The hydrogenation process in oil fields is a crucial step for improving oil quality and reducing pollutant emissions during crude oil processing.In the context of"dual carbon",the greenization of hydrogen supply mode has become a key factor in industry transformation.The traditional hydrogen production mode has a higher carbon emission intensity and is seriously out of sync with the low-carbon development requirements of the oil and gas industry.Therefore,it is of greater practical significance to develop green and safe hydrogen production methods.This paper uses a mixture of(NH4)2S2O8 and dicyandiamide as the precursor and prepares porous g-C3N4(pg-C3N4)through a thermal polymerization method.The microstructure,light absorption capacity,chemical structure,and crystal structure of pg-C3N4 are analyzed by TEM,XRD,DRS,and FT-IR spectroscopy.The photocatalysis hydrogen production from water splitting and the degradation of pollutants over pg-C3N4 are also investigated.The results show that the specific surface area of pg-C3N4 is approximately 49 m2/g.The results show that the specific surface area of pg-C₃N₄ is approximately 49 m²/g.Compared with bulk g-C₃N₄,pg-C₃N₄ possesses a larger specific surface area and a relatively higher separation efficiency of photogenerated electron-hole pairs,thereby significantly enhancing its performance in water splitting for hydrogen production under visible light as well as its activity in decomposing Rhodamine B(RhB).Moreover,it can maintain good performance and structural stability.This paper provides a green hydrogen production method for the development of hydrogenation processes in oil fields.
The industrialization of all-vanadium flow batteries（VFB） is currently hindered by the inherent trade-off between proton conductivity and vanadium ion rejection in ion exchange membrane materials.To address this challenge,a novel membrane architecture was innovatively proposed by constructing a composite membrane loaded with S-SN nanosheets.The performance of the composite membrane was systematically evaluated through micro-morphology characterization,physicochemical analyses including proton conduction and mechanical strength,as well as battery polarization behavior and constant-current discharge stability tests.The results demonstrate that the prepared composite membrane achieves a coulombic efficiency of 96.4% and an energy efficiency of 76.81% at a high current density of 200 mA/cm2.After 500 cycles,the membrane exhibits excellent cycling stability with a capacity retention of 74.91%.By precisely regulating the membrane structure, this innovative design successfully resolves the balance dilemma of ion-selective transport,providing a new strategy for developing cost-effective and stable energy storage membranes.
In the development process of Block G in Dagang Oilfield, the air foam flooding system exhibits favorable oil displacement performance. However, affected by factors such as foam preparation technology, gas injection volume, gas injection rate and reservoir permeability heterogeneity, gas channeling is prone to occur during oil and gas production. To explore the mechanism of gas channeling in oil reservoirs and its impacts on oil and gas field development, experiments on the oil displacement performance of air foam flooding were conducted using a Brookfield viscometer, gas chromatograph and core flooding apparatus. The experiments investigated the effects of profile control agent types, gas injection modes and reservoir heterogeneity. Corresponding effective technologies for gas channeling control were also proposed. The results show that in the air foam flooding test with heterogeneous models, foam preferentially enters high-permeability layers, which increases seepage resistance and reduces water absorption index, thus achieving excellent effects of water control and oil production enhancement. Compared with conventional air foam flooding, the injection of Cr3+ polymer gel and hydrophobic associating polymer can effectively restrain gas channeling, and further improve the oil-increasing and water-reducing performance of air foam flooding. When the injection volume of gel plugging agent is 0.20 PV, the maximum increment of oil recovery factor reaches 15.23%; when the injection volume of polymer is 0.30 PV, the maximum increment of oil recovery factor is 11.35%.
The narrow strip-shaped reservoirs in the lower member of Minghuazhen Formation in the Bonan area of the Bohai Bay Basin are characterized by diverse types of dominant flow channels,which are difficult to identify and control,severely impairing the waterflooding development effect.Based on the morphological characteristics of production curves from 112 tracer test samples,dominant flow channels were classified into four levels.By investigating the reservoir physical property parameters and production dynamic response characteristics of each level,an innovative discrimination parameter system for dominant flow channels was established,and the development degree of preferential channels was quantitatively characterized.Using a combination of statistical methods and grey relational analysis,the main controlling factors affecting dominant flow channels were quantitatively determined,and classified control countermeasures for the four levels of preferential channels were proposed.The results show that after long-term water injection development,Level Ⅲ dominant flow channels accounts for the highest proportion,reaching 59%of the total.The average interpreted permeability is 7 037 mD,and the average radius of pore roar is 16.0 µm.The main factors affecting dominant flow channels are production pressure difference and channel width,which should be carefully considered in the design and dynamic adjustment of injection-production well spacing.The research findings provide a scientific basis for formulating water control measures and conducting full-cycle optimization and evaluation of profile control and profile modification and flooding in narrow strip-shaped reservoirs.Field applications have achieved favorable effects of water cut reduction and oil production increase.
