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Gold, as a critical material with both financial and industrial value, is widely used across numerous fields such as finance, aerospace and medical care. Under the global background of increasing geopolitical risks and the advancement of high-tech industries, the demand for gold continues to grow steadily. The main raw materials for extracting gold are mainly divided into ore and electronic waste. Currently, conventional cyanidation remains the dominant industrial method for gold recovery. However, issues such as pollution and high toxicity of cyanide tailings are driving global efforts to explore environmentally friendly alternatives. Therefore, the development of green and efficient gold extraction technology has become a global research hotspot. This article focuses on cyanide-free leaching technologies, providing a detailed review of their current developments, advantages, and limitations, and proposing future trends in gold extraction. The future development directions of gold extraction include the development of thiosulfate–glycine leaching systems, the combination of multi-technology collaborative processes such as ultrasonic assistance and biological treatment to enhance efficiency, the strengthening of microbial metallurgy technology, and the construction of a resource recycling system for electronic waste. This review provides new insights and development directions for extracting gold for sustainable development. Full article

This study analyzes a balanced panel of 41 Yangtze River Delta cities from 2006 to 2021 to assess whether and why economic growth has decoupled from industrial pollution. Furthermore, this study proposes a two-dimensional decoupling framework that combines Tapio elasticity with development stages, quantifies driver contributions using an LMDI–Tapio decomposition, and estimates spatial β-convergence in pollution intensity. Key findings include the following: (1) By 2021, all YRD cities exhibit decoupling, with heterogeneity across pollutants and cities. (2) Technological progress effect is the dominant enabler of decoupling, while economic development poses a significant barrier. (3) Industrial sulfur dioxide, smoke and dust intensity, and the composite industrial pollution index show notable spatial β-convergence, with smoke and dust intensity converging most rapidly. The results inform technology-focused policies and cross-city coordination in the YRD. Full article

With the rapid development of the edible fungus industry, the environmental pressure and resource waste caused by the massive generation of fungal residue have become increasingly prominent. Meanwhile, heavy metal wastewater pollution and the growing demand for clean energy pose dual challenges to sustainable development. This study focuses on Auricularia cornea var. Li. fungal residue, exploring the establishment of a multi-level resource utilization pathway integrating “porous carbon material preparation—heavy metal adsorption—photocatalytic hydrogen evolution.” Firstly, the Auricularia cornea var. Li. residue-based porous carbon material was examined by combining hydrothermal carbonization, activation and slow pyrolysis. In optimal conditions, the porous carbon obtained yielded a surface area of 675.56 m²/g and formed a composite pore structure consisting of micropores with coexisting micropore and mesopore. Secondly, we performed batch adsorption experiments to study the effects of solution pH, adsorbent dosage and contact time and the adsorption behavior via fitting adsorbing kinetic models. Under optimal conditions, Cd(II) removal efficiency reached 92.36% and an equilibrium adsorption capacity of 92.47 mg/g. We used Cd(II) adsorbed porous carbon as a cadmium source and converted into a CdS photocatalyst using a hydrothermal sulfidation process. The CdS prepared using sodium sulfide as a sulfur source gave an average hydrogen evolution rate of 668.01 μmol·g⁻¹·h⁻¹ and showed higher photocatalytic performance for water splitting to produce hydrogen. Full article

Heavy metal contamination in soil and the resulting groundwater pollution are common at many brownfield sites. Soil washing, which dissolves contaminants into a washing solution to separate them from the soil matrix, has emerged as a promising remediation strategy. This study assessed the feasibility of applying soil washing to Pb-contaminated soil collected from an industrial area within the Trieste Port Authority (Italy) through a series of leaching tests. Batch tests were conducted using ethylenediaminetetraacetic acid (EDTA)-based extractants combined with various reducing agents to identify the most effective and environmentally sustainable washing solution. The results show that coupling EDTA with hydroxylamine hydrochloride or sodium dithionite significantly enhanced Pb solubilisation compared with EDTA alone, with dithionite emerging as the most suitable reducing agent due to its lower toxicity and reduced environmental impact. Sequential extraction tests revealed that up to 50% of total Pb could be removed after repeated washing cycles. Column leaching tests further confirmed the high efficiency of the EDTA–sodium dithionite system, achieving Pb removal rates of approximately 70% under continuous flow conditions. Overall, the results demonstrate that EDTA combined with low-dose sodium dithionite provides an effective and practical remediation strategy for heavily polluted industrial soils. Full article

