Herein, the liquid-solid mass transfer characteristics in micropacked bed reactors (μPBRs) operated with immiscible liquid-liquid two-phase flow is experimentally investigated. It is found that the overall volumetric liquid-solid mass transfer coefficient (k_sa) increases with the total flow rate and the channel-to-particle diameter ratio, while decreases with the organic-to-aqueous phase flow rate ratio. A satisfactory correlation model for calculating k_sa of the liquid-liquid μPBRs is developed. The new knowledge obtained would be useful in guiding the design and optimization of the liquid-liquid μPBRs.

By enhancing surface interaction between metal oxide particles and carbon-based materials, it can effectively improve Faraday capacitance and conductivity, ultimately achieving high energy density with sufficient redox reactions in supercapacitors. Through a gentle biomineralization process and subsequent thermal reduction strategy, we successfully prepared the graphene oxide (GO) wrapping mixed-valence manganese oxides (MnO_x) and S, P self-codoped carbon matrix porous composite (MnO_x@SPC@reduced graphene oxide (RGO)). During the biomineralization process of engineered Pseudomonas sp. (M1) cells, GO nanosheets functioned as the ‘soil’ to adsorb Mn²⁺ ion and uniformly disperse biogenic Mn oxides (BMO). After undergoing annealing, the MnO_x nanoparticles were evenly wrapped with graphene, resulting in the creation of the MnO_x@SPC@RGO3 composite. This composite possesses strong C—O—Mn bond interfaces, numerous electroactive sites, and a uniform pore structure. By optimizing the synergistic interaction between the highly conductive graphene and the remarkable surface capacitance of MnO_x, the MnO_x@SPC@RGO3 electrode, with its intercalation Faraday reactions mechanism of Mn²⁺ ⇌ Mn³⁺ and Mn³⁺ ⇌ Mn⁴⁺ transformations, exhibits an outstanding specific capacity (448.3 F·g^-1 at 0.5 A·g^-1), multiplying performance (340.5 F·g^-1 at 10 A·g^-1), and cycling stability (93.8% retention after 5000 cycles). Moreover, the asymmetric all-solid-state supercapacitors of MnO_x@SPC@RGO3//PC exhibit an exceptional energy density of 64.8 W·h·kg^-1 and power density of 350 W·kg^-1, as well as a long lifespan with capacitance retention of 92.5% after 10000 cycles. In conclusion, the synthetic route utilizing biomineralization and thermal reduction exhibits significant potential for exploiting high-performance electrode materials in all-solid-state supercapacitor applications.

The direct oxidation of methane to methanol (DOMM) has been recognized as a significant technology for efficiently utilizing low-concentration coalbed methane (LCMM) and supplying liquid fuel. Herein, the noble metals (Pt, Pd and Ru) modified Cu/alkalized sepiolite (CuX/SEPA) catalysts were prepared and used for the DOMM in a gas-phase system at low temperatures. The CuRu/SEPA exhibited the highest methanol production of 53 μmol·g^-1·h^-1 and methanol selectivity of 90% under the optimal reaction conditions. Various characterizations demonstrated that the addition of Ru promoted the formation of Cu²⁺ and the contraction of Cu—Si/Al bonds to reduce the distance between framework Al atoms of SEPA to further generate more Al pairs, which facilitated the formation of reactive dicopper species ([Cu₂O]²⁺ or [Cu₂O₂]²⁺). Investigation of the reaction mechanism revealed that [Cu₂O]²⁺ or [Cu₂O₂]²⁺ species could adsorb and activate methane to form CH₃O* species and ultimately generated methanol with the assistance of water.