Covalent organic frameworks (COFs) are a class of crystalline porous polymers formed by linking several light elements through covalent bonds. They feature large specific surface area, excellent chemical stability, and precisely tunable pore architecture, rendering them highly promising for adsorption applications. In this work, COF-TpPa-1 demonstrated effective performance as an adsorbent for the removal of two representative organic dyes (methyl green and congo red) from aqueous solutions. Comprehensive investigations were performed to analyze the effects of various factors while examining adsorption isotherms, kinetics, and thermodynamics. The results demonstrated that the adsorption of both methyl green and congo red onto COF-TpPa-1 followed the Langmuir isothermal adsorption model, indicating a predominant monolayer adsorption mechanism.Kinetic studies showed excellent accordance with the pseudo-second-order model, indicating chemisorption as the primary adsorption mechanism. The adsorption processes of COF-TpPa-1 for both dyes were endothermic and thermodynamically spontaneous.Remarkable maximum adsorption capacities of 253.17 mg/g for methyl green and 166.39 mg/g for congo red were achieved at 313 K. Furthermore, ethanol treatment enabled efficient dye desorption and adsorbent regeneration.
Conventional polymers fail to meet the requirements for channeling control and plugging under high temperature and high salinity conditions, creating an urgent demand for more durable materials.Two acrylamide-based preformed particle gels (PPGs): polyelectrolyte-based (DJZ-1) and polyzwitterionic-type (LXLZ-2) were synthesized for enhancing CO2 plugging efficiency. The swelling behavior of the gel was analyzed under different temperature, salinity and pH conditions using Ritger-Peppas and Yavari-Azizian models. The results indicate that the swelling degrees of DJZ-1 and LXLZ-2 in water are 56 and 18 respectively. With the rise of ionic strength, the swelling degree of DJZ-1 declines remarkably, whereas that of LXLZ-2 stays nearly constant. Changes in pH value only elevate the swelling degree of DJZ-1 and have no impact on LXLZ-2. LXLZ-1 can maintain long-term thermal stability under reservoir conditions at 120 ℃, and both systems can effectively exert the performance of PPG weak gel systems.
After the commissioning of gas storage facilities in edge-bottom water gas reservoirs, issues such as insufficient storage capacity and reduced peak shaving capacity often arise. In response to the differentiated vertical water invasion distribution and complex fault characteristics in block M, a differentiated water energy modeling method was adopted to simulate the impact of 3.2 to 14.0 times of water energy on the operation of the gas storage. The static evaluation of fault SGR was combined with dynamic failure prediction pressure, and the safe operation pressure of the gas storage was designed based on the "short board effect". Various well patterns were simulated and compared. Ultimately, a composite well pattern featuring "horizontal wells as the mainstay and vertical wells as a supplement" was adopted, with the deployment of 22 injection-production wells. A water control strategy of "low-speed slow injection at high structural positions" was implemented, leveraging the well pattern dominated by horizontal wells to enhance injection-production efficiency. The daily gas injection capacity of a single well reached 340 000 cubic meters, which is 2.1 times that of a vertical well. Practice has confirmed the feasibility of constructing gas storage facilities in edge-bottom water gas reservoirs, and this study provides important reference value for the optimal design of similar gas storage facilities.
Aqueous zinc-ion batteries (AZIBs) exhibit tremendous application potential in cutting-edge interdisciplinary fields such as wearable devices and biomedicine owing to their high safety, low cost, excellent electrochemical performance, and good biocompatibility. This paper provides a systematic review of structural-engineering strategies and recent advances in their gel electrolytes, with particular emphasis on the integrated optimization of ionic conduction, biocompatibility, mechanical properties, and interfacial stability of hydrogel and polymer electrolytes guided by molecular engineering and interfacial regulation. Furthermore, the development potential and evolution trends of hydrogel electrolytes in flexible integration and biomedical applications are discussed. This research provides novel ideas for the design and expanded application of high-performance hydrogel electrolytes.
