Emission Standards Research Articles

Features of Carbon Regulation in the Republic of Belarus and the Russian Federation: Comparative Analysis and Trends

The article reviews international acts in the field of combating climate change (United Nations Framework Convention on Climate Change, Kyoto Protocol and Paris Agreement), identifies the main trends in the field of carbon regulation: emissions quoting; implementation of climate projects; introduction of greenhouse gas reporting and expansion of the legislative framework. A comparative analysis of the national legislation in force in the Republic of Belarus and the Russian Federation is carried out, its conditional classification is considered with the allocation of carbon regulation instruments being applied, viz. the market ones, the restrictive ones, the supporting ones and the auxiliary ones. The regulation of greenhouse gas emissions should include a wide range of activities and cannot be reduced solely to restrictive instruments. Market instruments include the national emissions trading system, international voluntary markets and instruments of international cooperation, while restrictive instruments include the introduction of carbon taxes, quotas, and mandatory carbon reporting. Among the examples of supporting instruments subsidies, targeted financing and tax preferences, as well as information policy may be noted. Auxiliary instruments include methodologies for quantitative assessment of greenhouse gas emissions and uptake, carbon reporting standards and tools for verification of reporting on greenhouse gas emissions, legislated possibility of implementing climate projects. The normative national regulation regarding the accounting of greenhouse gas emissions is considered, the categories of emission sources and greenhouse gases whose emissions are subject to accounting are identified. It is important to note that the legislation on greenhouse gases in the Republic of Belarus and the Russian Federation, as well as around the world, has not been finalized and is in the process of formation.

Assessing the Impact of CO2 Emissions from Transport and Power on Health and Environment in Duhok, Kurdistan Region, Iraq

This study investigates the carbon dioxide (CO2) emissions generated by transportation and power generation in Duhok Governorate, Kurdistan Region of Iraq. The research highlights the alarming levels of CO2 emissions resulting from the region's 270,315 vehicles and 1,814 private electric power generators, which consume approximately 1,500,000 liters of gasoline and 650,000 liters of diesel daily. These activities contribute to a total daily CO2 emission of 1,741,188 kg, amounting to over 626,827,680 kg annually. The findings reveal the significant environmental and public health threats posed by these emissions, emphasizing the urgent need for targeted mitigation strategies. Comparisons with other urban regions such as Cairo, Tehran, New Delhi, Lagos, and Nairobi reveal a similar pattern of high vehicular and generator-induced CO2 emissions, underscoring the global nature of this environmental challenge. The study underscores the importance of addressing CO2 emissions through improved regulations, modernized infrastructure, and sustainable energy practices to protect both the environment and public health.

Impacts of On‐Road Vehicular Emissions on U.S. Air Quality: A Comparison of Two Mobile Emission Models (MOVES and FIVE)

AbstractOn‐road vehicles are significant contributors to air pollution globally, particularly to nitrogen oxides (NOx) and ozone (O3). Quantifying their contribution to air quality is crucial to understanding the trends of vehicle emissions as low‐ and “zero” emission vehicles join the fleet. Modeling on‐road emissions is complex due to various factors like fleet activities, traffic patterns, and meteorological conditions. We compare on‐road emissions from two mobile models: the National Oceanic and Atmospheric Administration Fuel‐based Inventory of Vehicle Emission (FIVE) and the US Environmental Protection Agency Motor Vehicle Emission Simulator (MOVES), finding they contribute 4%–33% to volatile organic compounds (VOCs), NOx, and fine particulate matter (PM2.5) in the contiguous United States (CONUS). Using a regional chemical transport model, we assess air quality effects under different emission scenarios. Both emission data sets yield satisfactory performance, with MOVES showing lower biases in ozone (O3) and PM2.5 over CONUS, while FIVE performs better at city scales due to higher urban NOx emissions. In January, on‐road emissions increased surface O3 over western and southern US by up to 9.1%–13.1% but decreased by 2.5% over the northeastern US, while PM2.5 predictions vary across the US (−85% to 24%). In July, on‐road emissions elevate O3 and PM2.5 concentrations by 15%–20% across CONUS, except in some west coast cities. They also greatly contribute to nitrogen dioxide (NO2) by more than 80% near roads and in urban areas. This study highlights the significant impact of on‐road emissions on urban air quality and provides insights for improving air quality forecasting and management.

