Efficient Synthesis of Dimethyl Ether from Methanol in a Bifunctional Zeolite Membrane Reactor

A sandwich FAU–LTA zeolite dual‐layer membrane has been developed and used as a catalytic membrane reactor for the synthesis of dimethyl ether (DME). In the top H‐FAU layer with mild acidity, methanol is dehydrated to DME. The other reaction product, water, is removed in situ through a hydrophilic Na‐LTA layer, which is located between the porous alumina support and the H‐FAU top layer. The combination of mild acidity with the continuous removal of water results in high methanol conversion (90.9 % at 310 °C) and essentially 100 % DME selectivity. Furthermore, owing to the selective and continuous removal of water through the Na‐LTA membrane, catalyst deactivation can be effectively suppressed.     

Methanol synthesis from carbon dioxide and hydrogen using a ceramic memebrane reactor

Methanol was synthesized from CO₂ and H₂ using a silica/alumina composite membrane reactor, which improved methanol conversion to 150% of the value in conventional reactor, by in situ removal of water formed in catalytic reaction. This revised version was published online in June 2006 with corrections to the Cover Date.     

共沉淀镍催化剂用于膜反应器中高碳烃类燃料水蒸气重整反应

 采用共沉淀法制备了NiO/La-Al2O3催化剂,利用低温N2物理吸附、程序升温还原、 H2-O2化学吸附和X射线衍射对催化剂进行了表征,并将该催化剂应用于Pd膜反应器中高碳烃类燃料水蒸气重整反应. 结果表明,催化剂中NiO与载体间存在较强的相互作用. 与常规固定床反应器相比,在膜反应器中,由于高渗透性能的Pd金属复合膜能选择分离氢气,结果氢气产率得到了明显的提高,甲烷的生成得到了有效抑制,并且在接近实用的反应条件下,依然能够得到高的氢气产率和回收率. 高碳烃类燃料水蒸气重整反应制氢的过程可以在一个膜反应器中,利用一种催化剂在反应温度低于823 K的温和条件下实现.     

Study on methanol reforming–inorganic membrane reactors combined with water–gas shift reaction and relationship between membrane performance and methanol conversion

When a methanol reforming–membrane reactor is employed as a hydrogen generator for proton exchange membrane fuel cell (PEMFC), three important aims should be simultaneously achieved in one process, which are methanol conversion improvement, high hydrogen recovery, and high CO removal efficiency. To achieve the aims, we investigated five different configurations of a membrane reactor (a methanol reforming–microporous membrane (MMi) reactor, methanol reforming–mesoporous membrane (MMe) reactor, methanol reforming–mesoporous membrane–water–gas shift (MMeW) reactor, methanol reforming–macroporous membrane (MMa) reactor and methanol reforming–macroporous membrane–water–gas shift (MMaW) reactor). As a result, the MMi reactor was not suitable for a hydrogen carrier of PEMFC due to low hydrogen recovery. The MMe and MMa reactor showed low CO removal efficiency due to low permselectivity of the mesoporous and macroporous membrane. In contrast, the MMeW and MMaW reactor gave simultaneously methanol conversion improvement, high hydrogen recovery, and high CO removal efficiency in one process. The low CO removal efficiency due to low permselectivity of the mesoporous and macroporous membrane was significantly enhanced by the water–gas shift reaction in the permeate side of the MMeW and MMaW reactor. In addition, based on the reaction results in the MMi, MMe and MMa reactor, it was confirmed that methanol conversion in a membrane reactor system is higher as a membrane used in a membrane reactor has higher total permeance difference (∑permeance of products − ∑permeance of reactants).     

Modeling of Fischer-Tropsch Synthesis in a Slurry Reactor with Water Permeable Membrane

Fischer-Tropsch synthesis is an important chemical process for the production of liquid fuels and olefins. In recent years, the abundant availability of natural gas and the increasing demand of olefins, diesel, and waxes have led to a high interest to further develop this process. A mathematical model of a slurry membrane reactor used for syngas polymerization was developed to simulate and compare the maximum yields and operating conditions in the reactor with that in a conventional slurry reactor. The carbon polymerization was studied from a modeling point of view in a slurry reactor with a water permeable membrane and a conventional slurry reactor. Simulation results show that different parameters affect syngas conversion and carbon product distribution, such as the hydrogen to carbon monoxide ratio, and the membrane parameters such as membrane permeance.     