In response to the dual pressures of energy consumption and environmental pollution faced by the global shipping industry, this paper proposes an optimization method for the energy storage capacity of a ship’s hybrid energy system based on a two-layer optimization model, aiming to enhance the energy utilization efficiency and operational stability of the system. A DNN-IPSO optimization framework integrating deep neural networks (DNN) and the improved particle swarm optimization algorithm (IPSO) was constructed, and combined with robust control strategies, it optimized the energy storage capacity configuration problem under complex dynamic conditions. The results show that the proposed method exhibits superior performance in terms of energy utilization efficiency, system dynamic response, and stability. The energy utilization efficiency of the system has been increased to 91.3%, the bus voltage fluctuation has been reduced to 3.98%, the load tracking error has been decreased to 17.6 kW, and the average convergence iteration times have been reduced to 71 times. The 17.6 kW load tracking error accounts for only 1.76% of the rated propulsion power of the 1 MW-level experimental platform, which is approximately 38% lower than that of the GA-PSO method. The experimental results on the real ship show that after using the DNN-IPSO optimization, the unit voyage energy consumption has been reduced to 41.7 kWh/km, the propulsion power stability coefficient has been increased to 0.956, the system transient recovery time has been shortened to 3.2 s, and the power reserve margin has been increased to 18.4%. The proposed method can effectively enhance the energy management capability, dynamic response performance, and operational stability of the ship’s hybrid energy system in the actual operating environment, providing reliable technical support for the engineering application of the integrated energy system of ships. Full article

This paper examines how local firm entry affects air pollution and whether the Air Pollution Prevention and Control Action Plan (APPCAP) changes this relationship. Using a county–month panel for 2010–2020, we match the Chinese Industrial and Commercial Enterprise Registration Database with county-level monthly PM2.5 data to measure new firm entry and its sectoral composition. To address the potential endogeneity of firm entry, we use the opening of high-speed rail as an instrumental variable. The results show that firm entry significantly increases county-level PM2.5 concentrations. This effect is highly heterogeneous across industries, with stronger pollution effects in sectors such as wholesale and retail, manufacturing, and accommodation and catering. We further find that the APPCAP significantly weakens the positive effect of firm entry on air pollution. Additional evidence suggests that the policy improves air quality not only by tightening environmental constraints, but also by shifting firm entry toward relatively cleaner industries. This paper explains the environmental consequences of local economic expansion from the perspective of incremental firm entry and provides new evidence on the joint role of environmental regulation and industrial restructuring in air pollution control. Full article

As the core pillar of international trade, the global shipping industry has seen its carbon and pollutant emissions become a key challenge in global environmental governance. Statistics indicate that ship carbon emissions account for 3% of the world’s total anthropogenic CO₂ emissions, while contributing 20% of global NO_x and 12% of SO₂ emissions, posing a serious threat to coastal ecosystems and public health. In response to the International Maritime Organization (IMO) “Net Zero Framework” and national green shipping policies, the transformation of ship power systems toward low-carbon and zero-carbon operation has become an inevitable trend. This paper systematically reviews the research progress and application status of green energy materials for ships, focusing on the working principles, technical characteristics, and engineering application cases of solar photovoltaic (PV) materials, wind energy utilization technologies, fuel cell materials, and alternative clean energy fuels (e.g., liquefied natural gas (LNG), methanol, and hydrogen energy). It also discusses the integration mode and optimization strategy of multi-energy hybrid power systems. The research findings show that solar photovoltaic technology has achieved large-scale application in coastal ships; hydrogen fuel cells are suitable for long-range ocean navigation scenarios due to their high energy density; LNG and methanol have become the current mainstream alternative fuels, relying on mature infrastructure; and hybrid energy systems can significantly improve power supply reliability and emission reduction efficiency through multi-energy complementarity. Finally, aiming at the existing bottlenecks (e.g., cost, energy storage, and safety) of various technologies, future development directions are proposed. This study provides a reference for the technological breakthrough and engineering practice of green energy power systems for ships and contributes to the realization of the “carbon neutrality” goal in the global shipping industry. Full article