Modeling cigarette smoking exposure in subsets of the population

Modeling cigarette smoking exposure in subsets of the population Understanding and acknowledging various factors that impact cigarette smoking and exposure is critical when creating public health interventions to curb tobacco use. Here, Theodore R. Holford from Yale University discusses the impact of different approaches to tobacco control. The harmful effects of cigarette smoking have been widely recognized for more than 50 years (1), and the huge toll that it has taken in shortening lives has led to the recognition of an urgent need to reduce associated exposure. Because cigarette smoking is an addictive behavior, it has been a public health challenge to reduce the level of exposure in the population, even though alternative approaches have been used. These approaches include the introduction of taxes that increase cost to users, changing the legal age at which cigarettes can be purchased, introducing clean air laws that limit locations where individuals are allowed to smoke, and establishing resources that will assist those who wish to quit smoking. These efforts can be undertaken on a national level, but more often, such efforts are implemented at different times and in different ways in different regions. In the US, these laws are more commonly introduced by a state, county, or city. (2) This introduces geographic disparities in cigarette smoking exposure, and it is important to understand these differences when planning approaches to protect public health.

Two different approaches for source apportionment of ambient black carbon in highly polluted environments

The aethalometer model (AM) is widely used for source apportionment (SA) of black carbon (BC) in regions with mixed BC sources despite being initially developed for a relatively simplistic and low-pollution environments. The present study interrogates the applicability of AM in highly polluted metropolitan environments by comparing its results with the more nuanced Positive Matrix Factorization (PMF) model. The measurements were conducted in Delhi during the winter and summer season. PMF apportions the BC into diverse sources by taking help from complementary trace elemental measurements, thereby acknowledging the complex pollution landscape of the Delhi region. The AM estimates BCbb (BC from biomass burning) and BCff (BC from fossil fuel combustion) contributions as 48.3% and 51.7% during the winter and 16.6% and 83.4% during the summer, respectively.In contrast, the PMF model-derived biomass burning factor is the dominant source of BC during both winter and summer seasons, contributing 53.9% and 44% of the total BC, respectively. The decrease in light absorption at UV wavelengths of biomass-burning aerosols owing to escalated ambient aging is posited to be the reason for BCbb underprediction by the AM model during summers. Furthermore, while the AM model identifies fossil fuel combustion as the only other BC source apart from biomass burning, the PMF model apportions BC to five additional sources during winter, including vehicle emissions (22.9%), Pb-rich factor (10%), power plant (5.7%), waste incineration (4%) and industrial emission (3.6%). The contribution of these BC sources during summer is vehicular emission (16.5%), power plant (14.5%), waste incineration (11.5%), Pb-rich factor (9.5%), and industrial emission (4%). Additionally, the spectral variation of the light absorption properties of black carbon (bBCabs) and brown carbon (bBrCabs), delta-C effect, and sensitivity of the AM are reported for the study period. The present study cautions that BC source apportionment can be complex in highly polluted metropolitan environments, and complementary tracer measurements are recommended for reliable results.

Sulfur Distribution Analysis in Lithium−Sulfur Cathode via Confined Inverse Vulcanization in Carbon Frameworks

AbstractLithium–Sulfur (Li–S) batteries are promising energy storage devices due to their high theoretical energy density. However, challenges such as the shuttling effect and volume expansion have significantly hindered their cycle life and capacity retention. Furthermore, the complex kinetic pathways in Li–S batteries call for advanced characterization techniques to unravel underlying mechanisms. In this study, a hollow porous carbon (HPC) is used as a microreactor, where inverse vulcanization occurs between 1,3‐diisopropylbenzene (DIB) and sulfur (S8), resulting in the creation of three‐dimensionally interconnected and well‐distributed S‐DIB in carbon frameworks. As a result, the dual confinement strategy imparts Li–S coin cells with remarkable cycling stability and capacity retention, exhibiting an impressive capacity of 866 mAh g−1 when returning to 0.1 C after 100 cycles of rate capability tests. Particularly, the Energy‐selective Backscattered (EsB) assisted Scanning Electron Microscope (SEM) technique as a novel approach is introduced to distinguish different lengths of polysulfides. Their distribution is visualized in the cross‐section view of the electrode in a micrometer range. These EsB images provide concrete indications of the sulfur evolution process and explain the capacity degradation during cycling.