A STUDY ON MEMBRANE PROCESS WITH |?-ALUMINA MEMBRANE REACTOR FOR ETHYLBENZENE DEHYDROGENATION TO STYRENE

The membrane reaction of ethylbenzene(EB) dehydrogenation to styrene(ST) has been studied by using K2O/Fe2O3 industrial catalyst and alumina ceramic membrane developed by our institute. In comparison with the packed bed reactor (that is, plug flow reactor, abbr. PFR) in industrial practice, the yield of styrene was increased by 5%~10% in the membrane reactor. Furthermore, mathematical modeling of membrane reaction has been studied to display the principle of optimal match between the catalytic activity and the membrane permeability.     

Green process of fuel production under porous γ-Al2O3 catalyst: Study of activation and deactivation kinetic for MTD process

One of the methods of industrial dimethyl ether production is the catalytic dehydration of methanol. In this research work, methanol dehydration reactor has been modeled using continuous model and its results have been compared with experimental works and Voronoi pore network model. A 1D heterogeneous dispersed plug flow model was utilized to model an adiabatic fixed-bed reactor for the catalytic dehydration of methanol to dimethyl ether. The mass and heat transfer equations are numerically solved for the reactor. The concentration of the reactant and products and also the temperature varies along the reactor, therefore the effectiveness factor would also change in the reactor. We used the the effectiveness factor that was simulated according to the diffusion and reaction in the catalyst pellet as a Voronoi pore network model. Sensitivity analysis was performed to determine the influence of T, P and weight hourly space velocity on performance of the chemical reactor. Acceptable agreement was reached between the measured and the model data. The results showed that the maximum reaction conversion was obtained about 90 % at WHSV = 10 h^?1 and T = 560 K, while the inlet temperature (T_inlet) had a greater effect on methanol conversion. In addition, the effect of water in the feed on methanol conversion was quantitatively studied. Also, the deactivation kinetics of γ-Al₂O₃ heterogeneous-acidic catalyst in methanol to dimethyl ether dehydration process was studied using integral analysis method. Based on independent deactivation kinetics, a second order was found that accurately fitted the experimental conversion time data. The main reaction activation energies and catalyst deactivation energies were 143.1 and ?102.1 kJ/mol, respectively.     

膜反应器在乙苯脱氢反应过程中的应用(英文)

以γ－Ａｌ２Ｏ３微孔陶瓷膜构成膜反应器（ＣＭＲ），使用ＧＳ－０５工业催化剂，在工业过程的操作条件下，研究了乙苯脱氢生产苯乙烯膜的反应规律。与工业上的固定康（ＰＦＲ）过程比较，有膜反应过程产率可提高５％－１０％。在本研究的条件下，股反应的优化实际上就是催化剂反应活性和膜渗透性的匹配。     

Studies of the Methane Steam Reforming Reaction at High Pressure in a Ceramic Membrane Reactor

The effects of temperature and pressure on the steam reforming of methane 3H2+CO) were investigated in a membrane reactor (MR) with a hydrogen permeable membrane. The studies used a novel silica-based membrane prepared by using the chemical vapor deposition (CVD) technique with a permeance for H2 of 6.0×l0-8 mol·m-2·s-1·Pa-1 at 923 K. The results in a packed-bed reactor (PBR) were compared to those of the membrane reactor at various temperatures (773-923 K) and pressures (1-20 atm, 101.3-2026.5 kPa) using a commercial Ni/MgAl2O4 catalyst. The conversion of methane was improved significantly in the MR by the countercurrent removal of hydrogen at all temperatures and allowed product yields higher than the equilibrium to be obtained. Pressure had a positive effect on the hydrogen yield because of the increase in driving force for the permeance of hydrogen. The yield of hydrogen increased with pressure and reached a value of 73×10-6 mol·g-1·s-1 at 2026.5 kPa and 923 K which was higher by 108% than the value of 35×10-6 mol·g-1·s-1 obtained for the equilibrium yield. The results obtained with the silica-based membrane were similar to those obtained with various other membranes as reported in the literature.     

间歇反应器内醋酸丁酯酯化反应与渗透汽化集成过程的模型计算

 建立了一个间歇反应器内酯化反应与渗透汽化集成过程的数学模型, 用于描述反应和脱水同时进行的过程. 该模型考虑了反应体系中所有组分的渗透量影响以及混合物的非理想热力学行为. 选择乙酸和正丁醇生成醋酸丁酯的酯化反应与 PVA 膜渗透汽化集成过程为研究体系, 将模型结果与文献中已报道的实验数据进行对比, 验证了该模型的有效性. 结果表明, 采用渗透汽化脱除酯化反应的水分将提高酯的产率. 对温度、反应物初始比、膜面积与反应体积比以及催化剂浓度几种操作条件对集成过程性能影响进行了参数的分析. 根据结果讨论得到该膜过程与反应集成过程的优化操作条件.     