Continuous discharges from diverse industrial activities have severely degraded the water quality of the Lerma River, turning it into a major environmental, social, and public health concern. Conventional wastewater treatment processes are often insufficient for eliminating persistent and refractory organic pollutants; therefore, the implementation of advanced oxidation processes (AOPs) is increasingly required to restore water quality. In this context, the present study systematically evaluated the individual and combined effects of ozonation and electrochemical oxidation using boron-doped diamond (BDD) electrodes for the treatment of contaminated river water. Ozonation alone achieved an 89% reduction in turbidity and a 19% decrease in total organic carbon (TOC), while electrochemical oxidation reduced turbidity by 82% and TOC by 57%. Remarkably, the simultaneous application of both treatments resulted in a 98% reduction in turbidity and an 80% decrease in TOC, clearly demonstrating a strong synergistic effect. Regarding true color at 436 nm, associated with yellow chromophore compounds, removal efficiencies of 98.9%, 94.7%, and 67.3% were obtained for the combined process, electrochemical oxidation, and ozonation, respectively. Phytotoxicity tests with Lactuca sativa seeds showed no statistically significant difference in toxicity in water treated with the O₃–EO System compared to raw water. These results highlight, for the first time under real river water conditions, the superior performance of the integrated O₃–EO system as an effective strategy for the intensified degradation and partial mineralization of persistent organic contaminants, thereby underscoring its strong potential for advanced remediation of heavily polluted surface waters. Full article

Persistent organic pollutants such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) remain a public health concern due to their persistence, bioaccumulation, and potential health effects. Human breast milk is an important biomonitoring matrix for assessing maternal and infant exposure to lipophilic contaminants. This pilot study aimed to determine concentrations of PCDD/Fs, dioxin-like PCBs (dl-PCBs), and non-dioxin-like PCBs (ndl-PCBs) in breast milk samples collected from five lactating women residing in the Greater Poland Province and to explore potential determinants of exposure. Following participant recruitment, sample collection, and questionnaire-based assessment performed by the authors, breast milk samples were analyzed at the accredited Laboratory of Trace Analysis (Cracow University of Technology, Poland) using isotope dilution gas chromatography coupled with tandem mass spectrometry. Toxic equivalency values (TEQ) were calculated using World Health Organization 2005 toxic equivalency factors (WHO-TEFs). WHO-PCDD/F-TEQ ranged from 0.096 to 0.22 pg/g fresh weight. Median lipid-normalized WHO-PCDD/F-TEQ and total WHO-PCDD/F-PCB-TEQ concentrations were 3.5 and 4.7 pg/g lipid, respectively, remaining below the European Food Safety Authority (EFSA) reference level of 5.9 pg/g lipid; only one sample exceeded this threshold (6.2 pg/g lipid). Lipid-normalized WHO-PCB-TEQ correlated positively with maternal age (ρ = 0.949, p = 0.0389). The observed values were within the lower range reported in recent European studies. The congener patterns suggest a combination of chronic exposure to combustion by-products and long-term bioaccumulation of historical industrial pollutants. Although limited by the small sample size, this exploratory study provides preliminary regional biomonitoring data supporting future environmental exposure research. Full article

Fine particulate matter (PM_2.5) composition, rather than mass alone, plays a critical role in determining toxicity and health impact. This study examined short-term associations between daily PM_2.5 constituents—black carbon (BC), nitrate (NO₃⁻), ammonium (NH₄⁺), and trace elements—and cardiopulmonary hospital admissions in Makkah, Saudi Arabia. Twelve months of constituent data from the Alharam monitoring site were linked to Herra hospital admissions for cardiovascular (CVD) and pulmonary diseases, stratified by visit type, age, and sex. Negative-binomial generalized linear models estimated adjusted relative risks (aRRs) per interquartile range increase in each constituent, controlling for meteorology, seasonality, and temporal trends. Mean PM_2.5 was 113.6 µg/m³; BC, sulfur, NO₃⁻, and NH₄⁺ dominated the fine fraction. Crustal elements were strongly intercorrelated (r > 0.9), while BC, lead (Pb), and nickel (Ni) showed moderate correlations (r ≈ 0.4–0.6), suggesting shared anthropogenic origins. BC increased CVD emergency/outpatient visits by 18% (aRR = 1.18; 95% CI: 1.08–1.29) and inpatient admissions by 25% (aRR = 1.25; 95% CI: 1.07–1.46). Ni and sulfur were also significant predictors; crustal elements were not. Multi-pollutant models confirmed BC and Pb as independent predictors (aRR = 1.19; 95% CI: 1.02–1.38). Effects were strongest among older adults aged 45–65 at lag 0–2 days. These findings highlight the need for emission controls targeting traffic and industrial combustion sources. Full article

