To study the structural variation of coke on residue HDCCR catalysts with time-on-stream, the spent catalysts tested at different times on a bench-scale continuous stirred tank reactor were analyzed. The spent catalysts were successively dissolved in steps with n-heptane and toluene to obtain toluene-soluble soft coke and hard coke deposited on catalysts. Then the structures of the two types of coke were analyzed respectively. The variation of sulfur content and carbon residue of hydrotreatedresidue was investigated, and it was concluded that the catalytic performance tended to decrease as the reaction proceeded. TG-MS, 13CNMR and Raman spectroscopywere used to investigate the structural changes of hard coke, it revealed that the aromaticity and graphitization of the hard coke did not significantly increase at the time-on-stream from 0 to 60 min. However, when the time-on-stream was increased to 240 min, the proportion of aromatic carbon in the hard coke increased, and the graphitization of coke enhanced. Combined with the results of FT-ICR MS of toluene-soluble soft coke at different time-on-stream, the increase in condensed aromatics in the toluene-soluble soft coke performed on 60 min suggests that the coke precursors have already dehydrogenatedandcondensated in the early stage, whereas the formed coke is still soluble in toluene. In the advanced stage of the residue hydrotreating reaction, owing to the limitation of the catalytic capacity, the dehydrogenation-condensation reaction was intensified, which contributed to the further increase in coke aromaticity, hard coke which is difficult to remove even further reducing the catalytic activity.

The RAX-4000 para-xylene (PX) adsorbent has undergone its first industrial application in a 1.0 Mt/a PX adsorption separation unit at SINOPEC Hainan Petrochemical Co., Ltd. in 2019. The full-load calibration assessment results showed that the average purity of the PX product was 99.81% with the average yield of 98.0%. Since the unit start-up it has been running stably and has undergone shutdowns for maintenance and restarts during the five years. The average purity of the PX product was 99.76% with the average yield of 98.0% from January to September in 2024. The pressure drop in the adsorption tower varied regularly with the load and remained relatively stable, achieving long-term stable operation of the unit.

An analysis study was conducted on the deactivated catalyst of a 2 million tons/year fixed bed residue hydrotreating unit after long-term operation in SINOPEC Jinling Petrochemical Co.,Ltd. The variation of metal deposition along the flow direction on the catalysts, radial distribution of deposited metal on the catalyst cross-section, relationship between sulfur content and metal deposition, and the carbon deposition on different catalysts were investigated. The deposition of Fe and Ca showed a clear decreasing trend along the flow direction, while the deposition of Ni and V first increased and then decreased along the flow direction. The deposition distribution of different metals on the catalysts was mainly related to the form of metal existence in the residue and the performance of series catalysts. Fe and Ca were concentrated on the outer surface of the catalyst, while Ni had a relatively uniform radial distribution in the cross-section. The radial distribution uniformity of V in the catalyst cross-section gradually decreased along the flow direction, mainly related to the pore structure properties of different types of catalysts. The amount of carbon deposition on the catalyst along the flow direction first decreased and then increased, which is related to the dynamic changes of the residue properties and the operating temperature of unit during the reaction process. Based on the above analysis study, follow-up improvement suggestions had been proposed.

4,4'-dicyclohexyl biphenyl (4,4'-DCBP) and 4-cyclohexylbiphenyl (4-CBP) were synthesized by MCM-22 zeolite catalyzed reaction between biphenyl and cyclohexene. The MCM-22 zeolite modified by Mg or Co was prepared by ordinary impregnation method, the difference between complexed impregnation with citric acid and common impregnation was compared, and the samples were characterized by XRD, BET, NH3-TPD and SEM, and the catalytic performance was evaluated under the conditions of n(biphenyl):n(cyclohexene)=1:1.5, an initial pressureof 0.5 MPa,a reaction temperature of 230°C, and areaction time of200 min. The results showed that the two impregnation methods reduced the crystallinity, specific surface area, acid content and acid strength of zeolite. Complexation impregnation can effectively prevent metals from entering the molecular sieve pores, thereby reducing the blockage of the pores by Mg under higher loads, but complexing impregnationof Co at 4% and more than 4% loading causes excessive coverage of metal oxides on the surface of molecular sieves. The 4Co MCM-22 zeolite prepared by 4% ofCo by common impregnation showed the best catalytic performance, and obtained a biphenyl conversion rate of 56.5%, a target product selectivity of 67.2% and a target product yield of 38.0%.