Effects of ultrasonic shot peening followed by surface mechanical rolling on mechanical properties and fatigue performance of 2024 aluminum alloy

Aiming to improve the mechanical properties and fatigue performance of 2024 aluminum alloy, the experimental investigations on composite treatment consisting of ultrasonic shot peening (USP) followed by surface mechanical rolling (SMR) were carried out. The experimental results were compared with the specimens only treated by USP or SMR in terms of surface roughness, microhardness gradient and microstructure observation. The uniaxial tension test and low cycle fatigue test were conducted on the as-received specimen and the ones treated by USP, SMR and USP/SMR composite treatment, respectively. The tensile mechanical properties were effectively improved by USP. The introduction of SMR following USP can significantly increase the number of cycles to failure. Combining fracture morphology analysis and DEM-FEM coupling simulation of USP/SMR composite treatment, it was concluded that the improvement of tensile mechanical properties is mainly attributed to the synergistic effect of the compressive residual stresses and gradient-structured layer produced by USP, and the decrease in surface roughness resulting from SMR is the main reason for the significant improvement of fatigue performance. This work could provide an insight into the surface strengthening mechanism for USP/SMR composite treatment of materials with respect to the improvement of mechanical properties and fatigue performance.

Simulation Study on Factors Affecting the Output Voltage of Extended-Range Electric Vehicle Power Batteries

The power battery configuration of an extended-range electric vehicle directly affects the overall performance of the vehicle. Optimization of the output voltage of the power battery can improve the overall power and economy of the vehicle to ensure its safe operation. Factors affecting the output voltage of power batteries under different operating conditions, such as nominal voltage and the number of series and parallel connections of the battery cells, have been studied. This study uses AVL Cruise to establish an overall model of an extended-range electric vehicle to simulate the output voltage characteristics under the different operating conditions of the NEDC (New European Driving Cycle), WLTC (World Light Vehicle Test Cycle) and CLTC (China Light Duty Vehicle Test Cycle). The influence of the output voltage of the power battery under different operating conditions is studied to ensure that the power battery can output energy with high efficiency. The operating conditions have an impact on the output voltage with an idle voltage fluctuation of the operating conditions. The nominal voltage variation and the number of series and parallel connections of the battery cells affect the frequency and time of breakdown.

Assessment of VOCs emission inventory in Seoul through spatiotemporal observations using passive and online PAMS measurements

We have conducted a quantitative analysis of volatile organic compounds (VOCs) in Seoul from September 2022 to June 2023, employing passive air samplers (PAS) at 25 sites and continuous monitoring at five photochemical assessment monitoring stations (PAMS). Comparing VOCs concentrations and compositions from PAS and PAMS during the same time periods, we found that most VOCs showed no significant difference (p-value >0.05) between the methods, except for olefins, which were overestimated by 24 % in passive sampling, confirming PAS as an effective tool for assessing the spatial distribution of VOCs species over large areas. Throughout Seoul, median values of total volatile organic compounds (TVOCs) concentrations collected with passive samplers remained stable with a standard deviation of 1.22 ppbv, typically ranging from 11 to 13 ppbv, except for an increase during winter in the southwestern regions of the city, where intense industrial and vehicular emissions are reported in the current Clean Air Policy Support System (CAPSS) emissions inventory. Positive matrix factorization (PMF) analysis using the passive data revealed general consistency in the spatial distribution of area and road emissions when compared with CAPSS emission inventory, although localized discrepancies were observed. In quantitative assessments of TVOCs comparing PAS observations with emission-based models, modeled values were within 1.5 times the interquartile range of observed PAS concentrations over Seoul. However, the lack of detection of emission hotspots in southeastern Seoul in the PAS data, coupled with the omission of photochemical loss in our dispersion-only models, indicates that the current CAPSS emission inventory may significantly underestimate actual ambient VOCs levels, especially in summer.

Factors Determining the Selectivity of NO Reduction Catalyzed by Copper-Vanadium Oxide Cluster Anions Cu2VO3-5.

Catalytic NO reduction by CO is imperative to satisfy the increasingly rigorous emission regulations. Identifying the structural characteristic of crucial intermediate that governs the selectivity of NO reduction is pivotal to having a fundamental understanding on real-life catalysis. Herein, benefiting from the state-of-the-art mass spectrometry, we demonstrated experimentally that the Cu2VO3-5 - clusters can mediate the catalysis of NO reduction by CO, and two competitive channels to generate N2O and N2 can co-exist. Quantum-chemical calculations were performed to rationalize this selectivity. The formation of the ONNO unit on the Cu2 dimer was demonstrated to be a precursor from which two pathways of NO reduction start to emerge. In the pathway of N2O generation, only the Cu2 dimer was oxidized and the VO3 moiety functions as a "support", while both moieties have to contribute to anchor oxygen atoms from the ONNO unit and then N2 can be generated. This finding displays a clear picture to elucidate how and why the involvement of VO3 "support" can regulate the selectivity of NO reduction.

