Hydrothermal carbonization (HTC) is a promising technology for the coversion of swine manure (SM) for hydrochars (HCs). Currently, information on the humification of organic matter is limited during the HTC of SM, and its potential correlation with the passivation of heavy metals (HMs) remains unclear, which is crucial referece for the land application of SM-derived HCs. This study systematically investigated the humification of organic matter and the passivation of HMs during the HTC of SM and then explored their intrinsic connection. The HTC treatment can enhance the humification of organic matter, and the HCs obtained at 240 ℃ had the best humification effect, with the highest content of humus (83.84 mg·g^-1 versus 41.97 mg·g^-1 in SM) and humification rate (28.89% versus 15.73% in SM). Dissolved organic carbons (DOC) and readily oxidized organic carbons (ROC) were more easily degraded in the HTC of SM, and part was further converted into inactive organic carbon. HMs (Cu, Zn, Pb, and Cr) were enriched in HCs, but all HMs were largely passivated. The ecological risk of multi-HMs was reduced from moderate risk in SM to low risk in HCs. The percentages of HMs in exchangeable/acid-soluble forms were positively correlated with the contents of DOC and negatively correlated with the ratio of humic acids to fulvic acids (P < 0.05). It was inferred that the humification of organic matter promoted the passivation of HMs in the HTC of SM. This study provided deeper insights into the humification of organic matter and it's intrinsic correlation with HMs-passivation during the HTC of SM.

Understanding and predicting droplet breakup is essential in droplet-based microfluidic systems, as it enables precise control over droplet manipulation for various applications. In this study, droplet breakup behavior in a T-junction microchannel is investigated under the influence of microchannel geometry using three-dimensional numerical simulations. A theoretical model is developed based on the balance between surface tension and viscous drag forces acting on the droplet, incorporating the effects of geometric parameters on droplet length. This model predicts the critical Capillary number required for breakup to occur. The theoretical predictions are validated using both previous research data and the present numerical simulations. The results show that the model accurately predicts the transition between breakup and non-breakup regimes. Specifically, an increase in sidearm length ratio inhibits droplet breakup and leads to an asymmetric breakup regime. Furthermore, increasing the outlet-to-inlet width ratio also reduces the likelihood of droplet breakup. These findings provide a predictive framework for understanding and controlling droplet dynamics in microfluidic T-junctions, with potential applications in lab-on-a-chip technologies.

A promising structured catalyst was developed through proper coating of boron-modified ZSM-5 using SiO₂ and Al₂O₃-containing binders to investigate catalytic performance as well as mechanical stability of the catalyst in a monolithic reactor. The reference and boron-modified ZSM-5 catalysts were synthesized by hydrothermal route. The adherence strength of catalyst samples was characterized using ultrasonic vibration method and FESEM analysis. A series of comparative performance tests were also conducted in two reactors, including monolithic and extruded catalysts for the production of propylene from methanol at atmospheric pressure, reaction temperatures of 500 ℃, and methanol weight hourly space velocity (WHSV) of 1.5 h^-1. Initial findings demonstrate that applying the B-modified ZSM-5 zeolite in a monolith reactor increased propylene selectivity by about 26% compared to the conventional extruded ZSM-5 catalyst. Moreover, silica bonded to the B-ZSM-5 catalyst in the monolithic reactor, owning sufficient adhesion properties; the proposed catalyst showed the best catalytic performance, with not only a high propylene selectivity (58.5%) but also a large propylene/ethylene (P/E) ratio (8.6). The findings attained in this work would be useful in the production of new efficient catalysts based on a zeolite-coated honeycomb monolith in the methanol-to-propylene process.

Municipal sludge, a sewage treatment by-product rich in nitrogen (N) and phosphorus (P) — essential soil nutrients — is limited in traditional composting due to heavy metal contamination. Thermochemical treatments offer a promising alternative, but the migration pathways of N and P during these processes, and how to enhance nutrient recovery while mitigating heavy metals, remain unclear. This study investigates N and P migration in sludge via incineration, hydrothermal carbonization (HTC), and pyrolytic gasification, focusing on key mechanisms and optimization. Results show incineration and pyrolytic gasification suffer from significant N loss (as NO_x or low-concentration ammonia) and limited P availability, while HTC uniquely retains N and P in both solid (up to 14.03% N, 11.53% P) and liquid (26.74 g·kg^-1 N, 64.69 g·kg^-1 P) products under mild conditions, with heavy metals stabilized in its weak oxidizing atmosphere. A critical innovation is that adding calcium (Ca) and magnesium (Mg) in HTC promotes plant-available N/P compounds (e.g., Ca₅(PO₄)₃Cl, NH₄MgCl₃·6H₂O) and reduces toxic heavy metals to 0.229%. Temperature-dependent selectivity is observed: 210 ℃ with MgCl₂ enhances N/P conversion (up to 71.72% N, 61.3% P), while 270 ℃ with CaCl₂ prioritizes heavy metal stabilization. This work clarifies N/P migration mechanisms, establishes an additive-temperature regulation strategy for simultaneous nutrient recovery and detoxification, and provides a theoretical basis for sludge utilization as high-value fertilizer precursors.