Conventional TS-1 zeolite has the problems of limited number and poor accessibility of active sites (framework titanium species), reducing its catalytic performance for olefin epoxidation. To address these issues, a nano TS-1 zeolite with high framework titanium content was synthesized using a combination of solvent-complexed titanium source and pre-hydrolyzed silicon source via steam-assisted crystallization, and compared with conventional TS-1 zeolite with high framework titanium contentprepared using hydrothermal crystallization. The results show that compared with commercial and synthesized conventional TS-1 zeolites, the resultant nano TS-1 zeolite owns smaller crystal size, abundant external specific surface and higher framework titanium content. As a result,when applied to the 1-hexene epoxidation reaction, the resultant nano TS-1 zeolite demonstrates superior catalytic performance compared to the reference catalysts, reflected by a 1-hexene conversion of 70.4%, with selectivity and yield of 1,2-epoxyhexane at 94.0% and 66.2%, respectively.

Using benzene and ethanol as solvents, Soxhlet extraction was used to pretreat the spent catalyst for FCC gasoline hydrodesulfurization. Physical adsorption analyzer, carbon and sulfur analyzer, thermogravimetric analyzer, TPO-MS, SEM-EDS were used to characterize the deactivation catalysts from different bed layers, in order to determine the best regeneration conditions and replacement plan. The results showed that the main reasons for deactivation of the catalysts were arsenic poisoning and carbon deposition, the carbon deposition was the most serious in the middle and lower of the reactor along with the direction of stream, the amount of carbon deposited on the top and bottom of the reactor is equal. It is necessary to eliminate the serious arsenic poisoning catalyst at the top and to be replaced by fresh catalyst in the replacement plan, and to prolong the calcination time at low temperature less than 200 ℃ when the spent catalyst is regenerated, and finally to control the regenerating temperature between 400 ℃ and 450 ℃. The results showed that the overall performance of the catalyst regenerated at 450 ℃ was the best, the desulfurization rate was 92.6% , the selectivity was 76.5% , and the activity was restored to 98% of the fresh catalyst.

The production of high-quality lubricating base oil (referred to as base oil) is a significant way for refining companies to enhance economic benefits,alkylation technology is one of the important methods for producing base oil.In this paper, a safe and environmentally friendly chloroaluminate ionic liquid (IL) was selected as the catalyst to catalyze the alkylation reaction of isobutane with 1-hexadecene. The effects of the composition of the IL, as well as the process conditions including reaction temperature, volume ratio of ionicliquid to hydrocarbon (IL/HC), stirring rateand the molar ratio of isobutane to olefin (I/O) on the performance of the alkylation reaction were investigated. The experimental results showed that by using the optimized composite ionic liquid (CIL) [Et₃NH]Cl-1.6AlCl₃-0.3CuCl as a catalyst, along with appropriate volume ratio of IL/HC, raising the molar ratio of I/O, accelerating the stirring rate, and lowering the reaction temperature could effectively enhance the conversion of 1-hexadecene and significantly increase the selectivity of the target C₂₀ component. Under the optimal process conditions of a reaction temperature of 15℃, a stirring rate of 1300 r/min, avolume ratio of IL/HC of 1:2.8 and a molar ratio of I/O of 30:1, the conversion rate of 1-hexadecene could reach 99.8%,the selectivity of C₂₀ components was above 92%, which could meet the quality requirements for group III⁺ lubricating base oil.

Both seed and CTA serve as common template agents in the synthesis of hierarchical ZSM-5 zeolites. However, their specific roles in the synthesis process remain unclear. The hierarchicalZSM-5 zeolites were successfully synthesized by using a 1.5% of seed solution and various CTA contents. The physical and chemical properties of the synthesized zeolites were characterized using X-ray powder diffraction, scanning electron microscopy, low-temperature N₂ adsorption-desorption, and Fourier-transform infrared techniques. The investigation revealed that the CTA content exerted a significant influence on the synthesis of ZSM-5 zeolites, with CTA contributing to framework filling, charge balancing, and acting as a mesoporous template, while the seed solution primarily served as a structure-directing agent. Furthermore, through the utilization of the conversion of C₈ aromatic hydrocarbons as a probe reaction, it was demonstrated that the catalyst containing hierarchical ZSM-5 zeolites synthezed by seeds and CTA exhibited enhanced conversion rates for ethylbenzene and m-xylene compared to samples synthesized exclusively with a seed solution.