Accurately acquiring catalyst size and morphology is essential for supporting catalytic reaction process design and optimal control. We report an intelligent catalyst sizing and morphological classification method based on the Mask-RCNN framework. A dataset of 9880 high-resolution images was captured by using a self-made fiber-optic endoscopic system for 13 kinds of silicoaluminophosphate-34 (SAPO-34) catalyst samples with different coke. Then there were approximately 877881 individual particles extracted from this dataset by our AI-based particle recognition algorithm. To clearly describe the morphology of irregular particles, we proposed a hybrid classification criterion that combines five different parameters, which are deformity, circularity, roundness, aspect ratio, and compactness. Therefore, catalyst morphology can be classified into two categories with four types. The first category includes regular types, such as the spherical, ellipsoidal, and rod-shaped types. And all the irregular types fall into the second category. The experimental results showed that a catalyst particle tends to be larger when its coke deposition increased. Whereas particle morphology remained primarily spherical and ellipsoidal, the ratio of each type varied slightly according to its coke. Our findings illustrate that this is a promising approach to be developing intelligent instruments for catalyst particle sizing and classification.

In this work, several HZSM-5 catalysts with different Si/Al ratios treated with acids are selected as catalysts and used for hydration of cyclohexene to cyclohexanol. The results indicated that HZSM-5 (Si/Al = 38) modified with 4 mol·L^-1 nitric acid was selected as an efficient catalyst for improving the hydration efficiency of cyclohexene. Furthermore, the microstructures and properties of fresh, used and regenerated acid-modified catalysts have been characterized by X-ray diffraction, scanning electron microscopy, nitrogen adsorption/desorption isotherm, Fourier transform infrared, thermal gravimetric analyzer, ammonia temperature programmed desorption and pyridine adsorbs Fourier transform infrared. The characterization results indicated that the total surface areas and pore volume of HZSM-5 zeolite increased after nitric acid treatment due to the formation of mesoporous structure. This benefits the diffusion rate of reactants and products, which improves the hydration efficiency and stability of the catalyst. Under the catalysis of HZSM-5, the conversion of cyclohexene was found to be 9.0%. However, treatment of HZSM-5 with nitric acid enhanced the conversion of cyclohexene to 12.2%, achieving a selectivity of 99.7% for cyclohexanol under optimal reaction conditions. This work affords a mild and efficient approach for improving the hydration efficiency and has potential industrial application value.

Carbon-supported mercury catalysts are extensively employed in calcium carbide-based polyvinyl chloride (PVC) industries, but the usage of mercury-based catalysts can pose an environmental threat due to the release of mercury into the surrounding area during the operation period. In this study, a highly active and stable mercury-based catalyst was developed, utilizing the nitrogen atom of the support as the anchor site to enhance the interaction between active sites (HgCl₂) and the carbon support (N-AC). Thermal loss rate testing and thermogravimetric analysis results demonstrate that, compared to commercial activated carbon, N-doped carbon can effectively increase the heat stability of HgCl₂. The obtained mercury-based catalysts (HgCl₂/N-AC) exhibit significant catalytic performance, achieving 2.5 times the C₂H₂ conversion of conventional HgCl₂/AC catalysts. Experimental analysis combined with theoretical calculations reveals that, contrary to the Eley-Rideal (ER) mechanism of HgCl₂/AC, the HgCl₂/N-AC catalyst follows the Langmuir-Hinshelwood (LH) adsorption mechanism. The nitrogen sites and HgCl₂ on the catalyst enhance the adsorption capabilities of the HCl and C₂H₂, thereby improving the catalytic performance. Based on the modification of the active center by these solid ligands, the loading amount of HgCl₂ on the catalyst can be further reduced from the current 6.5% to 3%. Considering the absence of successful industrial applications for mercury-free catalysts, and based on the current annual consumption of commercial mercury chloride catalysts in the PVC industry, the widespread adoption of this technology could annually reduce the usage of chlorine mercury by 500 tons, making a notable contribution to mercury compliance, reduction, and emissions control in China. It also serves as a bridge between mercury-free and low-mercury catalysts. Moreover, this solid ligand technology can assist in the application research of mercury-free catalysts.