p-Methoxy-m-nitrobenzoic acid (MNBA) serves as a valuable chemical intermediate across numerous domains. Nevertheless, the synthesis of MNBA through non-catalytic oxidation processes invariably results in the production of environmentally polluting substances. In this study, we report an environmentally benign catalytic oxidation system for the synthesis of MNBA using water as a solvent. Based on the two-step TEMPO/KBr/NaOCl/NaClO₂ system, which achieved a 91.4% yield at 70 °C, we have devised a simplified one-step procedure employing the TEMPO/KBr/NaClO₂ system. This less energy-intensive input method yields 90.1% MNBA at 60 °C. Systematic optimization has revealed that temperature, time, and oxidant quantity are critical parameters. Furthermore, acidic conditions have been found to reduce yields due to the decomposition of NaClO₂. The aqueous-phase approach completely avoids organic solvents and facilitates product isolation. A synergistic catalytic mechanism involving N-oxoammonium intermediates is proposed. This work establishes a sustainable strategy for preparing multifunctional aromatic carboxylic acids, addressing key challenges in both ecological impact and industrial scalability for fine chemical production. Full article

Heavy metal(oid) pollution in tea plantation has become a global concern threatening tea safety, with food safety serving as the cornerstone of the tea industry. In this study, the distribution and migration patterns of seven heavy metal(oid)s in soil-tea systems developed from three parent materials were investigated, in the geologically complex but minimally human disturbed Dabie Mountains. Results showed that although the heavy metal(oid) concentrations in tea at all sampling points meets the food safety standards of China and the European Union, significant differences existed in the bioaccumulation potential of the elements. Hg and Cd showed the highest bioconcentration factors (mean values of 0.45 and 0.33, respectively), while As, Cr, and Pb transfer were inhibited. Geological type significantly influenced the heavy metal(oid) distributions. Random forest models revealed metal-specific transfer mechanisms, with P-related variables (e.g., soil total P, available P, and microbial biomass P) and microbial C-N acquisition enzyme activities serving as key regulatory factors. This study confirms that parent materials indirectly potentially influence heavy metal(oid) bioavailability by shaping soil development and microbial functions, providing scientific basis for geology-informed food safety risk assessment in tea plantations. Full article

Poorly soluble hydrophobic organic pollutants, such as indole and diethyl phthalate (DEP), are difficult to remove efficiently from complex industrial wastewater due to low solubility and competitive adsorption. In this study, low-rank coal-based activated cokes derived from Wanli long-flame coal and Zhaotong lignite were modified through a combined process of acid-washing pretreatment and trimethylchlorosilane (TMCS) grafting. The acid-washing step effectively removed ash and unblocked pores, increasing the specific surface area and pore volume of the optimized Zhaotong lignite-based sample by 43.7% and 53.3%, respectively. Subsequent TMCS grafting successfully introduced hydrophobic methyl groups onto the surface, significantly enhancing hydrophobicity. The water contact angles of the composite materials (acid-washed plus TMCS-grafted) increased to 127.3° and 139.7°, compared to 117.8° and 112.6° for the original samples. The modified adsorbent derived from Zhaotong lignite exhibited high adsorption capacities, reaching 139.47 mg·g⁻¹ for indole and 120.19 mg·g⁻¹ for DEP in single-component systems, representing an increase of 20.1% for indole and 28.7% for DEP compared to the unmodified adsorbent. More importantly, in a competitive system containing phenol at PH = 10, the materials demonstrated superior selectivity towards the target hydrophobic pollutants. The phenol removal rate was 65.97%, and the removal rates for indole and DEP increased sharply to 98.17% and 92.17%, respectively. This work provides a feasible strategy for the advanced treatment of complex organic wastewater using coal-based adsorbents, achieving a dual enhancement in both adsorption capacity and selectivity. Full article

Conventional wastewater treatment systems cannot effectively eliminate micropollutants such as contaminants of emerging concern (CECs). These compounds, even at trace levels, are persistent or pseudo-persistent, bioaccumulative, and potentially harmful to ecosystems and human health. Advanced oxidation processes (AOPs), based on the in situ generation of highly reactive oxygen species, have emerged as promising solutions. Peroxyacetic acid (PAA) has gained attention due to its strong oxidizing capacity, broad antimicrobial activity, environmentally benign by-products, and compatibility with different activation methods. This review provides an updated and integrated synthesis of recent advances in PAA-based AOPs for the degradation of major CEC groups, including pharmaceuticals, personal care products, pesticides, and industrial chemicals, as well as for the oxidative modification of microplastics (MPs). The review discusses several strategies for PAA activation and critically discusses removal efficiency, underlying mechanisms, and current limitations, emphasizing the gap between pollutant transformation and complete mineralization. Furthermore, the article highlights a key research need, which is the assessment of the toxicity of transformation products and their validation under realistic conditions. Overall, this review provides insight into the potential and challenges of PAA-based AOPs for sustainable water treatment. Full article