Removing olefins from reformate oil is a necessary operation to ensure that the bromine index of xylene feeds meets the design requirements. Traditional clay method have problems such as short service life, frequent change, and environmental pollution. It is necessary to find alternatives with long service life and good effect of deolefin. The application and current situation of mainstream liquid phase hydrogenation technology and molecular sieve catalyst technology for moving olefins were analyzed and compared. Considering the two aspects of device investment and device application, the molecular sieve catalyst DOT-300 was selected as a replacement plan for clay, and the bromine index of the feed and product before and after the application of the scheme was compared. The application effect of molecular sieve catalyst deolefin technology was verified. The application of this scheme can ensure that the bromine index of xylene products is qualified and the stable operation of the device, which is conducive to the long-term operation of the device.

During the maintenance period in 2023, a domestic pre-hydrotreating unit utilized the presulfurized catalyst FH-40A. The loading and commercial use effects of the new pre-hydrotreating catalyst are comprehensively analyzed. The commercial application results show that the pre sulfurized catalyst FH-40A has advantages such as simplifying the start-up steps, shortening the start-up time, and reducing environmental pollution. Compared with the oxidation type pre-hydrotreating catalyst, it can save 40 hours of start-up time. During the start-up process, the concentration of hydrogen sulfide in the circulating hydrogen detected remained at an ideal level. After 6 months of operation, the catalyst exhibited stable and excellent catalytic performance.

Accurately controlling the operating parameters of the mobile bed propane dehydrogenation reaction system is the foundation for the catalyst to exert its reaction performance and ensure the long-term high production capacity operation of the device. Based on the calibration and operation data of the Oleflex process propane dehydrogenation unit of a certain company, it was found that reasonable control of the reaction temperature can achieve a suitable equilibrium value for the reaction capacity. Further increasing the reaction temperature can increase the propylene production capacity, but the technical and economic rationality needs to be comprehensively considered; Under conditions where the device has sufficient regeneration capacity and the reaction effluent compressor (REC) allows, reducing the reaction pressure can improve the conversion rate and selectivity of the reaction; Under high production capacity conditions, the volumetric air velocity of the feed should be carefully adjusted. When adjusting the feed flow rate beyond 100% of the design load, it is necessary to fully evaluate the risks of creating "cavities" and "wall sticking" issues.Reducing the hydrogen to hydrocarbon ratio is an effective measure to improve the conversion rate and selectivity of propane dehydrogenation, but it will increase the amount of catalyst coke deposition. A balance should be found between improving the selectivity of propane dehydrogenation reaction, the performance of the circulating hydrogen compressor, and catalyst coke deposition.

As a clean fossil energy, the application of natural gas in refining enterprises can not only reduce environmental pollution and greenhouse gas emissions, but also improve energy utilization efficiency and economic benefits of enterprises. Meanwhile, the effective utilization of natural gas in refining enterprises plays an important role in promoting the sustainable development of the industrial chain. In addition to being used as fuel, optimizing the utilization of deep processing routes can improve energy efficiency, reduce production costs, and enhance efficiency. This article compares and analyzes three natural gas utilization routes to produce hydrogen,carbon monoxide or acetylene in refining enterprises, studies countermeasures through application examples, and puts forward relevant suggestions on how to further tap the potential of natural gas utilization and enhance its value in the future.