This study presents a systematic investigation of pressure drop and gas holdup in an upward-flow fixed-bed reactor, examining the effects of bubble size, bed height, particle shape, superficial gas velocity (SGV), and superficial liquid velocity (SLV) based on experimental measurements and empirical correlations. Two bubble generators, namely ring tube generator (RTG) and porous sintered film generator (PSG), are used. Key findings reveal that for the PSG, increasing SGV decreases small-bubble population while promoting large-bubble formation, with the bubbles stabilizing at a Sauter mean diameter (d₃₂) of ~3 mm. The RTG produces stable large bubbles (d₃₂ = 6-7 mm) with minimal size variations across the range of tested SGVs. The pressure drop decreases with an increase in SGV but increases with higher SLV and bed height, primarily due to the reduced liquid holdup and the dominance of static pressure. Smaller bubbles reduce the pressure drop by slowing rise velocity and minimizing frictional resistance. Clover-shaped particles exhibit the highest pressure drop owing to large porosity, while 3-mm toothed spheres show higher pressure drop than 5-mm spheres at high SGV because of intensified capillary forces. The gas holdup increases with increasing SGV and bed height but decreases slightly with increasing SLV. Smaller bubbles enhance gas holdup by improving bed distribution and residence time. The 3-mm toothed spheres show the highest gas holdup due to stronger capillary trapping, whereas the clover-shaped particles exhibit the lowest. Empirical correlations for pressure drop and gas holdup are developed, yielding calculation errors within ±1% and ±20% of the experimental values, respectively.

This study develops a CFD-ML integrated framework to achieve multi-objective optimization for the partial oxidation of n-butane to maleic anhydride (MA). A reactor-pellet coupled model was established to investigate the effects of four key operating parameters, revealing that inlet temperature dominates reactor performance by increasing MA yield from 35.0% to 37.6% while sharply raising hotspot temperatures by 42 K. The coupled model was then employed to generate 621 cases for training machine learning models, among which the Gaussian Process Regression (GPR) model exhibits superior accuracy. The GPR model was further integrated with the genetic algorithm to generate Pareto-optimal sets. The results indicate that a critical inflection point is identified on the Pareto front, and once this point is exceeded, even a slight increase in MA yield could lead to a sharp rise in the reactor hotspot temperature, thereby increasing the risk of thermal runaway.

Nano-silica grease (NSG), an innovative lubricant, is commonly synthesized using base oil thickened with SiO₂, the choice of appropriate base oil is crucial for obtaining superior performance NSG. Herein, a series of alkylnaphthalene (AN) base oils with different side-chain lengths were synthesized through the alkylation reaction between naphthalene and α-olefin. We first reported the synthesis of NSGs based on the AN base oils, and investigated the influence of the synthetic AN base oils on the rheological behaviors and tribological characteristics of the resulted NSGs. The results indicated that the structural strength of the grease increased as the alkyl chain length rose because it reinforced the contact between the alkylnaphthalene base oil and nano-silica thickener. Meanwhile, tribological tests were conducted to examine the effect of various AN base oils on the lubricating performance of the formed NSGs. The tested results showed that increasing the side chain length of the AN could elevate the friction-reducing and anti-wear properties of the NSG.

Normal diffusion flame (NDF) of acid gas with a H₂S concentration below 50.0% (vol) generally exhibits a low flame temperature in a low-level oxygen enrichment atmosphere under Claus conditions, resulting in flame instability. This research proposed that inverse diffusion flame (IDF) was applied to acid gas combustion for enhancing flame temperature. IDF of acid gas was compared with fuel gas co-combustion (FGC), split flow of acid gas (SFAG) and high-level oxygen enrichment combustion (OEC). Additionally, the effect of CO₂ addition on the IDF of H₂S was investigated. The results indicated that a stable flame could be observed in the IDF of acid gas, its peak flame temperature was about 801.0 K, which was higher than that in the OEC, FGC and SFAG with a value of about 591.0, 684.0 and 734.0 K, respectively. IDF of acid gas was contributed to the formation of sulfur and H₂, and mainly involved the oxidation zone and the chemical decomposition and oxidation zone in sequence. In the IDF, CO₂ exhibited a better oxidation performance, and the peak flame temperature was decreased by about 21.0 K with an increase in CO₂ addition from 50.8% to 59.5% (vol), whereas significantly enhanced the oxidation reaction rate of H₂S, and the peak volume fraction of SO₂ was increased from 5.812% to 7.075%. The application of IDF to acid gas combustion achieved the objective for improving flame temperature in low-level oxygen enrichment atmosphere under Claus conditions, providing a new perspective in the sulfur recovery and hydrogen production from acid gas.

To synchronously achieve the rational use of biomass resources and the design of highly efficient Cu₂O-based photocatalysts, the Ag/CQDs/Cu₂O was synthesized by hydrothermal process, where the CQDs were derived from waste biomass. The TC-HCl degradation efficiency could reach 95.08% with a 0.2 g·L^-1 dosage of Ag/CQDs/Cu₂O, much higher than that of pristine Cu₂O (48.60%) and Ag/Cu₂O (66.97%). Mechanism exploration revealed the key roles of Ag NPs and CQDs in complex photocatalysts where multiple synergistic pathways greatly enhanced the generation and separation of photocarriers. The convert-light via CQDs matched for Cu₂O could induce more photocarrier generation. Meanwhile, the Schottky barriers between Cu₂O and Ag NPs and the electron reservoir properties of CQDs accelerated the separation of electron-hole pairs. The effects of catalyst dosage, various concentrations of TC-HCl, coexisting anions and humic acid and pH value have been studied as well. Tapping experiments and electron spin resonance (ESR) identified that the ·O₂^- and ·OH were the main active species during photodegradation process. Additionally, the underlying degradation process of TC-HCl in Ag/CQDs/Cu₂O photocatalytic system was revealed by theoretical calculation and HPLC-MS. This work will provide a new perspective for future material design and research on enhancing heterologous catalysis oxidation process.