Simulation and mechanical testing of 3D printing shin guard composite materials

ABSTRACT This study critically examines the composite material's mechanical properties and performance for 3D-printed shin guards. It contains a thermoplastic polymer matrix with short carbon fibre reinforcement. Shin guard stress and deformation under impact loading were modelled using FEA models. The composite material was 3D-printed and tested for tensile, flexural, and impact properties. The entire cycle of FEA models and careful mechanical testing allows for the development and evaluation of new composite materials and designs. The finite element analysis, such as maximum von Mises stress, is 2890.5 MPa. The carbon fibre-reinforced composite's mechanical properties, including tensile strength, flexural strength, and impact resistance, showed a considerable improvement over those of the unreinforced polymer. The solid design could be heavier and less adaptable than the pattern. Compared to unreinforced polymers, carbon fibre improves strength, stiffness, and impact resistance for the 3D-printed composite. This result thus proves that 3D-printed carbon fibre-reinforced composites could make superior sports protective equipment like shin guards. The FEA calculations and extensive mechanical testing provide a dependable framework for creating and testing these new composite materials and systems.

Nacre-inspired graphene oxide/polyethyleneimine-based ultra-thin heterogeneous superwetting membrane for highly stable separation of oil-in-water emulsions

Since the massive discharge of oily wastewater seriously affects both humans and natural development, the performance of conventional membrane materials in terms of interfacial stability and antifouling in the treatment of surfactant-containing emulsified oily wastewater is a major challenge. In this work, a novel nacre-inspired graphene oxide/polyethyleneimine-based ultra-thin chemically heterogeneous superwetting membrane was fabricated through vacuum-assisted self-assembly and post-modification methods for oil-in-water emulsion separation. The nacre-inspired heterogeneous membrane exhibited superhydrophilicity, underwater superoleophobicity (underwater oil contact angle was 157.7°), excellent crude oil adhesion resistance, high acid/alkaline stability, outstanding salt resistance, and good mechanical properties (Young’s modulus 1391.7 MPa). The heterogeneous membranes showed separation efficiencies of more than 99.9 % for a range of oil-in-water emulsions. The high-value membranes could achieve the permeances of 917–1256 L m−2h−1 bar−1 for pure water and 339.7–577 L m−2h−1 bar−1 for emulsion through a dead-end filter device, with the optimal long-term stable permeance only decreasing by 30.0 % compared to the initial value. After six test cycles, the membrane’s antifouling and self-cleaning properties were enhanced by constructing heterogeneous superwetting properties, and the flux recovery rate remained at 96.5 %. All of these results indicated that this method provides new ideas for the design and fabrication of highly stable and antifouling membrane materials.

Computation of Particulate Emission Load from Vehicular Traffic on Road Network

The present study on traffic volume monitoring aims to compute total particulate emission load from urban road vehicular traffic and to find average emission factor. An industrial area Pandesara was selected as study area for its commercial and industrial activity, the contribution of public and private vehicle emissions in this area were high. Vehicle emissions include tailpipe emissions and road dust resuspensions. Tailpipe emission was the highest in off- road vehicles even their traffic volume was the least of all. Road dust resuspension due to vehicular speed was highest in 2 wheelers. Road dust resuspension concentrations due to silt fraction was found to be maximum in heavy motor vehicles. Total particulate matters concentrations emitted from vehicles and average emission factor were found to be 251616 gm/hr and 0.79 gm/Veh/Km respectively for entire Pandesara zone. Road dust resuspension plays a significant role in vehicular emission, still having less awareness among people worldwide. Keywords: Particulate Matter, Tailpipe Emission, Traffic Volume, Speed, Road Dust Resuspension, Turbulent Wake Height

Fuel consumption and exhaust emissions from Euro 6d vehicles fueled by innovative LPG/DME blend