NaA分子筛膜蒸汽渗透促进丙烯酸/乙醇的酯化反应

以对甲苯磺酸为催化剂,利用亲水性NaA分子筛膜蒸汽渗透过程,选择性地将丙烯酸和乙醇酯化反应产物中的水原位分离出反应器,打破反应平衡限制,使反应不断向右进行,反应15 h丙烯酸转化率达到100%。     

惰性膜反应器用于丁烷氧化脱氢制丁烯和丁二烯反应

采用浸渍法制备了Ｖ－Ｍｇ－Ｏ催化剂,利用ＸＲＤ和ＢＥＴ对催化剂进行了表征,比较了固定床反应器（ＦＢＲ）、惰性膜反应器（ＩＭＲ）与混合式惰性膜反应器（ＭＩＭＲ）用于丁烷氧化脱氢制丁烯和丁二烯反应的性能,采用在陶瓷丰部分涂釉的方法获得臃符合实验要求的惰性膜,利用惰性膜沿反应器轴向分布氧气,降低反应区氧气分压,从而提高目的产物的选择性,通过优化进料方式,在２０ＭＭＲ反应器中得到了６６％的Ｇ４烯烃选择性３     

High selective ethylbenzene obtainment through alkylation of dilute ethene with gas phase-liquid phase benzene and transalkylation feed

A novel industrial process was designed for the highly selective production of ethylbenzene. It comprised of a reactor vessel, vapor phase ethylene feed stream, benzene and transalkylation feed stream. Especially the product stream containing ethylbenzene was used to heat the reactor vessel, which consisted of an alkylation section, an upper heat exchange section, and a bottom heat exchange section. In such a novel reactor, vapor phase benzene and liquid phase benzene were coexisted due to the heat produced by isothermal reaction between the upper heat exchange section and the bottom heat exchange section. The process was demonstrated by the thermodynamic analysis and experimental results. In fact, during the 1010 hour-life-test of gas phase ethene with gas phase-liquid phase benzene alkylation reaction, the ethene conversion was above 95%, and the ethylbenzene selectivity was above 83% (only benzene feed) and even higher than 99% (benzene plus transalkylation feed). At the same time, the xylene content in the ethylbenzene was less than 100 ppm when the reaction was carried out under the reaction conditions of 140–185 °C of temperature, 1.6–2.1 MPa of pressure, 3.0–5.5 of benzene/ethylene mole ratio, 4–6 v% of transalkylation feed/(benzene+transalkylation feed), 0.19–0.27 h^?1 of ethene space velocity, and 1000 g of 3998 catalyst loaded. Thus, compared with the conventional ethylbenzene synthesis route, the transalkylation reactor could be omitted in this novel industrial process.     

Highly selective ethylbenzene production through alkylation of dilute ethylene with gas phase-liquid phase benzene and transalkylation feed

A novel industrial process was designed for the highly selective production of ethylbenzene.It comprised of a reactor vessel,vapor phase ethylene feed stream,benzene and transalkylation feed stream.Especially the product stream containing ethylbenzene was used to heat the reactor vessel,which consisted of an alkylation section,an upper heat exchange section,and a bottom heat exchange section.In such a novel reactor,vapor phase benzene and liquid phase benzene were coexisted due to the heat produced by isothermal reaction between the upper heat exchange section and the bottom heat exchange section.The process was demonstrated by the thermodynamic analysis and experimental results.In fact,during the 1010 hour-life-test of gas phase ethene with gas phase-liquid phase benzene alkylation reaction,the ethene conversion was above 95%,and the ethylbenzene selectivity was above 83% (only benzene feed) and even higher than 99% (benzene plus transalkylation feed).At the same time,the xylene content in the ethylbenzene was less than 100 ppm when the reaction was carried out under the reaction conditions of 140-185℃ of temperature,1.6-2.1 MPa of pressure,3.0-5.5 of benzene/ethylene mole ratio,4-6 v% of transalkylation feed/(benzene+transalkylation feed),0.19-0.27 h-1 of ethene space velocity,and 1000 g of 3998 catalyst loaded.Thus,compared with the conventional ethylbenzene synthesis route,the transalkylation reactor could be omitted in this novel Industrial process.     

