Investigations into the characteristics and phase-partitioning behavior of alkylated polycyclic aromatic hydrocarbons (alkyl-PAHs) during coal combustion process remain notably limited. This study aims to analyze the source characteristics, distribution patterns, and partitioning mechanisms of parent and alkyl-PAHs in gas and particle phase emissions from coal combustion. The results show that 30.77 %-49.37 % of parent PAHs from coking, gas, lean and fat coal combustion emissions are distributed in gas phases, while it accounts for 78.59 % in lignite coal combustion emission. In terms of alkyl-PAHs, 79.05 %-89.45 % of coking, gas and lean coal combustion emissions are presented in particle phases, and 62.66 %-69.32 % of lignite and fat coal combustion emissions are presented in gas phases. Moreover, the PAH p-values from coal combustion emissions are in the range of-1.00 to-0.68, and the alkylated ones range from-0.80 to-0.54. Interestingly, alkylated phenanthrenes maintain a high degree of uniformity in the distribution patterns of combustion emissions, and their bell-shape distribution pattern performs to be a potential indicator of coal combustion. Furthermore, by employing partitioning models, it can be proven that absorption and adsorption are governing PAH partitioning mechanisms, and alkyl-PAHs can reach equilibrium more rapidly than parent PAHs. These findings offer detailed data into source analysis and the fate of alkyl-PAHs from coal combustion, which is expected to be helpful for environmental behavior investigation and better pollution control of coal combustion.

The 83rd session of the IMO Maritime Environment Protection Committee (MEPC 83) approved a global pricing mechanism for the shipping industry, with formal adoption scheduled for October 2025. Proposed mechanisms include the International Maritime Sustainable Fuels and Fund (IMSF&F) and a combined approach integrating GHG Fuel Standards with Universal GHG Contributions (GFS&UGC). This study developed a model based on the marginal abatement cost curve (MACC) methodology to assess the cost-effectiveness of alternative fuels under both mechanisms. Sensitivity analyses evaluated the impacts of fuel prices, carbon prices, and the GHG Fuel Intensity (GFI) indicator on MAC. Results indicate that implementing the GFS&UGC mechanism yields higher net present values (NPVs) and lower MACs compared to IMSF&F. Introducing universal GHG contributions promotes a comparatively fairer transition to sustainable shipping fuels. Investments in zero- or near-zero-fueled (ZNZ) ships are unlikely to be recouped by 2050 unless carbon prices rise sufficiently to boost revenues. Bio-Methanol and bio-diesel emerged as the most cost-competitive ZNZ options in the long term, while e-Methanol’s poor competitiveness stems from its extremely high price. Both pooling costs and universal GHG levies significantly reduce LNG’s economic viability over the study period. MACs demonstrated greater sensitivity to fuel prices (Pfuel) than to carbon prices (Pcarbon) or GFI within this study’s parameterization scope, particularly under GFS&UGC. Ratios of Pcarbon%/Pfuel% in equivalent sensitivity scenarios were quantified to determine relative price importance. This work provides insights into fuel selection for shipping companies and supports policymakers in designing effective GHG pricing mechanisms.

This study conducted a comparative investigation of polycyclic aromatic hydrocarbons (PAHs) contamination characteristics across several functional zones in Haizhou Bay, a historic marine aquaculture area in China. The results revealed spatial differences in PAH concentrations, with the estuarine zone exhibiting the highest contamination levels, followed by the artificial reef, natural, aquaculture, and comprehensive effects zones. Notably, the PAH composition in Haizhou Bay has undergone a marked transition in recent years, shifting from predominantly 4-6 ring compounds to 2-3 ring species. This compositional change likely reflects regional energy structure transitions. Source apportionment demonstrated zonal variations in PAH origins: the estuarine zone was predominantly influenced by transportation-related emissions, as evidenced by elevated naphthalene concentrations, while the artificial reef zone sediments showed strong signatures of coal and biomass combustion, particularly through enhanced phenanthrene levels. Other zones presented characteristic petrogenic PAH profiles. The ecological risk of sedimentary PAHs in Haizhou Bay was deemed to be minimal based on the mean effects range-median quotient (M-ERM-Q).The overall findings underscore that the spatial heterogeneity of pollution sources can directly determine the distribution pattern of sedimentary PAHs in different functional zones. These efforts also attempt to provide a scientific basis for implementing zoning-based management strategies to mitigate PAH-induced ecological risks in similar marine aquaculture areas.