The aim of this research was to investigate the exhaust emissions from vehicles when fueled by a new and fully renewable fuel if made of bio-LPG and renewable dimethyl ether (DME), in comparison with standard gasoline. For this purpose, DME was mixed with liquefied petroleum gas (LPG) and used to fuel three bi-fuel LPG/gasoline spark-ignition engines light-duty vehicles. The suitable fuel blend was selected based on several octane tests using CFR engines. Exhaust emissions were tested over the WLTC and over the hot-start CADC cycles, as well as on the road. All Euro 6 standards were well fully met over the WLTC with both fuels. Switching from gasoline to LPG/DME fueling, the CO and NOx emission factors increased for two vehicles, whereas THC and NMHC decreased. Regarding particulates, for two vehicles the emission factors decreased, too. Generally, when the vehicles were driven on the CADC, lower gaseous emissions were observed compared to WLTC: excluding one vehicle, when switching from gasoline to LPG/DME fueling, the overall emission profiles reflected those of the same vehicles run on the WLTC. The unregulated particulate emissions measured over both testing cycles reflect what was detected for the regulated ones. Except for PN10, which was not measured, all regulated emissions were found to meet the (most severe) Euro 7 standards proposed at first by the European Commission. RDE tests showed that all vehicle emissions obtained from on-road tests were also found to meet the RDE standards, regardless of the fueling. Concerning CO2 emissions, LPG/DME fueling guaranteed a systematic decrease for all vehicles and cycles, both on road and in the laboratory. The present investigation aims at demonstrating that the innovative LPG/DME 80 %/20 % (m/m) blend not only can be deemed as potentially suitable for GHG emissions reduction, as long as both DME and propane are obtained from renewable sources, but even compliant with EN 589 and both Euro 6 and part of preliminary Euro 7 exhaust emission proposal.

Real-world assessment of the energy consumption and emissions performance of a novel diesel-electric dual-drive locomotive

The huge demands for better energy efficiency and cleaner air from the public have driven governments to implement increasingly stricter emission standards. However, their implementation was not conducted uniformly among transport sectors. While road vehicles are now tested both in laboratory and real-world, rail vehicles are still only required to be tested in stationary conditions that have been shown to poorly reflect their real operation conditions. Therefore, this study aimed to assess the performance of a novel diesel-electric dual-drive locomotive in real-driving conditions. Significant variations were found for the tested locomotive in terms of both the share of idling time and the share of time the engine operated beyond the type-approval tests. The tested locomotive spent a similar share of time idling (24 %) as at its intended speed (60–90 km/h). It was found that 37 % of the particulate matter emissions were released during stops. Reducing the amount of time when the vehicle was accelerating at more than 0.5 m/s2, especially at speeds over 60 km/h, could reduce 50 % carbon monoxide emissions and 40 % hydrocarbon emissions. The findings suggest that incorporating the practice of eco-driving should be considered to significantly reduce the pollutant emissions from the railway sector.

Production of green methane by carbon dioxide capture from landfill biogas via pressure swing adsorption mediated by MOF ZIF-8

The growing interest in biomethane (bioCH4) as a sustainable replacement for conventional fossil fuels highlights the urgency to develop efficient CO2 capture methods from raw biogas, thereby enhancing the value of this renewable fuel source. This study investigates the efficacy of ZIF-8 as an adsorbent for CO2 capture through pressure swing adsorption (PSA) under non-isothermal conditions. ZIF-8 was synthesized and characterized using SEM, BET, FTIR, and XRD to understand and confirm its microstructures. A computational model was developed to simulate the dynamic behavior of ZIF-8 during adsorption, incorporating insights from its characterization. The model, based on the extended Langmuir model for multicomponent adsorption, also accounted for adjustments in the adsorption bed geometry. Dynamic simulations were performed employing the Aspen Adsorption platform to assess the impact of key parameters such as the CH4/CO2 ratio, length/diameter ratio, and adsorption time on bioCH4 purity. Utilizing the Design of Experiments framework, central composite design (CCD), and desirability functions, the interplay of these parameters was optimized to enhance bioCH4 purity and recovery rates. The optimized PSA system, utilizing ZIF-8, demonstrated impressive purity of 99.93% and recovery of 96.5% at CH4/CO2 ratio of 2.06, a length/diameter ratio of 2.76, and an adsorption time of 115 s. These results meet stringent quality criteria for vehicle fuel, aligning with the most rigorous emission standards. For future investigations, it is crucial to explore the long-term stability and regeneration capabilities of ZIF-8 in large-scale applications. Understanding its practical feasibility and sustainability as an adsorbent for biogas upgrading will provide valuable insights for further advancements in this field.

