The study of catalytic performance of silica-supported three metallic Fe–Co–Ce catalyst prepared using impregnation procedure for Fischer–Tropsch synthesis

We apply the wet impregnation procedure to prepare the Fe–Co–Ce catalyst supported by silica. The effects of operational conditions such as temperature, pressure, and the feed ratios of reaction on the selectivity and yield were studied. The production of light olefins from syngas (CO and H₂) over this catalyst in a fixed bed reactor via Fischer–Tropsch synthesis (FTS) was investigated. The reactor tests were determined through the design experiments.The optimum condition was determined in a way that the selectivity of methane was the least and other olefins have the maximum selectivity. The results indicated that the catalyst at 350°C, 3 bar, and syngas with H₂/CO ratio 1/1 has shown the better catalytic performance for FTS.     

Evaluation and modeling of Fischer-Tropsch synthesis in presence of a Co/ZrO2 catalyst

Abstract

The present work focused on the application of response surface methodology (RSM), Box–Behnken design (BBD), for prediction of products distribution of Fischer-Tropsch synthesis (FTS) using a Co/ZrO₂ catalyst in a fixed bed reactor. The effect of four independent operating variables such as reaction temperature, pressure, space velocity and H₂/CO ratio on the responses (CH₄ and C₅⁺ selectivities) in FTS were investigated. The analysis of variance (ANOVA) results showed that the suggested quadratic models could well predict CH₄ and C₅⁺selectivities. The optimized operating condition was temperature 200.73?°C, pressure 20?bar, space velocity 1662.58?h^?1 and H₂/CO ratio 1.93.     

浆态床反应器中熔铁催化剂的费托合成反应性能

研究了浆态床反应器中熔铁催化剂的费托合成反应性能,并与固定床反应器进行了比较。实验结果表明,熔铁催化剂在浆态床反应器中具有较好的费托合成反应活性和良好的稳定性;与固定床反应器相比,浆态床反应器中CH4和CO2的选择性明显降低。考察了反应温度、反应压力、合成气空速、合成气n(H2)∶n(CO)对浆态床反应器中熔铁催化剂费托合成反应性能的影响。实验结果表明,适当调变反应条件,可有效提高熔铁催化剂的费托合成反应活性,并使产物分布得到优化。在n(H2)∶n(CO)=1.6、2.0M Pa、250℃、GHSV=3 000h-1的条件下运行900h,浆态床反应器中CO的转化率达92%左右,CH4的选择性为5%左右,CO2的选择性为40%左右。     

两段串联浆态床费托合成工艺试验研究

对铁系催化剂费托合成反应过程和反应动力学进行了深入分析,依据其反应过程的特点提出了两段串联浆态床费托合成工艺,该工艺中第一段反应器的进料仅为新鲜合成气并单程通过,第一段反应器顶部气相产物经过冷却分离出油、水产品后的气体进入第二段反应器,第二段反应器顶部气相产物经过冷却分离出油、水产品后的气体部分循环回第二段反应器继续进...     

Computer Simulation on Reaction Condition when Vinyl Acetate is Compound by Acetic Acid and Acetylene in Fixed Bed Reactor

Abstract

The macro-dynamics for synthesis of vinyl acetate on Zn(Ac)₂—acticarbon catalyst was studied. Consulting actual plant conditions by means of computer simulation, the parameters and reaction conditions for a fixed bed reactor used to produce vinyl acetate in acetylene method were calculated. The result shows that total heat transfer coefficient between catalyst bed and heat conductive oil could be affected by variety of conditions: catalyst diameter, airspeed, temperature and speed of heat conductive oil, and tube diameter in reactor. Analyzing the principles about how the factors affect the heat conduction, a laboratory reactor was made according to the analogue data. The actual temperature distribution of catalyst bed could inosculate with the analogue results roughly.     