This study aims to investigate the interactions between marine oil snow (MOS) formation and soot particles derived from two distinct oils: condensate and heavy oil. Experimental findings demonstrate that the properties of oil droplets and soot particles play a key role in MOS formation. Peak MOS formation is observed within the initial days for condensate, while for heavy oil, peak formation occurs at a later stage. Furthermore, the addition of oils and soot particles influences the final concentrations of polycyclic aromatic hydrocarbons (PAHs) in MOS. Remarkably, the ranking order of PAHs with different rings in various MOS samples remains consistent: 4- > 3> 5- > 2- > 6-ring. Specific diagnostic ratios such as Phe/Ant, Ant/(Ant + Phe), BaA/(Chr + BaA), and LMW/ HMW effectively differentiate petrogenic and pyrogenic sources of PAHs in MOS. And stable ratios like Flu/(Pyr + Flu), InP/(InP + BghiP), and BaF/BkF are identified for source analysis of soot MOS.

This study aims to solve the discharge of printing and dyeing reverse osmosis concentrate (PDROC) from a local printing and dyeing factory in Hangzhou, China. Electrochemical technique was used to treat the organic content of the concentrated wastewater. At the same time, the concentration levels of the target chemical species were double-checked using liquid–liquid extraction-gas chromatography–mass spectrometry and the UV–Vis spectroscopy. The findings revealed that the contaminants in the wastewater were primarily consisted of semi-volatile organic compounds such as long-chain alkanes, aromatics, and phthalates, with the concentration of dibutyl phthalate (DBP) being 64.4 µg/L. Decent removal efficiencies of chemical oxygen demand (COD) and DBP were observed after 3-h electro-degradation, which reached 73.6

To understand the influences of emulsified fuel on ship exhaust emissions more comprehensively, the emissions of particulate matter (PM), nitrated, oxygenated and parent polycyclic aromatic hydrocarbons (PAHs) were studied on a ship main engine burning emulsified heavy fuel oil (EHFO) and heavy fuel oil (HFO) as a reference. The results demonstrate that EHFO (emulsified heavy fuel oil) exhibits notable abilities to significantly reduce emissions of particulate matter (PM) and low molecular weight PAHs (polycyclic aromatic hydrocarbons) in the gas phase, particularly showcasing maximum reductions of 13.99% and 40.5%, respectively. Nevertheless, burning EHFO could increase the emission of high molecular weight PAHs in fine particles and pose a consequent higher carcinogenic risk for individual particles. The total average (gaseous plus particulate) ΣBEQ of EHFO exhausts (41.5 μg/m3) was generally higher than that of HFO exhausts (18.7 μg/m3). Additionally, the combustion of EHFO (extra-heavy fuel oil) can significantly alter the emission quantity, composition, and particle-size distribution of PAH derivatives. These changes may be linked to molecular structures, such as zigzag configurations in C=O bonds. Our findings may favor the comprehensive environmental assessments on the onboard application of EHFO.

In this work, a constructed five-compartment electrodeionization (EDI) device was used to treat simulated wastewater with ammonium and phosphate ions. The voltage and influent concentration in the EDI system were examined. Meanwhile, the ion migration characteristics in the EDI were studied. Results showed that at optimal conditions, operating at 15 V, with an ammonia nitrogen concentration of 1500 mg/L, and a phosphate concentration of 300 mg/L, the removal rates of ammonia nitrogen and phosphate were 98.50 % and 73.85 %, respectively. The energy consumption of ammonia and phosphorus was 1.347 kWh/mol and 43.629 kWh/mol. The ion migration characteristic experiments revealed that adsorption and desorption rates of the resin do not impose limitations on ion migration in EDI; the ion migration in EDI device is mainly through the resin phase and the rate of ion migration is intricately influenced by the concentration of nutrient ions present on the resin.