Simultaneous measurement of SO2 and CO2 for sulfur content detection in marine diesel fuel using QCL absorption spectroscopy

Simultaneous measurement of CO2 and SO2 in ship exhaust gases is a common method for assessing compliance with sulfur emission standards. This study develops a new ship exhaust gas analyzer using time-division multiplexing of two quantum cascade lasers for simultaneous detection of the two gas species. A digital circuit integrated with a dual-channel waveform generator and a lock-in amplifier is developed to implement wavelength modulation spectroscopy (WMS) scheme. To enhance the measurement accuracy of SO2 with broadband absorption feature, a novel WMS approach that combines first-harmonic and normalized second-harmonic detection is introduced. A Kalman filter algorithm is employed to further refine the measurement precision. Experimental results show a 30.76% increase in detection accuracy. With a 1 s time resolution, the sensitivities of 13.4 ppb for SO2 and 9.81 ppm for CO2 are achieved. The effectiveness of the prototype for sulfur content detection is demonstrated, aiding emission management of water transport emissions.

Loudness and preference judgments for noises of a heat pump

An increasing number of heat pumps have recently been installed to replace conventional heating systems to provide more environmentally friendly and energy-efficient indoor heating. Most commonly, air-to-water heat pumps are chosen. However, the sounds of their fan and compressor can lead to noise complaints and can reach the limit of noise emission regulations. To achieve a more pleasant environment, research is conducted to reduce the perceived noise of heat pumps. As part of an interdisciplinary research project, this study aims to investigate the annoyance ratings of a heat pump and characterize them in terms of equivalent loudness and preference penalties. The study uses a two-alternative forced-choice (2AFC) method with a 1-up-1-down rule to measure the point of subjective equality for six stimuli representing different operation states of the investigated device. This experiment aims to identify differences between loudness and preference, and combined with an evaluation of psychoacoustic parameters, its results are used to improve the acoustics of heat pumps and the overall user experience.

Decarbonizing urban passenger transportation: Policy effectiveness and interactions

The urban passenger transportation plays a pivotal role in achieving ambitious climate targets. Exploring its opportunities for decarbonization requires a comprehensive understanding of the impacts of different policy designs. This study develops an integrated model for simulating the effectiveness and interactions of various policy designs aimed at decarbonizing urban passenger transportation. It distinguishes itself from previous studies by considering a broad range of criteria, including mitigation effectiveness, cost effectiveness, and transition effectiveness. It also assesses the overall performance of various policy options based on these effectiveness criteria. In an urban case study, we have identified the complementary nature of the majority of policy mixes and also revealed conflicting effects when implementing a supplementary policy, such as carbon tax and fuel economy regulation. The concurrent implementation of multiple policies can yield synergistic effects or trade-offs, with the former being widely acknowledged in the context of energy transition, while the latter is more commonly observed in relation to emissions reductions and cost savings. This study also reveals a trade-off effect across various effectiveness criteria, underscoring the significance of formulating well-balanced policy packages to promote sustainable urban passenger transport.

ZIFs@MIL-101/urea-derived magnetic FeCo nitrogen-rich carbon as an effective and stable catalyst for peroxymonosulfate activation

High efficiency and stability are key issues in heterogeneous metal catalytic materials/peroxymonosulfate (PMS) systems during wastewater degradation. However, catalytic materials that are difficult to recover and metal leaching can cause secondary contamination of water bodies. Herein, we designed the magnetic FeCo nitrogen-rich carbon (FeCo-NC) obtained by layer-by-layer encapsulation, followed by urea encapsulation of in situ grown MOF-in-MOF and carbonization. The CoFe2O4 crystalline nature of FeCo-NC was confirmed by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and selected angle electron diffraction (SAED) results, which is responsible for the magnetic properties of FeCo-NC. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) present that the material's morphology transforms from dodecahedral ZIF-67 to spindle-shaped ZIF-67@MIL-101 and then to octahedral FeCo-NC. Compared with FeCo-C and ZIF-67@MIL-101, the removal efficiency of FeCo-NC was maintained at 78.6 % after 10 consecutive cycles, with only a 17 % loss of raw material. The Fe and Co leaching amounts in the FeCo-NC/PMS system were approximately 0.6 and 0.1 mg/L, respectively, much lower than China's Fe and Co emission standards. FeCo-NC characterization and TC degradation results demonstrated that magnetic CoFe2O4 nanoparticles formed on the surface or inside the FeCo-NC could effectively inhibit metal (Fe and Co) loss and be easily regenerated in multiple degradation cycles. The mechanism and degradation routes in the FeCo-NC/PMS/ TC system, including the radical/nonradical pathways, Fe/Co valence change, and electron transfer, were further investigated by electron paramagnetic resonance experiments, electrochemical analyses, in situ Raman spectroscopy, and HPLC–MS experiments.