During the production of natural gas hydrates, micron-sized sand particles coexist with hydrate within the transportation pipeline, posing a significant threat to the safety of pipeline flow. However, the influence of sand particles on hydrate formation mechanisms and rheological properties remains poorly understood. Consequently, using a high-pressure reactor system, the phase equilibrium conditions, hydrate formation characteristics, hydrate concentration, and the slurry viscosity in micron-sized sand system are investigated in this work. Furthermore, the effects of sand particle size, sand concentration, and initial pressure on these properties are analyzed. The results indicate that a high concentration of micron-sized sand particles enhances the formation of methane hydrates. When the volume fraction of sand particles exceeds or equals 3%, the phase equilibrium conditions of the methane hydrate shift to the left relative to that of the pure water system(lower temperature, higher pressure). This shift becomes more pronounced with smaller particle sizes. Besides, under these sand concentration conditions, methane hydrates exhibit secondary or even multiple formation events, though the formation rate decreases. Additionally, the torque increases significantly and fluctuates considerably. The RoscoeBrinkman model yields the most accurate slurry viscosity calculations, and as sand concentration increases, both hydrate concentration and slurry viscosity also increase.

The multipath application of green resources needs to be realised under the carbon neutrality goal. Worldwide, biomass is a resource in urgent need of treatment. In this paper, corn stover biomass (YM) or biochar with different particle sizes (YMF or YMX) was added during the preparation of coal-water slurry to investigate its effect on the performance of coal-water slurry and the micro-mechanism. The results showed that the fixed viscosity concentration of coal-water slurry (CYWS) with YM was only 47.42%, and the flowability was 49.9 mm, which made the slurry performance poor. The fixed viscosity concentration of coal-water slurry (CFWS) blended with YMF and coal-water slurry (CXWS) blended with YMX increased by 10.41% and 14.24%, respectively, compared with CYWS. Meanwhile, CXWS had the lowest thixotropy and yield stress, with a yield stress of only 16.13 Pa, which was 77.31 Pa lower than that of CYWS. This indicates that YMX treated by charring and milling is more favorable to be blended with coal to prepare coal-water slurry. This is due to the enhanced hydrophilicity and electronegativity of YMX. The enhanced hydrophilicity reduces the tendency to form three-dimensional networks in coal-water slurry, while the enhanced electronegativity improves the electrostatic repulsion between particles, which is beneficial to the dispersion of particles. In the subsequent EDLVO analyses, the same idea was proved.

Hydrotreatment is a critical process in the petrochemical industry to produce gasoline or diesel. Proper kinetic models and accurate kinetic parameters of hydrotreatment reactions are important for the industrial reactor design and scale-up research. In this work, hydrogenation kinetics of alkene and aromatic model compounds were studied thoroughly to provide deep understanding on alkene and aromatic hydrogenation behaviors in gasoline and diesel hydrotreating. Commercial NiMo hydrotreatment catalysts were used to obtain experimental data of hydrogenation reactions. Cyclohexene, 1-octene, naphthalene and phenanthrene were used as model compounds of alkenes and aromatics. Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetic models for hydrotreatment reactions were established. In addition, phase equilibrium calculations were combined with kinetic study, and it is discovered that using calculated liquid phase compositions as kinetic model input could greatly enhance the accuracy of kinetic models and the quality of kinetic parameters, leading to higher accordance with experimental results. Using kinetic models and phase equilibrium analysis, the effect of reaction conditions (temperature, pressure, and H₂/oil ratio) on reaction rates were also predicted and clarified. The importance of phase equilibrium in kinetic analysis for hydrotreating reactions was demonstrated in this study, which provides an effective approach for future hydrotreatment reactor design and catalyst optimization.

Continuous-flow upgrading of pentaerythritol synthesis technology via base-catalyzed aldol and Cannizzaro reactions of formaldehyde and acetaldehyde faces the challenge of effectively controlling the critical side reaction of hydroxymethyl acetaldehyde (HA) to the acrolein intermediate. Here, we first identified the forms of industrial formaldehyde as methane diol that easily converts to the alkaline formaldehyde under alkaline (NaOH) environment. The carbonyl group of alkaline formaldehyde induces deprotonation of acetaldehyde instead of the recognized base-hydroxyl group-induced deprotonation, and it needs to overcome only 18.31 kcal·mol^-1 (1 kcal = 4.186 kJ) energy barrier to form key intermediates of HA. The sodium solvation cage formed by NaOH hexa-coordinated formaldehyde effectively inhibits the alkalinity, thus contributing to a high energy barrier (46.21 kcal·mol^-1) to unwanted acrolein formation. In addition, the solvation cage gradually opens to increase the alkalinity with the consumption of formaldehyde, thus facilitating the subsequent Cannizzaro reaction (to overcome 11.77 kcal·mol^-1). In comparison, strong alkalinity promotes the formation of acrolein (36.65 kcal·mol^-1) to initiate the acetal side reaction, while weak alkalinity reduces the possibility of the Cannizzaro reaction (to overcome 20.44 kcal·mol^-1). This theoretically reveals the importance of the segmented feeding of weak and strong bases to successively control the aldol reaction and Cannizzaro reaction, and the combination of Na₂CO₃ or HCOONa with NaOH improves the pentaerythritol yield by 7% to 13% compared to that of NaOH alone (70% yield) within 1 min at a throughput of 155.7 ml·min^-1.