Phenolic resin-based porous composites are the promising thermal protection materials for aerospace applications. The high-temperature evolution of microstructure due to the decomposition of the resin also presents great challenges to predict the internal heat and mass transport behaviors. This work investigates the effects of microstructural characteristics such as the number of pores, size distribution, pore-throats size and volume fraction on the permeation behaviors of fluid in the needle-punched short-cut fiber reinforced silicon phenolic resin-based porous composites. The specimens are prepared by the sol-gel method and the atmospheric pressure drying process and the pyrolysis experiment are conducted at 400 ℃ and 800 ℃. Then, a scanning electron microscope and a Nano-CT computer tomography are applied to obtain the surface morphologies and the interior slice images of the specimens. The AVIZO software is employed to accurately extract and analyze the pore structural model and simulated calculate the absolute permeability. It is found that the small pores develop gradually during pyrolysis due to the resin decomposition and the quartz fibers rearrangement, resulting in an increase in number of large pores. Nonetheless, the equivalent radii of most pores are less than 1 μm. Very few pores possess a large radius over 5 μm. However, the volume fraction of these large pores exceeds 99%. In addition, with the pore size growing, the connectivity between these pores is enhanced, immediately causing an increase in number and size of the pore-throats. Larger pore and more pore-throats would add the unblocked flow channels for the fluid passing, reducing flow resistance. The seepage simulation also confirms that the absolute permeability gains significant increase after pyrolysis in all directions. For example, the absolute permeability of the pyrolyzed sample is 9.0×10^-13 m² in X direction, which is an order of magnitude greater than that of the unpyrolyzed sample. This study provides important insights for understanding the high-temperature evolution at of microstructure and the permeation behavior of fluid in porous thermal protection materials.

Conventional steam reforming for hydrogen production is limited by the thermodynamic equilibrium. To address this limitation, in this study, a cost-effective catalyst-sorbent hybrid material was synthesized from waste steel slag and limestone. A 30-cycle CO₂ sorption experiment and a sorption-enhanced biomass reforming for hydrogen production experiment were conducted. The results indicate that for the A₄L₃S₂ (4 mol·L^-1 acid, limestone: slag = 3:2) composite, it attains a total CO₂ sorption capacity of 4.14 g·g^-1 under mild conditions, with only a 23.5% reduction after 30 cycles. Moreover, under severe conditions, it manages to retain 3.81 g·g^-1 in total 30 cycle. When applied to sorption-enhanced biomass gasification using pine wood shavings, the material significantly boosts hydrogen production, achieving a hydrogen purity of 74.57% and a yield of 0.818 mmol·g·g^-1·min^-1, while reducing the CO₂ concentration in the syngas to 10.89%. These findings highlight the dual functionality and robustness of the steel slag-derived material, offering a cost-efficient and environmentally sustainable pathway for industrial hydrogen production and valorization of solid waste resources.

Saccharomyces cerevisiae is not naturally capable of efficiently utilizing xylose as a carbon source. When cultured with lignocellulosic hydrolysates containing pretreatment-derived inhibitors, S. cerevisiae suffers from much lower sugar uptake, ethanol yield and fermentation efficiency. Thus, considering efficient xylose conversion into ethanol during non-detoxified hydrolysate culture, genetic engineering and adaptive evolution of S. cerevisiae might be a promising joint strategy for improving xylose uptake and ethanol production. In this study, an inhibitor-tolerant strain S. cerevisiae SPSC01-TAF94 was genetically engineered by overexpressing both xylose transport- and metabolism-related genes (N360F, Ru-xylA, TAL1, TKL1, RKI1 and RPE1), yielding the xylose-utilizing strain TAF94-X, followed by three-stage adaptation in non-detoxified corn stover hydrolysate containing 5 g·L^-1 acetic acid, 0.32 g·L^-1 furfural, 0.17 g·L^-1 HMF and 0.19 g·L^-1 vanillin as the major inhibitors as well as 20, 40 and 60 g·L^-1 xylose adjusted as the major carbon source, respectively. Finally, an active xylose-utilizing and ethanol-producing strain TAF94-X60 was obtained, which achieved 44.9 g·L^-1 ethanol with yield of 0.41 g·g^-1, productivity of 0.62 g·L^-1·h^-1 and xylose consumption rate of 0.42 g·L^-1·h^-1 during hydrolysate culture, compared to those of 36.5 g·L^-1, 0.38 g·g^-1, 0.50 g·L^-1·h^-1 and 0.20 g·L^-1·h^-1 obtained with the control strain TAF94-X. The proposed joint strategy effectively utilizes hydrolyzed sugars while eliminating the need for conventional detoxification or water washing processes, thus enhancing the economic feasibility of large-scale lignocellulosic ethanol production.

Electrolytic reduction is a crucial process during the pyroprocessing of oxide spent fuel. This paper investigates the effects of different concentrations of Li₂O on the properties of the LiCl-UCl₃-Li₂O molten salt system during electrolytic reduction using first-principles molecular dynamics simulations. The study reveals that increasing Li₂O concentration lowers the ion diffusion coefficients of Li⁺, Cl^-, and O^2- in the electrolyte, which has negative effect on the transport property of the system. A thorough analysis of the ligand structures formed by various components in the molten salt was conducted, including radial distribution functions and angular distribution functions. The analysis reveals that oxygen ions compete with chloride ions for coordination with cations. This competitive interaction has a significant impact on the coordination between Li-Cl and U-Cl elements, thereby influencing the microstructure. The analysis of electronic structures shows that the addition of Li₂O affects the charge transfer among lithium, uranium, and chlorine, impacting the bond strength between anions and cations. Finally, the calculation of redox potential shows that an appropriate concentration of Li₂O is beneficial to the electrochemical reduction process. The research results provide a theoretical basis for the design of molten salts in the electrolytic reduction process.