C302铜基甲醇合成催化剂颗粒设计Ⅱ. 颗粒结构对Lurgi型合成反应器性能的影响

基于本文（I）报的研究结果，以固定床反应器二维非均相数学模型为基础，模拟考察了C302铜基甲醇合成催化剂颗粒设计对Lurgi型合成反应器性能的影响。结果表明，由于颗粒结构设计改变了粒内反应－扩散耦合行为的相互匹配关系，使得催化剂的宏观反应活性发生变化，进而对反应器的操作性能产生显著的影响（包括反应器生产能力、温度和浓度分布特性、床层压力降和热点温度等），为提高反应器的生产能力和改善反应器的操作性能，进行催化剂颗粒的适宜结构设计是非常必要和有价值的。     

甲醇驱动的环氧丙烷连续生物合成

采用甲醇蒸气作为碳源对甲基弯菌IMV 3011进行驯化培养,然后逐渐增加液态甲醇的浓度使其适应,得到了能耐受甲醇(φ(MeOH)=1%)的甲基弯菌IMV 3011.对甲基弯菌IMV 3011进行甲烷-甲醇共培养可得到大量具有甲烷单加氧酶(MMO)活性的细胞.研究了添加甲醇对甲基弯菌IMV 3011生长和MMO活性的影响,发现甲醇能够促进甲基弯菌IMV3011的生长.在批式反应器中,添加甲醇能够提高甲基弯菌IMV 3011的催化环氧化能力,说明甲醇可以作为电子供体通过再生辅酶NADH驱动环氧丙烷合成.考察了在膜反应器中用细胞悬浮液连续合成环氧丙烷的可行性.结果表明,通过192 h连续抽提产物环氧丙烷,避免了其对环氧化反应的抑制,流出液中环氧丙烷的浓度仍保持在1.35 mmol/L左右.     

Energy-efficient dehydrogenation of methanol in a membrane reactor: a mathematical modeling

A two-dimensional non-isothermal stationary mathematical model of the catalytic membrane reactor for the process of methanol dehydrogenation is described. Copper supported on the carbonaceous support was considered as a catalyst. The reaction of methanol dehydrogenation was thermodynamically conjugated with a reaction of hydrogen oxidation taking place in a shell side of the membrane reactor. The effects of various parameters on the methanol conversion and the methyl formate yield have been calculated with the developed model and discussed. Two different types of heating the gas flow were considered and compared. In the case of conjugated dehydrogenation process, the methyl formate yield reaches 77%, when the reactor outer wall was heated up to 150 °C. When the inlet gas flows in the tube and shell sides were heated up to 100 and 83 °C, correspondingly, the yield was 72%.     

自呼吸直接甲醇燃料电池膜电极的优化(英文)

针对空气自呼吸式直接甲醇燃料电池甲醇易渗透和阴极易水淹的特点,通过对催化层催化剂载量、阴极微孔层、阳极微孔层和膜等因素进行调控,对膜电极结构和性能的进行了优化.结果表明,使用高载量催化剂能有效降低甲醇渗透,但载量过高会引起传质阻力.当阳极微孔层PTFE含量为30%(bymass)时,可以有效促进CO2的均一析出,从而降低甲醇浓度梯度,减小甲醇透过.综合考虑甲醇渗透和阴极自返水,经优化后所得MEA在室温时自呼吸工作条件下,比功率密度达到33mW·cm-2,最优甲醇工作浓度为4mol·L-1.     

膜反应器中萘普生甲酯的动态拆分

在碱催化连续原位消旋条件下,利用CRL脂肪酶（Candida rugosa lipase）催化的萘普生甲酯立体选择性水解反应。动态拆分制备（S）－普生。使用硫水硅橡胶膜隔离生物催化拆分反应和碱催化消旋反应,解决了常规动态拆分反应中生物催化剂难以承受原位化学消旋苛刻反应条件的难题。为了利于从水－有机溶剂乳化体系中分离产物和克服产物抑制,将亲水半透膜引入搅拌罐反应器,在该膜反应器中进行动态拆分反应。当转化率超过60％时,产物（S）－萘普生的对映体过量值（eep)仍在96％以上,在反应过程中还发现CRL脂肪酶同工酶的转化。     

STUDIES ON THE CERAMIC MEMBRANE REACTOR FOR OXIDATIVE COUPLING OF METHANE

lntroductionNat[lralgasisanabundanresourceandtheworldreservesareestimatedtobe43trillioncubicmeers.DuetoitshightransportcostandverystablechendcalproPerty,onlylessthanlo%oftheworldproductionofnaturalgasisusedinchendcalindustriesandtheremainderisburnedasfuelforpowergeneratingandhcaing.Toincreaseitsvalueanduseitasachemicalfeedstock,naturalgasmustbeconvetaltomoreappropriatC-products.SincethepioneeringworkofKellerandBhasim(l982)atUnionCarbidell],therehasbeenconsiderableinterestinmethaneconversiont…