The exosomes hold significant potential in disease diagnosis and therapeutic interventions. The objective of this study was to investigate the potential of aqueous two-phase systems (ATPSs) for the separation of bovine milk exosomes. The milk exosome partition behaviors and bovine milk separation were investigated, and the ATPSs and bovine milk whey addition was optimized. The optimal separation conditions were identified as 16% (mass) polyethylene glycol 4000, 10% (mass) dipotassium phosphate, and 1% (mass) enzymatic hydrolysis bovine milk whey. During the separation process, bovine milk exosomes were predominantly enriched in the interphase, while protein impurities were primarily found in the bottom phase. The process yielded bovine milk exosomes of 2.0 × 10¹¹ particles per ml whey with high purity (staining rate>90%, 7.01 × 10¹⁰ particles per mg protein) and high uniformity (polydispersity index <0.03). The isolated exosomes were characterized and identified by transmission electron microscopy, zeta potential and size distribution. The results demonstrated aqueous two-phase extraction possesses a robust capability for the enrichment and separation of exosomes directly from bovine milk whey, presenting a novel approach for the large-scale isolation of exosomes.

Heteroatom-doped porous carbon materials have been widely studied due to their high specific surface area and high heteroatom content, but it is difficult to achieve high specific surface area and high heteroatom content at the same time. Herein, a simple method is introduced to prepare N/O co-doped hierarchical porous carbon materials (DNZKs). Phthalonitrile resins (DNZs) were prepared by using 1,3-bis(3,4-dicyanophenoxy)benzene as raw material and ZnCl₂/urea as composite curing agent, and then using KOH as activator to successfully prepare DNZKs with high specific surface area, developed pores and high N/O content. The porous carbon material (DNZK@400) obtained at a curing temperature of 400 ℃ has the highest N content (4.97% (mass)), a large specific surface area (2026 m²·g^-1), a high micropore proportion (0.9), a high O content (7.53% (mass)), and the best specific capacitance (up to 567 F·g^-1 at 0.1 A·g^-1), which can be attribute to the high temperature resistance of the nitrogen-containing aromatic heterocyclic structure in DNZs. When the mass ratio of resin and KOH is 1:1, the specific capacitance of the sample tested by the acid three-electrode system is obtained, and it is found that the material has high cycling stability (119% specific capacitance retention after 100,000 cycle tests). This work proposes a simple and easy-to-operate method for the preparation of multifunctional porous carbon.

In current spent nuclear fuel reprocessing, the predominant method involves chemical extraction, leveraging the differing distribution ratios of elements to achieve separation and purification. Effective separation of uranium (U), plutonium (Pu), and neptunium (Np) typically relies on redox processes that alter their oxidation states during extraction. Therefore, reductants play a critical role in reprocessing processes. An important shift in the advanced reprocessing process is the use of salt-free reagents in the actinide separation process. In addition, the salt content in the reprocessing stream is often indicative of the overall technological sophistication of the process, and it is critical to reform the reductants used in the main process stream. Salt-free reductants have attracted much attention in recent years for basic and applied research in reprocessing processes because of their advantages such as being easily destroyed, not introducing salts, reacting quickly, simplifying the process, and reducing the amount of waste. This study summarizes emerging salt-free reagents with potential applications in reprocessing, and outlines their kinetic and chemical reaction mechanism properties in reducing Pu(IV) and Np(VI). The conclusion discusses the future potential of salt-free reagents in reprocessing. This study summarizes the currently well-studied salt-free reductants and offers recommendations and future research directions in salt-free alternatives.

Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work. It was found that after the growth of the hydrate film at the interface, further growth of hydrate due to the suction of water in the capillary system formed between the wall of the cuvette and the end boundary of the hydrate layer occurs. Most probably, substantial effects on the formation of this capillary system may be caused by variations in reactor wall properties, for example, hydrophobic-hydrophilic balance, roughness, etc. We found, that the rate of CO₂ hydrate film growth on the surface of the humic acid aqueous solution is 4-fold to lower in comparison with the growth rate on the surface of pure water. We suppose that this is caused by the adsorption of humic acid associates on the surface of hydrate particles and, as a consequence, by the deceleration of the diffusion of dissolved carbon dioxide to the growing hydrate particle.

One of the main challenges in oil-water separation of traditional Chinese medicines (TCM) is to obtain essential oils from the aromatic water of TCM. In this study, silicon dioxide/polyvinylidene fluoride (SiO₂/PVDF) membranes were prepared using nonsolvent induce phase separation. Then polydimethylsiloxane (PDMS) was coated to obtain PDMS/SiO₂/PVDF membranes. Separated essential oils and water from aromatic water in the gaseous state by vapor permeation membrane separation technology. The relationship between membrane structure and membrane separation effect was investigated. Response surface methodology was used to develop a quadratic model for the separation factor, membrane permeation separation index and membrane preparation process. The optimal process parameters for the membrane separation were 12.31% (mass) concentration of PVDF solution, 9.6% (mass) of N,N-dimethylacetamide in the solidification bath, and 0.2 g hydrophobic nano-SiO₂ incorporation, with a separation factor of 14.45, and a membrane flux of 1203.04 g·m^-2·h^-1. Compared with the PDMS/PVDF membranes, the separation factor and membrane flux were increased by 68.59% and 3.46%, respectively. Compared with the SiO₂/PVDF membranes, the separation factor and membrane flux were increased by 478% and 79.33%, respectively. Effectively mitigated the limitations of traditional polymer membrane material performance affected by the “trade-off” effect. Attenuated total internal reflection-Fourier transform infrared spectroscopy, contact angle, scanning electron microscopy and energy dispersive spectroscopy were used to characterize the PDMS/SiO₂/PVDF membranes, and gas chromatography was used to characterize the permeate. In addition, the contents of L-menthol, L-menthone, menthyl acetate and limonene in the permeate, conformed to the European Pharmacopoeia standards. This study provided an effective preparation strategy of a feasible hydrophobic powder polymer membrane for the separation of essential oils from gaseous peppermint aromatic water.

The fabrication of monolithic ZSM-5 catalysts via extrusion is pivotal for industrial catalytic processes; nevertheless, the addition of adhesives might affect their catalytic performance. Herein, the rice husk-derived bio-SiO₂, serving as a silicon source and natural adhesive, was introduced in the synthesis and extrusion of ZSM-5 catalysts denoted as BioZSM-5, thereby enhancing their industrial viability and catalytic performance. The f-n-BioZSM-5 (obtained by extrusion of n-BioZSM-5) showcased enhanced butene and pentene selectivity, exhibiting robust stability, achieving an impressive 84.8% olefin selectivity (over 10 cycles). The biomass template significantly improved porosity, acidity, and anti-coking properties. Moreover, the f-n-BioZSM-5 exhibited a compressive strength 4.3 times superior to that of f-n-ZSM-5 without using bio-template, achieving better abrasion resistance and enhanced mechanical properties even using 1/3 of the adhesive dosage. These results will provide valuable guidance for developing shaped zeolite catalysts for industrial catalytic pyrolysis applications, especially for the production of olefin from fatty acids.