Intramolecular [2 + 2] photocycloaddition is a reliable way to synthesize high-strained cyclobutyl-containing structures for high-value chemicals. Here we propose a photosensitized dimer of methyl cyclopentadiene (DMCPD) intramolecular [2 + 2] cycloaddition to synthesize an intriguing liquid caged fuel, namely 3,8-dimethylpentacyclic [5.3.0.0^2,5.0^3,9.0^4.8] decane (MPCD), with two four-membered rings, four five-membered rings and two methyl branched chains. The reaction conditions are optimized to obtain a high DMCPD conversion of 80.95% as well as a high MPCD selectivity of 74.19%. Based on the quenching experiment and low-temperature phosphorescence test, intramolecular [2 + 2] photocycloaddition complies with the Dexter triplet-energy-transfer mechanism, which is essentially double electron exchange between excited photosensitizer and DMCPD. Through kinetic studies, the reaction order (α = 1) and the reaction kinetic equation related to light intensity and DMCPD concentration are obtained. MPCD has excellent physicochemical properties, with a high density of 0.964 g·cm^-3, high net heat of combustion of 42.63 MJ·kg^-1, relatively low kinetic viscosity of 25.03 mm²·s^-1 at (20 ℃), and high specific impulse of 328.19 s.

Zinc-ion capacitors have gained significant interest because of the exceptional capacity of zinc, the safety of aqueous electrolytes, and the low cost of carbon materials. However, the low capacity of carbon materials greatly limits the energy density of the capacitors. Structural modification or introduction of heteroatom doping to carbon materials sacrifices their volumetric density and cycling stability. Here, we introduce soluble methylene blue (MB) into the electrolyte of the carbon electrode to enhance the capacity by utilizing its redox reactions at the interface. Adding MB increases the electrode capacity to 118 mA·h·g^-1, 3.8 times higher compared to that without MB. Importantly, AC electrode with MB delivers an ultrahigh cycling stability with a retention of 90% after 12000 cycles. In situ and ex situ characterization indicates that MB undergoes reversible structural changes during the processes. Theoretical calculations further demonstrate that the reaction of MB discharging process involves two electrons and two protons, going through a radical intermediate state. Assembled Zn//AC capacitor with MB achieves a maximum capacity of 137 mA·h·g^-1, 3.4 times higher compared to the capacitor without MB. Additionally, the capacitor with MB exhibits an energy density of 105.8 W·h·kg^-1, three times higher than that without MB. Moreover, the capacitor exhibits outstanding cycling stability, retaining 92% of the capacity even after 8000 cycles. Our results demonstrate that MB can effectively promote the energy density of the capacitor without sacrificing its cycling stability.

Polymer fibers are among the most promising adsorbents in wastewater treatment, while limited by poor adsorption capacity and irreversible pollution. Herein, amine-modified C₃N₄/TiO₂-polyacrylonitrile (PAN) composite fibers with high absorption ability and photocatalytic self-cleaning properties were fabricated via wet spinning. The introduction of diethylenetriamine (DETA) onto the PAN resulted in the presence of positively charged amino groups, which not only increased the number of adsorption sites for anionic dyes but also facilitated the formation of a sponge-like pore structure. Optimally, the adsorption capacity of the aminated PAN fibers (PD7h) for methyl orange (MO) reached 164.79 mg·g^-1, which is 39.2 times greater than that of unmodified PAN fibers. Furthermore, the introduction of the C₃N₄/TiO₂ heterojunction photocatalyst endowed the fibers with photocatalytic self-cleaning capability by generating active free radicals (hydroxyl radicals (·OH) and superoxide radicals (·O₂^-) that efficiently degraded dye pollutants in situ on the fiber surface. Under irradiation using a 300 W xenon lamp, the aminated C₃N₄/TiO₂-PAN fibers (PDCT-1) removed more than 90% of MO (30 mg·L^-1) within 120 min. After eight cycles, the pollutant removal rate decreased by only 22.41%, indicating excellent stability. Overall, this work presents an effective, simple and feasible method for preparing polymer fibers with high adsorption and photocatalytic self-cleaning properties via wet spinning for dye wastewater treatment.

GO membranes with well-defined sub-nanometer channels are optimal for desalination and wastewater purification. However, the inherent instability of the interlayer structure and the severe trade-off between selectivity and permeability pose a significant challenge for GO membranes to be effectively applied to nanofiltration. Herein, we synthesized a series of PSSNa-GO-EDA/Al₂O₃ membranes by embedding poly(sodium 4-styrenesulfonate) (PSSNa) into ethylenediamine-crosslinked GO interlayers. The resultant membranes exhibited greater interlayer structures, in which new hydrophilic confined nanostructures were constructed. Effective nanofiltration performance was achieved through electrostatic-induced ion-confined partitioning. The PSSNa-GO-EDA-1/Al₂O₃ (PGE-1) membrane showed high rejection rates of 86.0% for Na₂SO₄ and 53.8% for NaCl while maintaining competitive pure water permeance of 10.85 L·m^-2·h^-1·bar^-1 (1 bar = 0.1 MPa), which is 12.1 times higher than that of the pristine GO membrane. More importantly, after immersion in pure water for 680 h, this membrane retained commendable separation performance. Overall, our work provides an effective strategy to finely fabricate confined nanostructures in lamellar GO-based nanofiltration membranes featuring excellent separation performance.