THE ROLE OF WATER IN METHANOL SYNTHESIS

Abstract

This work focuses on the influence of water in determining the rate of methanol synthesis over CuO/ZnO/Al₂O₃ catalysts. The experimental investigations were conducted in a 1-L slurry reactor based on the novel liquid phase methanol synthesis process. The liquid medium used was a blend of paraffinic and naphthenic mineral oils with a mean molecular mass of 250. It was found that the methanol rates attained a maximum at an optimal water content which was dependent on the reaction temperature. The catalytic activity was found to decline with time at lower temperatures in the presence of a relatively large excess of water. The influence of water was also found to be firmly linked to the corresponding carbon dioxide content in the reactor feed. The experimental data bear additional significance because this was the first such study to be performed on the liquid phase process. Emphasis was therefore placed on the use of a CO-rich syngas in order to simulate anticipated process conditions.     

Study on steam reforming of naphthalene in presence of supported catalysts

Due to the limitations of existing methods, steam reforming is the most important method of hydrogen production. In this study, we intend to investigate the potential of two Rh/Al₂O₃ and Cr/Al₂O₃ catalysts in the conversion of naphthalene in the steam reforming process. For this purpose, the experimental method was first described in a fluidized bed reactor. In the next step, the effect of various parameters such as catalysts, temperature and steam/carbon ratio on naphthalene conversion was investigated. With increase in temperature from 700°C to 850°C, the naphthalene conversion increased from 43.2% to 82.8% for Rh/Al₂O₃ and from 39.0% to 77.9% for Cr/Al₂O₃. Hydrogen production increased as the injection of steam into the reactor increased which can be explained based on the principle of Le Chatelier.     

Advanced fluid-typing methods for NMR logging

In recent years,nuclear magnetic resonance(NMR) has been increasingly used for fluidtyping in well-logging because of the improved generations of NMR logging tools.This paper first discusses the applicable conditions of two one-dimensional NMR methods:the dual TW method and dual TE method.Then,the two-dimensional(T2,D) and(T2,T1) NMR methods are introduced.These different typing methods for hydrocarbon are compared and analyzed by numerical simulation.The results show that the dual TW method is not suitable for identifying a macroporous water layer.The dual TE method is not suitable for typing gas and irreducible water.(T2,T1) method is more effective in typing a gas layer.In an oil-bearing layer of movable water containing big pores,(T2,T1) method can solve the misinterpretation problem in the dual TW method between a water layer with big pores and an oil layer.The(T2,T1) method can distinguish irreducible water from oil of a medium viscosity,and the viscosity range of oil becomes wide in contrast with that of the dual TW method.The(T2,D) method is more effective in typing oil and water layers.In a gas layer,when the SNR is higher than a threshold,the(T2,D) method can resolve the overlapping T2 signals of irreducible water and gas that occurs due to the use of the dual TE method.Twodimensional NMR for fluid-typing is an important development of well logging technology.     

颗粒/整体式催化剂双层床反应器中甲烷氧化偶联反应性能

用5%Na2WO4-2%Mn/SiO2颗粒催化剂和3%Ce-5%Na2WO4-2%Mn/SBA-15/Al2O3/FeCrAl金属基整体式催化剂,构建了一种颗粒/整体式新型双层床新型甲烷氧化偶联催化反应器,评价了双层床反应器中甲烷氧化偶联反应性能,重点考察了催化剂床层高度、原料气的流向方式、反应温度、烷氧比、进料流量等与反应性能的关系。结果表明,颗粒催化剂床层高度为15mm、整体式催化剂床层高度为50mm,原料气先通过颗粒床层再通过整体式床层的方式下,具有最好的反应性能,甲烷转化率为38.4%时,乙烯选择性可达41.5%,比单床层催化剂的综合性能有明显提高。     

苯酐生产技术进展

介绍了通过邻二甲苯工艺路线生产苯酐的几种技术,包括传统的单固定床氧化反应器、开发的双固定床反应器、用马来酸酐作为液体低共熔混合物回收苯酐和基于改善的耐磨催化剂的流化床反应器。探讨了生产技术的经济性,并对催化剂技术、工艺研究与开发及其工业现状进行了综述。