Accurate prediction of solubility data in the Sodium Chloride-Sodium Sulfate-Water system is essential. It provides theoretical support for salt lake resource development and wastewater treatment technologies. This study proposes an innovative solubility prediction approach. It addresses the limitations of traditional thermodynamic models. This is particularly important when experimental data from various sources contain inconsistencies. Our approach combines the Weighted Local Outlier Factor technique for anomaly detection with a Deep Ensemble Neural Network architecture. This methodology effectively removes local outliers while preserving data distribution integrity, and integrates multiple neural network sub-models to comprehensively capture system features while minimizing individual model biases. Experimental validation demonstrates exceptional prediction performance across temperatures from -20 °C to 150 °C, achieving a coefficient of determination of 0.989 after Bayesian hyperparameter optimization. This data-driven approach provides more accurate and universally applicable solubility predictions than conventional thermodynamic models, offering theoretical guidance for industrial applications in salt lake resource utilization, separation process optimization, and environmental salt management systems.

The optimization of reaction processes is crucial for the green, efficient, and sustainable development of the chemical industry. However, how to address the problems posed by multiple variables, nonlinearities, and uncertainties during optimization remains a formidable challenge. In this study, a strategy combining interpretable machine learning with metaheuristic optimization algorithms is employed to optimize the reaction process. First, experimental data from a biodiesel production process are collected to establish a database. These data are then used to construct a predictive model based on artificial neural network (ANN) models. Subsequently, interpretable machine learning techniques are applied for quantitative analysis and verification of the model. Finally, four metaheuristic optimization algorithms are coupled with the ANN model to achieve the desired optimization. The research results show that the methanol: palm fatty acid distillate (PFAD) molar ratio contributes the most to the reaction outcome, accounting for 41%. The ANN-simulated annealing (SA) hybrid method is more suitable for this optimization, and the optimal process parameters are a catalyst concentration of 3.00% (mass), a methanol: PFAD molar ratio of 8.67, and a reaction time of 30 min. This study provides deeper insights into reaction process optimization, which will facilitate future applications in various reaction optimization processes.

Metal-organic frameworks (MOFs), with their ultrahigh specific surface area, uniformly distributed pores, and tunable structures, are promising candidates for next-generation active electrode materials in lithium-ion batteries (LIBs). However, their application is hindered by poor cycling stability due to structural collapse during charge-discharge cycles. To address this issue, we developed an alloy and multi-solvent thermal method strategy to synthesize Co/Zn bimetallic MOFs based on Naphthalenetetracarboxylic acid (NTCA). The resulting petal-like Co/Zn-NTCA MOF demonstrates outstanding electrochemical performance. The incorporation of zinc ions not only significantly enhances cycling stability but also markedly increases the specific capacity of the anode material. At a current density of 200 mA·g^-1, the Co/Zn (2:1)-NTCA MOF demonstrated an impressive reversible capacity of 956 mA·h·g^-1 after 150 cycles. Even after 500 cycles, the specific capacity of the electrode remained high, with a value of 438 mA·h·g^-1 at a current density of 1000 A·g^-1.

In observation of efficiently utilizing the boil off gas (BOG) from onboard liquefied natural gas (LNG), storage by adsorption is employed to construct an auxiliary system for fuel storage. A typical LNG powered ship was selected, and the storage by adsorption system was designed as per the amount of BOG released during the process of charging and that from daily evaporation on the LNG storage tank. Researches were conducted experimentally and numerically on a 1 L conformable vessel typically designed for adsorbing BOG. Verification of the accuracy of the results from simulations was performed by comparing the data recorded during the charging and discharging process of methane on the vessel packed with one kind of commercially available activated carbon SAC-01 (S_BET = 1507 m²·g^-1). Simulations were conducted further to evaluate the performance of the vessel respectively filled with activated carbon AX-21, HKUST-1, MIL-101(Cr), MOF-5. It shows that the mean relative error between the data from simulations and the experimental data is less than 5%. Results also reveal that, within the flow rates range in correspondence with the fuel consumed by the model ship's power unit under its typical working conditions, the mean temperature fluctuation within the vessel is the weakest while packing HKUST-1, which results in the largest accumulated amount of discharge. It suggests that HKUST-1 is a suitable adsorbent for storage by adsorption of BOG from on board LNG.