This study aims to predict the economic transition pathway for alternative fuels in accordance with the 2023 IMO GHG Strategy goals. The assessment considers the impact of alternative fuel transition on fuel costs (∆COSTFuel,t), carbon emission costs (∆COSTCO2 eq,t), and ship new/retrofit costs (∆COSTship). The parameters and boundary conditions were set based on the current status and trends in the international shipping industry, as determined from previous research, to predict the economic transition pathway for alternative fuels. The results show that in 2050, with a standardized economic efficiency of 130%, profit will reach its maximum value, approximately −54,000 million USD. The study standardized fuel ΔCOSTj, normalized, and ΔNPV%j, normalized as a basis for adjusting penetration rates. At this time, considering fuel costs and NPV%, the composition of alternative fuels is as follows: bio-LNG, bio-Methanol, e-LNG, e-Methanol, e-Ammonia, BD, and Fossil-LNG, with shares of 18.56%, 4.00%, 25.64%, 6.00%, 10.00%, 28.00%, and 0%, respectively. Compared to conventional marine fuel HFO, the increase ranges from 23.54% to 69.50% in the 2030s, 0.52% to 0.55% in the 2040s, and decreases by 6.88%–14.69% in 2050. Using more LNG and BD in the 2040s and 2050 is an alternative way to achieve a better economic fuel transition. Moreover, the economic penetration rate combination set in this study can achieve sufficiently small ∆COSTT,t and sufficiently large NPVΔt under specific assumptions and boundary conditions, rather than an absolute minimum ∆COSTT,t or the absolute maximum NPVΔt. The results revealed that no single alternative fuel has a comprehensive advantage in reducing carbon intensity and economic performance at all times. Given the uncertainties in the supply chain, cost-effectiveness, and infrastructure for Methanol and Ammonia, LNG and BD play a crucial role in the transition of international shipping fuels. Our work provides a fundamental and comprehensive prediction of fuel transition based on the current status and trends in the international shipping industry.

The Huanghe Estuary, which is characterized by dynamic hydrological and ecological processes, is highly susceptible to marine oil spills due to dense maritime traffic and extensive industrial activities. This study evaluated the vulnerability of estuarine wetlands in the Huanghe Estuary to oil spill stress using the Pressure-Situation-Sensitivity-Recovery (PSSR) framework. By employing the Geographic Information System (GIS) and the Analytic Hierarchy Process (AHP), this study categorized the vulnerability index (0–1) into five classes: Very Low (0–0.098), Low (0.098–0.125), Medium (0.125-0.192), High (0.192–0.224), and Very High (0.224–1). The results indicate that the ships indicator has the highest weight, followed by oil rigs. In contrast, the number of chemical splash-proof suits and tugboats have the lowest weights. Wetland vulnerability under oil spill stress exhibited significant spatial variation, with higher vulnerability observed in areas closer to the coastline, such as the eastern part of Kenli County, the northern part of Wudi County, and the northern part of Hekou District. This study underscores the need for targeted measures and enhanced monitoring to mitigate the risks of large oil spills and protect the ecological integrity of the Huanghe Estuary. The findings presented herein provide critical information that will help policymakers and environmental managers implement effective conservation strategies and risk mitigation efforts in this ecologically sensitive and economically important region.