A large amount of boil-off gas (BOG) is generated during the storage and transportation of liquefied natural gas,which results in not only resource wastage but also potential safety hazards.Therefore,the liquefied natural gas-adsorbed natural gas (LNG-ANG) coupling technology has attracted increasing attention from researchers.Developing efficient and stable adsorbents is the core key to the practical application of this technology.In view of the requirements of LNG-ANG coupling technology for adsorbents, this paper summarizes the research progress of metal-organic framework materials (MOFs) in methane adsorption at low temperature (about 159 K).By comparing the advantages and limitations of adsorption at low temperatures (159 K) with at room temperature (298 K),several MOFs materials that are more conducive to the adsorption and storage of methane are listed,including flexible MOFs,highly porous MOFs,hierarchically porous MOFs and MOF composites,aiming to offer references and guidance for the practical industrial application of MOFs in LNG-ANG coupling technology.
The conversion of CO2 to dimethyl carbonate(DMC)represents a promising route for sustainable synthesis and carbon resource utilization.In this study,a series of Zr-doped CeO2 catalysts derived from metal-organic frameworks(MOFs)via hydrothermal synthesis were applied to the direct synthesis of DMC from CO2 and CH3OH.The effects of varying Zr doping levels(molar fraction,the same below)on catalytic performance were systematically investigated,and the optimal Zr doping amount was determined.The catalysts were characterized using X-ray diffraction,high-resolution transmission electron microscopy,N2 adsorption-desorption,and X-ray photoelectron spectroscopy to elucidate their crystal phase,morphology,surface chemical states,and correlations between these properties and catalytic activity.Using the Zr/CeO2 catalyst with a 2%Zr doping level,the optimal process conditions for DMC synthesis from CO2 and CH3OH were investigated.The results indicate that under the conditions of 140 ℃,an initial CO2 pressure of 3 MPa,and a reaction time of 2 hours,the Zr/CeO2 catalyst with a 2%Zr doping content exhibits the highest CH3OH conversion rate and DMC production.
Nylon 66(PA66),as an important engineering plastic,features excellent mechanical properties,wear resistance and heat resistance,and is widely used in the automotive,electronic,mechanical and aerospace fields.However,its inherent high hygroscopicity,poor low-temperature toughness,insufficient processing fluidity and inadequate flame retardancy limit its application in some high-performance scenarios.In recent years,significant progress has been made in the modification research of PA66.Mainly through various means such as physical blending,chemical grafting, and copolymerization modification,its microstructure and macroscopic properties are regulated,thereby preparing composite materials with high strength,high toughness, low water absorption rate,excellent flame retardancy or thermal conductivity.This article introduces the research progress of various high-performance PA66 composites in recent years,analyzes the influence of various modification strategies on the structure and performance of the materials,and the preparation of various high-performance PA66 composites has expanded the application scope of PA66,which is more conducive to its development in high-performance and functional industries such as new energy and automobiles.
Against the backdrop of rising global energy needs and pressing environmental concerns,the advancement of efficient and sustainable green energy technologies is paramount.Zinc-air batteries(ZABs)present a highly promising solution,offering a high theoretical energy density and zero-carbon emissions.However,their widespread adoption is limited by the sluggish kinetics of the oxygen reduction reaction(ORR)at the air cathode and the inherent high cost and poor stability of precious-metal catalysts.Herein,we innovatively prepared a NH2-MXene/FePc composite catalyst by anchoring iron phthalocyanine(FePc)onto amino-functionalized MXene(NH2-MXene)as the support.The influence of the 3-aminopropyltriethoxysilane(APTES)addition amount on the catalyst's structure and ORR performance was systematically studied.The optimized NH2-MXene/FePc-100 catalyst demonstrates exceptional ORR activity,characterized by a high half-wave potential of 0.92 V,a low Tafel slope of 65.94 mV/dec,and a dominant four-electron transfer pathway.Notably,it exhibits outstanding stability,showing a minimal E1/2 degradation of only 20 mV after 5 000 cycles of accelerated durability test cycles.Moreover,ZABs equipped with this catalyst achieve superior performance,delivering a peak power density of 182.3 mW/cm2 and a specific capacity of 774.7 mA·h/g which significantly surpasses that of commercial Pt/C-based devices.