SINOPEC Henan Refining & Chemical Co.,Ltd. in order to improve the 200 kt/a alkylation unitalkylated oil yieldand solve the problem of high gasoline vapor pressure in the summer, mixing a certain amount of C₅ components from gas fractionator (C₅) to the alkylation unit, and the yield of alkylated oil was improved successfully, but during the blending of C₅, the relevant pipelines and equipments of the device were prone to clogging, resulting in the C₅ could not be blended successfully.In response to the situation, through the analysis of the clogging situation and causes, it was found that the N-methyldiethanolamines impurity carried by C₅ were the main cause of clogging of the pipelines and equipments. Then, the impurities in the C₅ were successfully removed by leading the C₅ to the water washing system of the alkylation unit, which made the mass concentration of nitrogen of the washing water in the water washing tank of the C₅ and the water samples in the total discharge of the neutralization pool be controlled stably at about 126.1mg/L and 47.4mg/L respectively, and the pH of the total discharge water sample of the neutralization pool was stabilized at the range of 6—7, which was in line with the requirements of the back-channel emission indexes. And after the water-washed C₅ was introduced into the alkylation reaction system, the differential pressure of the original easily clogged pipeline and equipment of the device was stable and controllable, and the key production parameters such as feedstock alkene ratio, reaction temperature, mass fraction of acid, acid consumption, and volume fraction of isobutane could be stably controlled at about 1.3, 3℃, 92%, 83.79kg/t, and 88.8% respectively. While ensuring the smooth operation of the plant, the high quality alkylated oil products with octane number of 94.6, Reid's saturated vapor pressure of 47.91 kPa, final distillation point of 191.1℃, density(20℃) of 695.5kg/m³ and copper flake corrosion grade of 1a were obtained, and the target of alkylated oil yield increase of 3.48 percentage points was achieved successfully, which provided strong guarantee and support for the improvement of the quality of gasoline in the refinery as well as the increase of the efficiency of the refinery.

Residue to chemicals (RTC) technology is a novel technology that uses inferior heavy oil as raw material to produce more low-carbon olefins. In the context of"oil conversion" and "dual carbon", RTC plays an important role in the adjustment of product structure and low-carbon transformation and development in the refining industry. An in-depth analysis was conducted on the operational data of a 3.0 Mt/a RTC device that has already been put into production and the current situation of two RTC devices under construction. It is recommended to set the reaction pressure of the RTC device at 130–160 kPa. Using dry gas as dilution steam, and the proportion of injected dilution steam should be controled within 20%. The raw material type and recycling capacity of the second riser should be reasonably set based on the economic efficiency of downstream equipment utilizing C4 resources.

In order to meet the demand for high-quality raw materials in steam-crackedethyleneunits, SINOPEC Research Institute of Petroleum Processing Co.,Ltd.(RIPP) had developed the first generation of cost-effective MHUG-E technology and catalyst. The diesel and light naphtha fractions produced by using this technology can be used as high-quality ethylene raw materials. Fujiang Refining & Petrochemical Company Limited (FREP) uses MHUG-E technology to process straight run diesel. The product diesel shows a high-quality steam-crackedethylene raw material, with a conversion rate of only 9.5%, the mass fraction of paraffin of the product diesel increased from 47.5% to 55.7%, and the BMCI value decreased from 29.5 to 18.7. The results of long-term industrial operation show that the industrial equipment has been running stably for 70 months, with a very slow catalyst deactivation rate. The diesel product has a cetane index greater than 55, which is not only a high-quality national Ⅵclean diesel, but also a high-quality steam-cracked ethyleneraw material.

In order to study the suitable technical route for the processing of products of slurry bed residual oil hydrocracking unit, SINOPEC Maoming Company entrusted SINOPEC Research Institute of Petroleum Processing Co., Ltd. to conduct experiments on various processing technology using the light oil fraction and vacuum gas oil(VGO) fraction produced by the unit as raw materials, and industrial applications have been carried out. The results indicate that after processing through hydroupgrading technology，heavy naphtha oil products is a high-quality heavy feedstock because of the high aromatic potential，the product diesel meets the national Ⅵ standard for automotive diesel. The VGO fraction can be used as a blending component for ship combustion after shallow desulfurization. After high-pressure hydrogenation treatment, the mass fraction of hydrogen of the VGO fraction can be increased to over 12.0%, and the mass fraction of nitrogen can be reduced to less than 500 μg/g. It can be used as a high-quality catalytic cracking feedstock. The VGO fraction can be converted into high-quality catalytic cracking feedstock through high-pressure mild hydrocracking process. After catalytic cracking technology conversion, the ethylene yield is 11.74%, the propylene yield is 20.65%, and the sum of ethylene, propylene, and butene yields is 42.62%. The industrial practice has verified the results of the pilot-scale test.