The 80th session of the IMO Maritime Environment Protection Committee (MEPC 80) adopted the 2023 IMO Strategy on the Reduction of GHG Emissions from Ships (2023 IMO GHG Strategy), with enhanced targets to tackle harmful emissions. This study strives to provide an exact interpretation of the target of the 2023 IMO GHG Strategy and reveal the technical requirements therein. Decarbonization targets were expressed in IMO GHG emission scenarios for specifications. Model calculations and parameterizations were in line with IMO GHG reduction principles and decarbonizing practices in the shipping sector to avoid the prejudicial tendency of alternative fuels and the overestimated integral efficiency of short-term measures in existing predictions. IMO DCS data were used for the first time to gain reliable practical efficiencies of newly adopted regulations and further reduce the model uncertainty. The results demonstrated that the decarbonization goals for emission intensity were actually 51.5–62.5% in the IMO GHG reduction scenarios, which was much higher than the IMO recommended value of 40% as the target. Combined with the continuous applications of short-term measures, onshore power and regulations were required to contribute their maximum potential no later than the year 2030. Even so, considerable penetration (15.0–26.0%) of alternative fuels will be required by 2030 to achieve the decarbonization goals in the 90% and 130% scenarios, respectively, both far beyond the expected value in the 2023 IMO GHG Strategy (i.e., 5–10%). Until 2050, decarbonization from alternative fuels is required to achieve ~95%. Sustainable biodiesel and LNG are the necessary choices in all time periods, while the roles of e-methanol and e-ammonia deserve to be considered in the long term. Our findings highlight the intense technical requirements behind the 2023 IMO GHG Strategy and provide a pathway option for a fair and impartial transition to zero GHG emissions in the shipping sector, which might be meaningful to policymakers.

To comprehensively clarify the pollution characteristics of persistent toxic substances, the Soil and Air Monitoring Program Phase III (SAMP-III) was conducted in 2019 in China. In total, 154 surface soil samples were collected across China, and 30 unsubstituted polycyclic aromatic hydrocarbons (U-PAHs) and 49 methylated PAHs (Me-PAHs) were analyzed in this study. The mean concentrations of total U-PAHs and Me-PAHs were 540 ± 778 and 82.0 ± 132 ng/g dw, respectively. Northeastern China and Eastern China are the two regions of concern with high PAH and BaP equivalency levels. Compared with SAMP-I (2005) and SAMP-II (2012), an obvious upward temporal trend followed by a downward trend of PAH levels was observed in the past 14 years for the first time. The mean concentrations of 16 U-PAHs were 377 ± 716, 780 ± 1010, and 419 ± 611 ng/g dw in surface soil across China for the three phases, respectively. Considering rapid economic growth and energy consumption, an increasing trend from 2005 to 2012 was expected. From 2012 to 2019, the PAH levels in soils across China decreased by 50 %, which was consistent with the decline in PAH emissions. The period of reduction of PAHs in surface soil coincided with the implementation of Air and Soil Pollution Control Actions in China after 2013 and 2016, respectively. Along with the pollution control actions in China, the pollution control of PAHs and the increase in soil quality can be expected in the near future.

The documents concerning the calculation of conversion coefficients for marine fuels are reviewed to see the rationality of the conversion coefficients given by IMO.The method of calculating the coefficients is analyzed.Inconsistency in given atomic weight approximations for carbon,hydrogen and oxygen is found.Besides,the fundamental data source is not up to date.These problems are degrading the accuracy of carbon emission calculations.The corrections for the conversion coefficients are proposed.The conversion coefficients for ethane and bio-gasoline/biodiesel are calculated.A proposal on timely revising the conversion coefficients is prepared.Prudent treatment is suggested in using the conversion coefficients given by IMO to evaluating domestic emissions.

为解决目前船舶废气中SO2排放不达标的问题,利用聚四氟乙烯(polytetrafluoroethylene,PTFE)中空纤维膜搭建船舶废气膜法海水脱硫系统,包括废气冷却除尘预处理单元和PTFE膜法脱硫单元.在船舶发动机功率为14、27、41 kW等3种工况下,研究其对废气中SO2的脱除效果.结果表明:干净的冷却水能吸收废气中部分SO2,且系统在任一工况下运行30 min后冷却水对SO2的吸收达到饱和;当冷却水水温控制在15℃,喷淋量大于4 m3/h时,喷淋后的废气温度均可控制在40℃以下;只要控制模拟海水的pH在7.0以上,PTFE膜法脱硫单元对废气中SO2的脱除率均可达到100％.