To ensure the safe operation of batteries, accurately obtaining key internal state parameters is essential. However, traditional parameter measurement methods either require opening the battery or long-term measurements, which are impractical. Therefore, the fixed values are commonly used for these parameters in electrochemical models and have significant limitations. To overcome these limitations, this paper proposes a deep neural network (DNN) based data-driven evaluation method to determine model parameters. By coupling an improved one-dimensional isothermal pseudo-two-dimensional (P2D) model with DNN, this study identified concentration-dependent parameters through detailed discharge curve analysis. The results show that the data-driven method can effectively obtain the change trend of concentration-dependent parameters through the charge and discharge curve, and the method can be extended to different battery systems in different discharge rates and aging applications. This work is expected to provide new parameter selection insights for data-driven battery prediction and monitoring models.

Hollow fiber membrane contactor (HFMC) units are one of the most promising technologies for improving conventional absorption processes. Traditionally, the optimization and control of this process is based on simplified mathematical models or linearized control proposals that may present limitations. This work introduces a robust control based on modeling error compensation (MEC) applied to CO₂ and H₂S absorption in a HFMC for natural gas sweetening. The HFMC model considers the concentration distribution in radial and axial coordinates. A classical PI controller and a sliding model controller (SMC) are applied for comparison purposes. Simulation results show that the proposed control MEC is suitable for regulating the sour gas concentration to values that reduce their presence at the HFMC from 0.85% to 0.45% (mol) of CO₂ and from 4 to 1.2 μl·L^-1 of H₂S, independent of external disturbances and setpoint changes. Likewise, MEC’s ability to compensate for modeling uncertainties through a simple and easily implemented design provides robust performance that satisfies international standards in natural gas quality, showing a 40% better performance according to the integral of squared error compared with the SMC controller.

Granular bed filter is one of the most promising technologies for the dust removal from high temperature coal pyrolysis gas. In this work, three-dimensional numerical models were employed to investigate the influence of operation parameters on collection efficiency, especially paying attention to particle deposition characteristics in the bed and outlet particle size distribution. The results show that the operation parameters have different effects on the collection efficiency of particles with the different properties. Under the same conditions, the collection efficiency of granular bed for circulating ash increases more rapidly compared to that of char particles. According to the effective Stokes number (N_steff), the collection efficiency of granular bed can be obviously divided into three regions: difficult separation region (N_steff≤0.25), transition region (0.25<N_steff<0.83) and easy separation region (N_steff≥0.83). Dust deposition within the bed exhibits axial attenuation along the gas flow direction, allowing classification of deposited particles into two characteristic types: dispersed particles and congregated particles. In addition, granular bed filtration induces a morphological transition of particle size distribution, transforming the original monomodal profile into a well-defined bimodal structure. A correlation formula of the collection efficiency was developed, providing critical insights for the engineering design of granular bed filters.

Source term estimation (STE) of hazardous gas leakages in chemical industrial parks (CIPs) is important for addressing environmental pollution and improving safety and reliability in engineering practice. To achieve real-time STE, least squares-based STE methods have recently been developed. However, these methods require the number and locations of potential hazardous gas leakage sources are known as a priori, which is difficult in many practical scenarios. To address this limitation, we propose a new data-driven STE approach, which enables the STE to be implemented in real time and applicable to complicated turbulent dispersion scenarios. The linear independent analysis in data science is applied to historically collected concentration data of a hazardous gas of concern from a network of sensors to extract the sensor data which represent independent hazardous gas leakage scenarios (IHGLSs). An appropriate Gaussian model approximation to a high-fidelity computational fluid dynamics (CFD) model that must be used to represent the hazardous gas leakage scenarios of concern is built, and the off-line STE of IHGLSs using the approximating Gaussian model is then performed to build the data-driven STE model. The performance of the proposed approach is evaluated by using data that are generated by simulating ethane leakage scenarios in a CIP using a CFD model. Results indicate that the leakage localization accuracy is 100% and the mean relative estimation error for the leakage strength is 6.76%. Moreover, the proposed approach is validated with real data in Prairie Grass field dispersion experiments, demonstrating the practical applicability of the proposed approach.

Non-solvent induced phase separation (NIPS) is one of the most used methods for the preparation of PAN membranes. Predicting the pattern of change in membrane structures remains a key issue. A binodal line procedure about PAN/solvent/non-solvent was established for it by Flory-Huggins theory. Calculation of non-solvent-polymer interaction parameter (χ₁₃) by the osmotic pressure method combined with the Rudin model and the equilibrium dissolution method. Solvent-polymer interaction parameter (χ₂₃) by viscosity method. Then, the solvent-nonsolvent interaction parameter (g₁₂) equation is obtained by combining the modified Flory-Huggins free energy. Finally, the accuracy of the model was verified by cloud points experiments and membrane structures. It was found that when mixed non-solvents were used, the binodal line moved to 100% of the added component. Changes in membrane structure coincide with changes in phase diagrams when changing solvent and non-solvent species and temperature. Based on the combination of experiment and theory we obtained the maximum water flux of membranes was increased to 2217.47 L·m^-2·h^-1·bar^-1 with the addition of additives PEG and SiO₂ with DMF/PAN/H₂O system. The average permeate flux over 0.75 h reached 387.12 L·m^-2·h^-1·bar^-1 (1 bar = 0.1 MPa) with 82% flux recovery. The hexadecane oil-in-water emulsion have confirmed that the membranes showed prominently high retention rate achieved 99% for oil.