Rapid and accurate determination of fatty acid methyl ester (FAME) content in marine fuel oil is of great significance for quality control of marine fuel. This article uses mid infrared spectroscopy analysis technology combined with chemometric methods to quantitatively analyze the FAME content in marine fuel oil. Based on the correlation between FAMEinfrared characteristic peak intensity and volume fraction, a partial least squares analysis model was used to establish an analysis model, which had good accuracy and stability. The regression coefficients of the models based on spectra collected by two different types of instruments are both greater than 0.99, with cross validation standard deviations of 0.2644 and 0.1517, and sample repeatability standard deviations of 0.08% and 0.17%, respectively. The results indicate that mid infrared spectroscopy can quickly and accurately detect the FAME content in marine fuel oil, providing a practical analytical tool for quality monitoring of marine fuel oil.

The characteristics of toxic organics in typical petrochemical wastewater and different polar components were explored. And the biotoxicity effects of petrochemical wastewater were evaluated combined with acute biotoxicity and genotoxicity. According to gas chromatography-mass spectrometry（GC-MS） analysis, the strong-polar organics in petrochemical wastewater mainly included nitrogen-containing heterocycles and amines, and the non-polar organics mainly included phenols and alkanes. The toxic unit (TU) and tail DNA percentage (Tail DNA %) of petrochemical wastewater were 10.49 and 98.01, respectively. It indicated that the petrochemical wastewater has strong acute biotoxicity and genotoxicity. The TU of strong-polar component was 19.88, which was the key organics inducing the acute biotoxicity of petrochemical wastewater. The Tail DNA % of the non-polar component was 90.07, which was the main organics inducing the genotoxicity of petrochemical wastewater. According to oxidative stress analysis, the reactive oxygen species (ROS) increase rate caused by petrochemical wastewater was 5.32%, indicating that petrochemical wastewater can induce oxidative stress, thereby inducing the acute biotoxicity and genotoxicity on Tetrahymena thermophilecells. Based on the above results, the biotoxicity effects of petrochemical wastewater were clarified and its potential main toxic organics were identified, thus providing theoretical guidance for priority control of toxic organics in petrochemical wastewater and protection of water environment safety.

Waste drilling slurry is one of the main pollutants generated during oilfield drilling operations, and improper disposal can pose a threat to surrounding soil and groundwater. In this study, modified biochar was used as a carrier to immobilize the selected highly efficient composite degradation microbiota. The modified biochar material exhibited excellent porous properties and abundant surface functional groups, enabling high efficiency in microbial loading. During the 63-day remediation period, the degradation rates of COD, TOC, and NH4+-N in waste slurry by NaOH-EP@Bacteria were 81.09%, 65.86%, and 83.27%, respectively. Enzyme activity assays and high-throughput sequencing revealed that, compared to other treatment groups, NaOH-EP@Bacteriaexhibited higher microbial species abundance and activity in the rehabilitated soil, which had a positive impact on enhancing microbial tolerance and organic matter degradation efficiency. This study followed the principle of treating waste with waste and provided a low-cost and effective method for using abandoned wheat straw to prepare immobilized microorganisms material to remediate waste drilling slurry. It opened a new way to solve the pollution of abandoned drilling slurry in oil fields.

Based on the actual situation of silver catalyst production equipments, an advanced and efficient wastewater treatment technology was developed. By adopting the technology route of reaction/sedimentation/membrane treatment, comparative experiments were conducted on different precipitation reaction materials and filtration media to design an experimental device with a key equipment of expanding drum filter.Compared with the conventional industrial process, the aeration process has been cancelled and the Ag⁺ concentration in wastewater tends to be stabilized after the static placing time reaches 2 h. Moreover, the concentration of Ag⁺ in the wastewater could be reduced from 200—1500 mg/L to 0.05 mg/L or less. This technology could meet the industrial wastewater discharge standards and achieve the recycling and utilization of Ag⁺, bringing a great application prospect.