Contamination information are desired to fill the gap in the understanding of environmental effects by parent-, nitrated- and oxygenated PAHs (p, n, o-PAHs) from ship stacks. In this study, the organic films on ferries along Huangpu River, one of the busiest inland rivers around the world, were measured seasonally and the compartmental concentrations were rebuilt through a fugacity model to this end. Results revealed that considerable levels of p, n, o-PAHs could be detected in the ferry films. Few seasonal or spatial variations were observed, which indicated a dominant emitter existing in the environments along the river. The compositions of p, n, o-PAHs could be associated with internal combustion engine emissions, however, the composition was different to contamination patterns of on-road traffics. Accordingly, the ship-stack exhausts were suggested to be the primary contributor of p, n, o-PAHs in ferry films. The results of PCA and PMF showed that InP and BghiP could represent the ship-stack PAHs along Huangpu River. Our study highlights a dramatic contribution of ship activities to the contaminations along Huangpu River and provides supports for the usage of organic films on ships as a representative 'sampler' of ship-stack emissions.

为减少国际海运温室气体排放,国际海事组织海洋环境保护委员会于2023年修订了减排策略.通过对《2023年国际海事组织船舶温室气体减排战略》中关于排放状况预测、目标水平、实施原则、指导措施和时间节点等要点的解读,阐释"措施矩阵"的中期措施中关于成员国影响评估框架的技术和经济要素含义以及可能的使用方式,推论《2023年国际海事组织船舶温室气体减排战略》在实施过程中可能面临的障碍,以及可能获得支持的方式.

Interfacial solar steam generation has been proposed as an eco-friendly way for water desalination. However, the current interfacial evaporator still suffers from a complex process, high preparation cost, and poor stability. Here, by means of picosecond laser treatment of the aluminium surface, we developed a superhydrophilic, anti-gravity wicking, and efficient solar desalination evaporator. The picosecond laser treated aluminium (PLAL) surface has an open capillary structure, which contributes to the rapid transfer and evaporation of seawater. Moreover, larger size water clusters are formed on the surface, hence lowering its enthalpy of water evaporation dramatically to 541.25 +/- 0.07 kJ/kg, which can effectively increase the evaporation rate to 1.24 kg.m(-2).h(-1) under one sun irradiation (1 Kw.m(-2)) even with only 67% energy efficiency, and is 0.3 kg.m(-2).h(-1) higher than that treated by high-cost femtosecond laser. Even under weaker natural sunlight, the evaporation rate remains 0.7-0.9 kg.m(-2).h(-1). Additional experiments were carried out at low laser power (30%) to evaluate the effect of PLAL surface structure on anti-gravity wicking. Additionally, during 25-day continuous desalination, the evaporation performance of PLAL surface remains stable, in contrast to that placed in ambient air, which changes to hydrophobic 20 days after laser treatment. Furthermore, low temperature annealing can restore the PLAL surface, which has been converted to hydrophobic, to superhydrophilic. The reason for transition may attribute to the increase in the carbon content of the surface causing an increase in the relative content of the C-C bond of the surface. The PLAL surface fabricated here is easy to fabricate and scale-up and exhibits the potential to efficient desalinate seawater and purify wastewater, etc.

In this paper, internal anodization of porous Ti was performed to fabricate immobilized TiO2 nanotubes with a high specific surface area. The results showed that complete internal anodization of porous Ti was achieved, self-ordered and open-topped TiO2 nanotube arrays were successfully formed within the whole region of porous Ti by applying high anodizing voltage, long oxidation time and enhancing mass transfer. The BET specific surface area of anodized porous Ti reached 16.96 m2/g, which was almost 60 times that before anodic oxidation. Moreover, due to the potential drop and mass transfer, the nanotube growth was larger at the front surface than the back surface, and decreased as they were inward further away from the surface. The anodized porous Ti with a high specific surface area not only benefits the designing of highly active TiO2-based photocatalysts, but also shows great potential for applications in adsorption and electrocatalysis etc.