The dual-carbon strategy highlights the urgent need to develop efficient photocatalytic hydrogen production technologies.Graphitic carbon nitride(g-C3N4)has attracted wide attention due to its low cost and excellent stability,but it suffers from insufficient visible light absorption and rapid carrier recombination,which severely restricts its hydrogen production performance.To overcome these issues,we successfully prepared boron-doped g-C3N4(BCN)using a H3BO3-assisted segmented temperature-controlled calcination strategy,with boric acid as the boron source precursor.The effects of boron doping on the band structure and photoelectric properties of g-C3N4 were systematically investigated through various photoelectric characterization techniques.The results demonstrate that an appropriate level of boron doping effectively modulates the electronic structure of g-C3N4,enhancing its visible light absorption and improving the separation efficiency of photogenerated carriers.Specifically,the BCN-2:5 sample(with a mass ratio of H3BO3 to g-C3N4 of 2:5)achieves a hydrogen evolution rate of up to 1 507 μmol/(g·h)under visible light irradiation.This study offers valuable insights and guidance for the design of highly efficient doped g-C3N4 photocatalysts.
In the domain of chemical separation,the pursuit of straightforward and expeditious treatment of multicomponent industrial wastewater has emerged as a prominent trend.However,traditional methods have demonstrated low separation efficiency when dealing with emulsified phosphorus-containing wastewater.In this study,a cellulose membrane was used as the base matrix,and La(OH)3 nanoparticles were in-situ grown on it to construct a composite membrane capable of simultaneous phosphorus removal and demulsification.Structural characterization revealed that La(OH)3 was uniformly anchored on the fiber surface.The membrane's underwater superoleophobicity and low oil adhesion enabled it to separate various oil-in-water emulsions with an efficiency of 99.2％and a separation flux of 1 210 L/(m2•h).The membrane exhibited sustained high phosphorus removal and demulsification performance even after ten cycles,providing a scalable and sustainable new approach for the next generation of multicomponent industrial wastewater treatment.
Gold nanoparticles(Au NPs)exhibit great application potential in the reduction of aromatic nitro compound pollutants,owing to their nanoscale size effects and excellent catalytic properties.However,their tendency to aggregate has hindered practical applications.In this study,perfusion silica gel microspheres(PSM)with a hierarchical porous structure comprising macropores,mesopores,and perfusion pores were used as a support material.The surface of the PSM was first modified with thiol groups and then combined with gold nanoparticles to fabricate Au NPs/PSM composite microspheres.These composite microspheres were characterized by SEM,TEM,Raman spectroscopy and XRD.The catalytic performance of the Au NPs/PSM catalyst in reducing 4-nitrophenol to 4-aminophenol was investigated.The results showed that the composite microspheres retained their perfusion channels,and the Au NPs were uniformly distributed on the PSM surface.The average size of the Au NPs was approximately 4.8 nm,with a mass loading fraction of 2.72%.The Au NPs/PSM composite was employed as a catalyst for the reduction of 4-nitrophenol to 4-aminophenol.At 30 ℃,the catalytic reaction followed first-order kinetics,with a rate constant of 0.103 min-1.The composite microspheres demonstrate excellent catalytic activity,good stability,and high recyclability.
Electrocatalytic hydrogen evolution technology plays a pivotal role in promoting sustainable energy conversion and storage,which is essential for achieving carbon neutrality and enhancing the efficient utilization of renewable energy.However, current electrocatalysts still face significant challenges in terms of activity,stability,and cost,which hinder their large-scale application.Alloy catalysts,with their tunable compositions and structures as well as unique electronic properties,have demonstrated great potential in improving catalytic performance.This review provides a comprehensive overview of the performance modulation mechanisms and strategies of alloy catalysts in hydrogen evolution reactions.Specifically,it focuses on three key aspects:Composition design,crystal structure regulation,and hybridization with other functional materials,highlighting their recent advances in the electrocatalytic hydrogen evolution reaction.Representative studies are discussed to elucidate the synergistic effects among multiple metal components in alloy systems and their impact on catalytic performance.Finally,current challenges in rational alloy catalyst design are summarized,and future research directions are proposed,aiming to provide theoretical guidance and technical insights for the development of efficient and cost-effective electrocatalytic materials.
