaching with different solutions, sandy loam textural class displayed the highest ESP values. As a result, it was found that soil texture plays a significant role in altering the ESP and K_S values in arid and semi-arid soils. Therefore, attention should be given to soil texture when using poor-quality irrigation water.

Soil microbial communities are fundamental to nutrient cycling, bioremediation, and soil stabilization, all of which underpin environmental sustainability. However, land-use changes and environmental stressors, particularly soil compaction, can disrupt native microbial diversity and function. This study investigated the impact of seasonal variation and compaction effect on microbial community composition within clay-rich baseliners at the Pulau Burung sanitary landfill. Baseliner samples were collected during both dry and rainy seasons at a 30 cm depth in biological replicates. Amplicon sequencing of the 16S ribosomal ribonucleic acid (16S rRNA) gene revealed dynamic microbial shifts across seasons at a 98% similarity threshold. Genus-level ternary plot analysis demonstrated seasonally distinct microbial profiles: dry season samples exhibited unbalanced, highly variable communities, while rainy season samples presented more balanced compositions dominated by key genera. Across seasons, consistently dominant genera included Collinsella, Soehngenia, Thermomonas, Acidiphilium, Fusicatenibacter, Polynucleobacter, Thermovirga, Hydrocarboniphaga, Thiolamprovum, Longimycelium, Ottowia, Pseudorhodobacter, Actinospica, Acidothermus, and Vitellibacter, indicating stable core taxa with potential functional roles in the compacted liner microbiome. Despite visible seasonal taxonomic shifts in microbial diversity and structure, PERMANOVA showed no significant effect (p > 0.05), indicating compaction and seasonal fluctuations as key drivers. Topological Data Analysis using the Ball Mapper algorithm alongside conventional statistical methods revealed no correlation between leachate and the baseliner's physicochemical parameters, confirming the environmental containment efficacy of the baseliner. Spatial heterogeneity in microbial diversity reflected microenvironmental influences shaped by compaction stress. The study focused on the impact of compaction and seasonal variation on microbial communities in engineered environments, emphasizing the need to preserve diversity for baseliner and soil health and providing insights for sustainable land-use and ecosystem management.

The aim of this work is to critically discuss the feasibility of the implementation of electrochemical processes for the treatment of offshore oilfield produced water, including insights, gaps, challenges and opportunities. The main novelty of this article is the literature-based analysis of the benefits of applying electrochemical processes to produced water treatment, considering their implementation at different stages of the conventional treatment flow already adopted on oil platforms. In addition, the advantages and limitations reported in the literature are discussed when these processes are integrated with other technologies, such as membrane filtration and other advanced oxidation methods. Based on the comprehensive analysis performed, it can be stated that electrochemical processes represent a highly efficient method to reduce the content of organic contaminants and oils in oilfield produced water, although challenges such as the formation of chlorinated by-products still need to be overcome. The combination of electro-oxidation reactions and electrocoagulation processes emerge as an alternative to the disadvantageous formation of gaseous products by adjusting the operational conditions. In addition, coupling electrochemical processes with other treatment technologies has been shown to reduce oil and grease content by more than 90%, depending on feedwater characteristics and process configuration. Finally, this work emphasizes the need for further research at pilot and industrial scales to validate not only the economic but also the environmental viability of these technologies. This is crucial to advancing their technology readiness level, achieving up to large-scale applications.

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Heavy metals are toxic, non-biodegradable pollutants that can persist in the environment and pose serious threats to human health and aquatic ecosystems. Industrial discharge of heavy metal-containing effluents continues to degrade water quality, highlighting the urgent need for effective and sustainable remediation methods. Among various techniques, adsorption stands out for its high efficiency, low cost, and reusability. Chitosan, a biopolymer derived from renewable and abundant sources, has gained significant attention as a promising biosorbent for heavy metal removal. However, its poor acid stability and limited number of active adsorption sites can hinder its performance. This review discusses recent advancements aimed at enhancing chitosan’s adsorption capacity and stability, focusing on three main strategies: (i) structural modification via crosslinking and grafting, (ii) selectivity improvement using the Hard and Soft Acid–Base (HSAB) theory, and (iii) optimization of operational parameters such as pH, contact time, and metal ion concentration. In addition, the adsorption mechanisms, including complexation, electrostatic interactions, and ion exchange, along with breakthrough curve analysis are explored to understand dynamic adsorption behavior. Importantly, this study also covers regeneration techniques, evaluating the reusability of modified chitosan across multiple cycles, cost analysis to assess economic feasibility, and findings from pilot-scale studies that demonstrate real-world applicability. Overall, this review provides a comprehensive guide for the development of efficient, cost-effective, and scalable chitosan-based adsorbents, contributing to the advancement of sustainable heavy metal remediation technologies.

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