Developing selective electrodes for lithium extraction from brines remains challenging. This work reports room-temperature synthesized cubic copper hexacyanoferrate (CuHCF) nanoparticles for hybrid capacitive deionization (HCDI). The CuHCF framework exhibits a high surface area (715.84 m²·g^-1), dual redox-active sites ([Fe^III(CN)₆]^4-/[Fe^II(CN)₆]^3- and Cu⁺/Cu²⁺), and excellent cyclability (99.4% capacity retention after 1000 cycles). In HCDI system, the CuHCF cathode demonstrates remarkable Li⁺ ions selectivity, achieving a 25.5 mg·g^-1 adsorption capacity in 500 mg·L^-1 LiCl solution with 94% charge efficiency at 1.2 V. Notably, in mixed Li⁺/Mg²⁺ solutions (30:1 molar ratio), CuHCF nanoparticles maintain a high separation coefficient of 3.1, attributed to the synergistic effects of ionic sieving and preferential redox interactions. Mechanistic studies confirm Li⁺ (de)intercalation via reversible [Fe^III(CN)₆]^4-/[Fe^II(CN)₆]^3- and Cu²⁺/Cu⁺ transitions. Density functional theory calculations reveal Li⁺ exhibits lower adsorption energy than Mg²⁺ (-3.72 eV vs. -1.49 eV), which fundamentally explains the preferential extraction capability of Li⁺ ions over Mg²⁺ ions during the separation process. This study advances ion-selective pseudocapacitor design for sustainable lithium extraction from high-salinity resources.

The current vanadium extraction process from sodium roasted vanadium slag poses risks such as ammonia pollution. This study proposes a novel calcium-based vanadium extraction and hydrolysis precipitation process, achieving clean and efficient vanadium recovery. The introduction of CaO facilitates the targeted reconstruction and conversion of vanadium and calcium in the solution, forming acid-soluble calcium vanadate intermediates. Under optimal conditions, n(Ca)/n(V) ratio of 1.75, extraction temperature of 90 ℃, and extraction time of 90 min, the vanadium extraction ratio reached 99.83%. This process also separates vanadium from sodium and silicon, enabling one-step purification of the vanadium solution. Subsequent sulfuric acid leaching, conducted at pH of 4.0, 90 ℃, and 60 min, achieved a vanadium leaching ratio of 99.72%, further separating vanadium from calcium and other impurities. Finally, the purified vanadium solution underwent hydrolysis precipitation at pH of 2.1 and 95 ℃ for 60 min, achieving a precipitation ratio of 98.69%. The calcined product yielded V₂O₅ with a purity of 98.60%. Compared to the conventional sodium roasting-water leaching along with ammonium salt precipitation process, this innovative method eliminates ammonia-nitrogen wastewater emissions. This study provides a foundation for the development of new vanadium extraction technologies from vanadium slag.

The preparation of high-strength α-hemihydrate gypsum (α-HH) from dihydrate gypsum (DH) is a potential way to improve the utilization rate of industrial gypsum. α-HH with a low aspect ratio was prepared by atmospheric salt solution method, using Mg(NO₃)₂ solution as the salt medium. The effects of reaction temperature, reaction time, Mg(NO₃)₂ concentration, pH value, and the solid-to-liquid ratio on the purity, yield and aspect ratio of the product were investigated systematically. Under the optimal reaction conditions of 95 ℃, 4 h, 40% (mass) Mg(NO₃)₂, pH 5, and a solid-liquid ratio of 1:5, the yield and purity of the product could reach 89.67% and 99.85%, respectively. Additionally, the average aspect ratio of this product was 2.02, and the compressive strength reached 58.2 MPa. The regulation mechanism was studied by calculating the adsorption energies of Mg(NO₃)₂ on different crystal planes of α-HH, which indicated that Mg(NO₃)₂ exhibited the strongest adsorption on the (1 1 1) plane, and this preferential adsorption retarded the axial growth of α-HH, resulting in a reduced aspect ratio of the crystals. These findings suggest that the Mg(NO₃)₂ solution is an effective approach for preparing high-strength α-HH with controlled morphology.

MEA aqueous solution is widely utilized as an absorbent in chemical absorption processes. However, it is challenged by many disadvantages, including low regeneration capacity and high energy consumption during regeneration. In this study, new no-aqueous MEA absorbents were prepared using alcohol ether organic solvents, including proprylene glycol monomethyl ether (PGME), ethylene glycol butyl ether (EGBE), poly (ethylene glycol) dimethyl ether (NHD) and diethylene glycol monoethyl Ether (DGME). Then the performance of the absorbents was assessed through a series of experiments and based on the results, a comparison was made between the non-aqueous absorbents to the conventional absorbent (30% (mass) MEA aqueous solution). It was found that the organic solvent system presented a higher CO₂ removal efficiency than the MEA-H₂O system in the first 350 s, with the maximum enhancement ranging from 5.16% to 14.36%. While NHD improved the CO₂ loading but reduced the regeneration efficiency. Except for the MEA-NHD system, all the other no-aqueous absorbents possessed a better regeneration efficiency than the MEA aqueous solution, which offers them the potential for industrial application. According to the data from NMR and FTIR analysis, after CO₂ absorption, the products in the MEA-EGBE and MEA-DGME systems were mainly found in the lower phase, the other phase was mainly organic solvents. Therefore, only the lower phase needs to be treated during desorption, with the upper phase being recycled directly, thus reducing energy consumption. The use of alcohol ether organic solvents can improve the CO₂ capture performance of absorbents to a certain extent and enhance their regeneration ability, providing a new direction for the subsequent research of non-aqueous absorbents.