A polytetrafluoroethylene (PTFE) doped PbO2 anode with a highly hydrophobicity was fabricated by electrodeposition method. In this process, vertically aligned TiO2 nanotubes (TiO2NTs) are formed by the anodic oxidation of Ti plates as an intermediate layer for PbO2 electrodeposition. The characterization of the electrodes indicated that PTFE was successfully introduced to the electrode surface, the TiO2NTs were completely covered with beta-PbO2 particles and gave it a large surface area, which also limited the growth of its crystal particles. Compared with the conventional Ti/PbO2 and Ti/TiO2NTs/PbO2 electrode, the Ti/TiO2NTs/PbO2-PTFE electrode has enhanced surface hydrophobicity, higher oxygen evolution potential, lower electrochemical impedance, with more active sites, and generate more hydroxyl radicals (center dot OH), which were enhanced by the addition of PTFE nanoparticles. The electrocatalytic performance of the three electrodes were investigated using dibutyl phthalate (DBP) as the model pollutant. The efficiency of the DBP removal of the three electrodes was in the order: Ti/TiO2NTs/PbO2-PTFE > Ti/TiO2NTs/PbO2 > Ti/PbO2. The degradation process followed the pseudo first-order kinetic model well, with rate constants of 0.1326, 0.1266, and 0.1041 h(-1) for the three electrodes, respectively. The lowest energy consumption (6.1 kWh g(-1)) was obtained after 8 h of DBP treatment using Ti/TiO2NTs/PbO2-PTFE compared to Ti/TiO2NTs/PbO2 (6.7 kWh g(-1)) and Ti/PbO2 (7.4 kWh g(-1)) electrodes. Moreover, the effects of current density, initial pH and electrolyte concentration were investigated. Finally, the products of the DBP degradation process were verified based on gas chromatography-mass spectrometry analysis, and possible degradation pathways were described.

Onboard commercialization of the emulsified fuel has been considered in accordance with the IMO’s (International Maritime Organization) increasing focus on controlling NOx emission. To understand the influences on ship exhaust emissions more comprehensively, the emissions of particulate matter (PM), nitrated-, oxygenated- and parent polycyclic aromatic hydrocarbons (PAHs) were studied on a ship main engine burning emulsified heavy fuel oil (EHFO), and HFO as reference. The results indicated that EHFO exhibited good abilities to reduce the emissions of PM and low molecular weight PAHs in gas phase, especially at low operation modes. Nevertheless, burning EHFO could increase the emission of high molecular weight PAHs in fine particles and pose a consequent higher carcinogenic risk for individual particle. In addition, burning EHFO could also alter the emission amount, composition and particle-size distribution of the PAH derivatives dramatically, which could be associated with the molecule structures such as the zigzag cite of C=O bond. Our findings may favor the comprehensive environmental assessments on onboard application of EHFO.

This study characterized the parent and alkylated polycyclic aromatic hydrocarbons (PAHs) in gaseous and particulate emissions from the in situ burning (ISB) of oils. The experimental results indicate that the burning of the heavy oil produced the most PAH emissions because of its longest burning time. In addition, the parent PAHs mainly exist in the particulate phase, while alkylated PAHs mostly accumulate in the gaseous phase. In particular, the diagnostic-ratios of PAHs with great stability in both gaseous and particulate emissions from ISB are identified by comparing the laboratory and field data. The presences of bell-, slope- and V-shaped distribution patterns of alkylated PAHs in the emissions precisely indicate their sources to be petrogenic and pyrogenic processes occurring during ISB. The formation of 2-methylanthracene during ISB is confirmed. The overall findings are expected to provide a prospective protocol to characterize PAH pollution from ISB emissions in case of oil spills.