To diagnose the cause of amine solution blackening leading absorption column blockage in a petrochemical sulfur recovery unit, a systematic analysis was conducted using methods such as filter disassembly, scale element detection, and amine composition analysis. The results indicated that the black substances were primarily composed of iron sulfide (FeS). The study found that when lean and rich amine streams cross-contaminate, iron sulfide initially forms a protective film on the surfaces of pipelines and equipment. However, changes in tail gas composition or operating conditions can cause the film to detach, allowing FeS particles to circulate with the amine solution into the absorber, leading to a rise in differential pressure. Based on process characteristics and safety risk assessments, measures such as stream isolation, passivation cleaning, and amine replacement were proposed and implemented. Following these actions, the absorber differential pressure significantly decreased, and the acid gas processing capacity returned to normal levels. This study provides a practical engineering approach and technical reference for preventing amine blackening and tray blockage in similar sulfur recovery units.

With the crude oil getting heavier and more inferior continuously, residue hydrogenation process has gradually become the mainstream technology for the treatment of heavy oil. In the residue hydrogenation reaction process, impurities such as sulfur, nitrogen, nickel and vanadium are effectively removed from the residue, and the thick aromatic hydrocarbons of large molecules are hydrocracked into light small molecules, providing cleaner and more suitable raw materials for the subsequent process. However, due to the extremely complex molecular composition of residue and its hydrogenation reaction system, accurate simulation of residue hydrogenation reaction process is a key and difficult point, and is also a current research focus. In order to solve the problem of steady state simulation, a dynamic parameter model based on gamma distribution and a continuous lumped axial diffusion model are proposed in this paper. The complexity of the model is simplified and the generality of the model is improved by gamma distribution function. The axial diffusion model is used to simulate the flow mass transfer process of fixed bed residue hydrogenation, and the trust region optimization algorithm is used to correct the model parameters by using industrial data, which greatly improves the computational efficiency and convergence rate of the model correction compared with other optimization algorithms. In addition, two other residue hydrogenation process conditions were used to verify the model and the optimized model parameters, and the results showed that the prediction accuracy and prediction efficiency were high, indicating that the simplified mechanism model based on gamma distribution had high prediction accuracy, calculation efficiency and calculation potential.

Anaerobic ammonium oxidation (Anammox) process is considered the most economical treatment process in the field of sewage biological nitrogen removal, with advantages such as low energy consumption, no need for external organic carbon sources, and low sludge production. However, Anammox bacteria are sensitive to the environment, which affects the nitrogen removal performance of Anammox in treating high-salinity wastewater. Thispaper briefly describes the impact of different salts and their concentrations on the nitrogen removal performance, sludge granules, extracellular polymers, and microbial community structure of Anammox, and summarizes the salt tolerance inhibition mechanisms of anammox bacteria from aspects such as osmotic pressure, energy metabolism, and enzyme inhibition. It also discusses research on coping with high salinity stress and prospects for future studies on the impact of different salts and their concentrations on the Anammox process, aiming to provide references for the optimization of Anammox processes in treating saline nitrogen-rich wastewater.

Increasing the production of light olefins in fluid catalytic cracking (FCC) unit is an effective mean for many refineries to optimize product distribution and enhance economic benefit. It is also one of the critical pathways to transform the refining industry towards the chemical industry.The catalysts and additives for enhancing light olefins production in FCC, along with their technological features, was reviewed over the past two decades both domestically and internationally. The applications of some products in domestic refineries were summarized, aiming to provide references for refineries in selecting suitable products to increase light olefins production. Currently, the technology for enhancing light olefins production is maturing, and the continued optimization of zeolite and matrix properties will be the unchanging theme in the future. Catalyst assembly technology may play a significant role in constructing highly accessible catalysts and additives with hierarchical pores.

1,2,4-Butanetriol is an important C₄ polyol with widespread applications in military, pharmaceutical, and plastic industries. Its synthesis methods primarily include chemical synthesis, microbial fermentation, and catalytic hydrogenolysis of biomass. Traditional chemical synthesis offers advantages such as simplicity in process and high product purity but faces challenges related to environmental pollution and resource consumption. Microbial fermentation, based on microbial technologies, is environmentally friendly and renewable but requires careful attention to yield and cost control. Biomass catalytic hydrogenolysis demonstrates promising application prospects.However, the reaction mechanisms and catalysts in this method remain underexplored. To achieve efficient and sustainable synthesis of 1,2,4-butanetriol, future efforts should focus on the design of novel catalysts and the elucidation of their structure-performance relationships, thereby accelerating the development of green synthetic processes.