With the energy problem becoming increasingly severe, industrial energy efficiency issues need to be solved urgently. The tube and shell heat exchanger, as the most widely used device for energy recovery and utilisation, its optimal design has become a significantly important research topic. Optimal design solves the tediousness of traditional design and can easily and accurately give the desired design results. Several industrial heat duty targets and pressure drop limitations for the design of shell-and-tube heat exchangers, such as high heat transfer efficiency, large temperature correction coefficient, and high capacity, cannot be met by single-shell units and require series or parallel arrangements. This paper uses Set Trimming to optimize the design of double shell and tube heat exchangers, assuming the possibility of series, parallel, or series-parallel arrangements. Minimum heat transfer area and minimum total annualized cost are used as objective functions to optimize the design of a single or double-shell heat exchanger that better meets the objectives.

The dispersibility of active components in hydrodesulfurization (HDS) catalysts significantly influences the corresponding catalytic performance. In this study, sugar-based materials (glucose, chitosan, soluble starch, and corn starch) were utilized to prepare CoMo bulk HDS catalysts through a sugar foaming process. The foaming intermediates were analyzed using TG, FTIR, and Raman techniques to investigate the pyrolysis and carbonization process, revealing the presence of graphitic carbon in the 3DPG, 3DPSS, and 3DPCS catalysts even after calcination in an air atmosphere. The catalysts were further characterized using SEM, XRD, TEM, low-temperature N₂ physical adsorption, and XPS. The 3DPSS catalyst exhibited a thiophene conversion of 94.8% at 360 ℃ and 1 MPa, which could be ascribed to its unique three-dimensional pore structure, high dispersion of MoS₂ (0.21), and high fraction of Mo⁴⁺ (83.14%). This study demonstrates the potential of using the sugar foaming technique to develop highly efficient HDS catalysts and provides new insights into the relationship between the physicochemical properties of the obtained catalysts and their catalytic performance.

The application of plant measurement data for system identification and model predictive control (MPC) has garnered significant interest. However, the pervasive presence of noise and contamination in industrial data often compromises data quality, thereby degrading performance and reliability of model. To address this challenge, this study proposes a nonlinear MPC method based on robust time delay particle filtering (RPF-MPC). This method is specifically designed to mitigate the impact of stochastic time delays and noise on both model learning and control. RPF-MPC utilizes robust particle filtering with a Laplace distribution to reliably estimate parameters and unknown time delays. In this way, the controller is able to efficiently handle noise and outliers even when the data deviates from a Gaussian distribution. The proposed algorithm is presented in detail, a nonlinear numerical case and a fuel cell water cooling control case are presented to validate the effectiveness of the RPF-MPC method. Simulation results validate the effectiveness and robustness of the RPF-MPC method in handling uncertainty and improving control performance in the PEMFC process.

The industrial-grade black mass of LiFePO₄/LiNi_xMn_yO₄/C from spent lithium-ion battery is difficult to be recovered because of its complex composition. In this study, a recycling of graphite and comprehensive recovery of valuable metals from industrial-grade black mass of spent lithium-ion battery was proposed. Acid leaching can separate graphite and cathode materials well. The separated graphite was purified by roasting, and its electrochemical properties were tested. The specific discharge capacity of graphite purified at 600° are the best, which reach 342.46 mA·h·g^-1 at 0.1 C. After 50 cycles at 0.1 C, the capacity retention rate was 98.26%. The charge-discharge cycle stability was improved at high rates. Nearly 100% of copper can be recovered from leaching solution by electrodeposition. FePO₄·2H₂O is recovered by adjusting the pH of the solution to 2, and α-FePO₄ is obtained by roasting. Ni, Mn and Li can be recovered by precipitation separation. The optimum conditions for the recovery process was determined, and the mechanisms of the leaching and electrodeposition process were characterized by XRD, XPS, SEM-EDS.