The current commercial Pd-based catalysts are expensive,so there is a need to develop alternative low-cost metal catalysts.In this study,hierarchical porous copper-based catalysts were synthesized via selective etching by adjusting alkali concentration,and were characterized using techniques including XRD,SEM,BET,MIP,and N2O chemisorption.The hydrogenation performance of the hierarchical porous Cu-based catalyst was evaluated under conditions of GHSV 30 000 h-1 and V(H2)/V(C3H6)/V(C4H6)/V(He)=137:98:1:196.Results indicate that the Cu-based catalyst possesses a hierarchical pore structure comprising macropores(4～5 μm)and mesopores(2～25 nm).The full conversion temperature of the hierarchical porous Cu-based catalyst is as low as 105 ℃,significantly lower than that of commercial Cu powder(220 ℃),while demonstrating stability exceeding 180 hours.The introduction of the hierarchical pore structure increases the active surface area of the catalyst and enhances the number of Cu active sites.Moreover,retaining an appropriate amount of Al species helps maintain the hierarchical pore structure and improves the resistance of Cu active sites to deactivation.
The consumption of fossil fuels has led to a series of environmental issues due to CO2 emissions,drawing increasing attention to carbon capture and storage(CCS)technology.Lithium silicate(Li4SiO4)is considered a highly promising sorbents due to its high CO2 capture capacity,low regeneration temperature,and good thermal stability.However,its widespread application is limited by the high cost of silicon sources and insufficient cycling performance.Low-cost fly ash was used as silicon source to synthesize Li4SiO4 via solid-state and impregnation-precipitation methods,followed by modification with K2CO3 doping.The materials were characterized by testing methods such as XRF,XRD,and SEM.The results show that the sorbents prepared by the solid-phase method at 700 ℃(LS-700)possesses a rich pore structure and a high specific surface area of 1.584 2 m2/g,and exhibits the optimal sorption performance,with the CO2 sorption capacity remaining at 0.179 7 g/g after 10 cycles.After K2CO3 doping,the CO2 sorption rate increased to 0.054 5 g/(g·min),which is 1.4 times that of the undoped sample.Mechanistic studies revealed that the formation of a low-temperature eutectic layer between K2CO3 and Li2CO3 promoted CO2 diffusion and reduced the reaction activation energy.This study provides an effective strategy for developing low-cost and high-performance Li4SiO4-based sorbents,demonstrating significant value for enhancing CO2 capture efficiency from coal-fired flue gas.
To address the issues of low theoretical specific capacity,poor fast-charging performance,and insufficient safety in commercial graphite anode materials,a new type of self-supporting composite electrode was constructed,which achieved an improvement in the comprehensive electrochemical performance of lithium-ion batteries.Using carbon cloth(CC)as a flexible substrate,a Co3O4/ZnO heterojunction structure was grown in situ on its surface via the hydrothermal method,followed by heat treatment,successfully preparing a self-supporting Co3O4@ZnO//CC anode material.Microstructural and compositional analyses were conducted using characterization techniques such as XRD,SEM,TEM,and XPS,while electrochemical tests were employed to evaluate its lithium storage performance.Results demonstrated that the three-dimensional porous nanosheet array of Co3O4@ZnO effectively mitigates volume changes and facilitates electron transport.The Co3O4@ZnO//CC electrode exhibited an initial discharge and charge specific capacity of 3.96 and 3.28 mA·h/cm2 at 2.00 mA/cm2 current density,respectively,with a coulombic efficiency of 82.83％ in the first cycle and a capacity retention rate of 56.40％after 100 cycles.Both its cycling stability and rate performance outperformed those of Co3O4//CC and ZnO//CC electrodes.
Currently,many methods for calculating oil saturation primarily rely on static methods,which are mainly used to calculate initial oil saturation and are not suitable for calculating dynamic oil saturation during the development process.To address the limitations of existing dynamic calculation methods,a general relationship between the oil-water relative permeability ratio and water saturation was derived based on the general formula for oil-water relative permeability.Through the In(1+x)series expansion,a trinomial formula was obtained,which enables full-range fitting of the oil-water relative permeability ratio and facilitates engineering application,overcoming the drawback that previous linear formulas could only fit the middle range.By establishing the relationship between the oil-water relative permeability ratio and water cut through water cut definition and radial flow formulas,we further develop a cubic polynomial function relationship between water saturation and water cut.When the water cut of a block,single well,or single layer is known,this relationship can be used to calculate water saturation at different development stages,and then oil saturation can be derived.The research method can provide a basis for the deployment of encryption well position,fine water injection and other adjustment measures.