The current industrial-scale production of molybdenum-99 (⁹⁹Mo) and iodine-131 (¹³¹I) is heavily predicated on thermal neutron irradiation of LEU targets. In this route, ⁹⁹Mo and ¹³¹I are separated using a solid-phase extraction approach. The goal of this study was to develop and evaluate copolymeric beads that could be used to separate ⁹⁹Mo and ¹³¹I from their aqueous solutions. Different aminated styrene-divinyl benzene co-polymeric beads were successfully manufactured for this approach. The structural features of the synthesized copolymers were characterized. The resin frameworks were found to have homogeneous spherical shapes decorated with a very thin layer of amine moieties. The FT-IR peaks caused by N-H stretching and C-N bending vibrations show the successful functionalization of the resins' surfaces with amine moieties selective for the sorption of I^- over MoO₄^2- ions. Under various circumstances, the produced resins were assessed for sorption of ⁹⁹Mo and ¹³¹I from their aqueous solutions. They showed an enhanced sorption capability for I^- ions compared to MoO₄^2- ions and attained equilibrium in less than 20 min. Data declare that the sorption of MoO₄^2- and I^- ions onto synthesized resins was attained through an ion exchange process with Cl^- ions. In such interactions, one iodide ion (I^-) consumes only one active site from the resin surface, while two active sites must be exhausted to retain one MoO₄^2- ion onto the surface of the resins. The exchange interaction of both MoO₄^2- and I^- ions was an endothermic process. Further, the elution of ⁹⁹Mo and ¹³¹I radioisotopes loaded on synthesized resins was investigated using various eluents. Additional sets of individual and binary dynamic experiments were performed using columns packed with trimethylamine styrene divinyl benzene (TMA-PSDVB) and triethylamine styrene divinyl benzene (TEA-PSDVB) resins. The individual breakthrough sorption capacity of TMA-PSDVB and TEA-PSDVB resins had values of 381.6 and 352.6 mg·g^-1 for ¹³¹I and values of 134.7 and 117.2 mg·g^-1 for ⁹⁹Mo isotopes, respectively. Furthermore, TMA-PSDVB resin exhibited breakthrough sorption capacity for ⁹⁹Mo and ¹³¹I, in the binary system, amounting to 123.7 and 331.6 mg·g^-1 with elution percentages reaching 75.4% and 12.1%, respectively. These findings demonstrate that Mo(VI) ions were efficiently separated from I(I) ions. Finally, the reported aminated polymeric resins may be regarded as promising solid phases for the separation and recovery of Mo(VI) and I(I).

Thousands of radioactive mixed resins (MR) generated from nuclear industry can be processed by molten salt oxidation. There are three stages during the MSO process of MR: (1) the evaporation process (25-200 ℃); the thermal decomposition of the functional groups (200-450 ℃); (3) the depolymerization of styrene-divinylbenzene (450-800 ℃). Moreover, the thermal decomposition of the functional groups can be further divided into the thermal decomposition of the quaternary ammonium group (200-300 ℃) and the spitting off of the sulfonic acid group (300-450 ℃). NO and SO₂, respectively, were produced by the destruction of these functional groups. The carbonate salt can effectively adsorb NO and SO₂, whose contents decrease from 17.72% to 3.32% to 2.08% and 1.45%. Moreover, the sulfate contents in molten salt can be promoted by the generation of nitrate, which increase from 12.87% to 25.44% at 500 ℃. The change of the standard Gibbs free energy (ΔG_m^θ) of the reactions about the generations of nitrate and sulfur species, and the reactions between the nitrate and sulfur species were also proved by the calculation results of HSC chemistry 6.0. Both experimental and calculated results support the finding that the generation of nitrate from MR can catalyze the further oxidation of residue.

Composite materials are attracting considerable interest in water treatment due to their specific properties. Given these properties and the need to remove dyes from water, this work aims to develop an innovative composite material based on local clay (abundant and inexpensive), TiO₂ and CuO for wastewater treatment application. Although much work has been devoted to the design of clay-based composites, to our knowledge, no study has explored the use of Boula-Ibib clay decorated with TiO₂ and CuO to adsorb tartrazine (TTRZ) in aqueous solution. The CuO-TiO₂-clay composite was synthesized by incorporating TiO₂ and CuO on the clay surface using the sol-gel method. The crystalline properties, morphology and specific surface area of the composite were examined by X-ray diffraction, X-ray fluorescence, scanning electron microscopy and the Brunauer-Emmett-Teller method respectively. As results, the specific surface area of 85.23 m²·g^-1 was obtained for the CuO-TiO₂-clay which is higher than that of the raw clay (53.84 m²·g^-1). The results of adsorption studies showed a TTRZ uptake capacity of 16.08 mg·g^-1 after 30 min, with a concentration of 50 mg·L^-1, at pH 6.4 with the optimal composite mass of 0.01 g. Kinetic and isothermal studies showed that adsorption obeyed the pseudo-second-order model and the Radke-Prausnitz isotherm. Thermodynamic studies revealed that the adsorption of TTRZ by the composite is an exothermic, non-spontaneous process that leads to a reduction of disorder in the system. It was established that CuO-TiO₂-clay could be effectively reused over four cycles without damage of its structure which represent an economic advantage.

The gas transport properties of both single and mixed gas systems including CH₄, CO₂, N₂, C₂H₆, and helium (He) were investigated using novel polymer membranes fabricated via solution casting from organic solvents. The fluorinated polytriazole polymers were synthesized through a polycondensation method incorporating hexafluoroisopropylidene the main polymer backbone, with various fluorinated aniline derivatives as side chains. It was observed that the bulky fluorinated aniline derivative groups such as 4-fluoroaniline, 2,5-difluoroaniline, 4-bromo-2,5-difluoroaniline, and 2,3,4,5,6-pentafluoroaniline significantly influenced the gas separation performance of the polymer membranes, particularly in terms of permeability and selectivity. The membranes exhibited excellent mechanical stability across a wide range of pure CO₂ feed pressures (100-800 psi, 1 psi = 6.895 kPa) without signs of plasticization, highlighting their robustness for high-pressure applications. Additionally, the polymer synthesis process is reproducible and can be readily scaled, with each material displaying high solubility in organic solvents such as dimethyl acetamide, chloroform, and N-methyl pyrrolidone. Compared to gases such as CH₄, N₂, and C₂H₆, the newly developed polymer membranes demonstrated superior permeability for CO₂ and He under upstream feed pressures of up to 800 psi. These materials represent a completely novel class of polymer membranes tailored for advanced gas purification technologies. Their enhanced separation performance, particularly for CO₂ removal and He recovery from natural gas streams at high processing pressures, positions them as promising candidates for industrial applications in gas purification and separation.