Simulation of gas-solid fluidized bed reactor for F-T synthesis

Using the lumping method, CH_4, C_3H_8, C_10H_22, and C_22H_44 were chosen as themodel products, and CO as the key component. The mathematical model of a gas-solidfluidized bed reactor was established based on some hypotheses. The consumption kinetic model of CO was investigated, and the parameters were estimated by UniversalGlobal Optimization with the Marquardt method. Residual error distribution and a statisticaltest show that the intrinsic kinetic models are reliable and acceptable. A model of carbonchain growth probability was established in terms of experiments. Coupled with the Ander-son- Schulz-Flory (ASF) distribution, the amount of specific product could be obtained.Large- scale cold model experiments were conducted to investigate the distribution of thegas (solid) phase and determine the function of the voidage with the location of the catalytic bed. The change tendencies of the components in the catalytic bed at different temperatures were computed and figured out. The calculated value computed by the modelestablished for the Fe-based F-T synthesis catalyst fit the experimental value very wellunder the same operating conditions, and all the absolute values of the relative deviationsare less than 5%.

Studies on the Preparation and Catalyticproperties of Fe-C-Mn Ultrafine particle Catalyst in F-T synthesis

Based on the Fe/C ultrafine particle obtained by means of laser pyrolysis method, a series of Fe-C-Mn ultrafine particle catalysts for F-T synthesis were prepared by adding certain amounts of Mn organic compounds to the Fe/C UFP. XRD and TEM tests for the obtained catalysts showed that the active phases, α-Fe, Fe3Cand (Fe,Mn)O. were directly obtained. and that the particle size was in the range of 2-4 nm. The catalysts so obtained have stable structure, long life, high activity and selectivity for light olefins, especially for propylene. Testing of the crystal structure in the process of the reaction demonstrated the carbonide mechanism of FT synthesis and the presence of α-Fe, FexCy and (Fe, Mn)O, thus supporting the belief that these are the active phases.

Effect of Several Anions on Fe-Based Catalyst for Fischer-Tropsch Synthesis

The influence of several anions on Fe-based Fischer-Tropsch catalyst, used in the synthesis of light olefins from synthesis gas, was studied. The results indicated that the addition of anions resulted in the reduction of catalytic activity. When the anion content in the catalyst was 500 ppm, the influence of different anions on the catalysis activity was as follows： S^2- 〉Cl^-〉SO4^2-〉NO3. The addition of S^2- improved the selectivity of total hydrocarbons in the products, and Cl^- reduced this selectivity but increased the olefin content in the total hydrocarbons at the same time. When the contents of S^2- and Clin the catalyst were less than 50 ppm, their influence could be ignored. The XRD results indicated that the addition of anions reduced the contents of α-Fe and FeaC, which were the active components in the catalyst.

神华费托合成催化剂SFT418应用性能研究

经过实验室配方和基础制备工艺研制、中试制备技术研发、工业放大试生产、固定床和搅拌釜浆态床评价研究等,开发出了神华具有"主-次双活性中心"结构的低温浆态床费托合成工业沉淀铁系催化剂SFT418,并在CEU中试装置上按工业化煤基浆态床费托合成油工艺对催化剂进行了试验。通过工业生产催化剂SFT418-7长周期运转,优化了催化剂工业应用的工艺条件,获得了有关物料平衡数据、产品分布和性质等数据。研究表明开发的新型催化剂SFT418在工业条件下:CO总转化率>92%,C5+占烃类产率>93mol%,性能先进具备工业应用的条件。

鼓泡淤浆反应器甲醇合成热模试验的工程问题

介绍了鼓泡淤浆反应器甲醇合成热模试验的主要情况 ,并分析了热模试验中出现的工程问题 .保持催化剂高活性是三相床甲醇合成新工艺开发成功的关键 ;催化剂的流化。

Fischer-Tropsch reaction within zeolite crystals for selective formation of gasoline-ranged hydrocarbons

Product selectivity control is attractive in Fischer-Tropsch(F-T)synthesis but it is still a challenge,because the F-T products follow the Anderson-Schulz-Flory(ASF)distribution with maximized gasoline-ranged(C_(5)-C_(11))hydrocarbon selectivity at 45%.Herein,we report a strategy by optimizing the gasoline selectivity to outperform the ASF limitation.The key to this success is fixation of the metal nanoparticles within zeolite crystals(metal@zeolite),where the zeolite micropore adjusts the product selectivity.For example,the Ru@NaY exhibited the gasoline selectivity 64.3% in the F-T reaction,which is significantly higher than the ASF limitation and about 2 times of that(32.8%)over conventionally supported Ru catalyst(Ru/NaY).This investigation might offer an alternative route for the direct transformation of syngas to liquid fuels with controllable selectivities.

Bridging complexes of rare earth and cobalt cluster as catalyst precursors for Fischer-Tropsch synthesis

Three new bridging complexes of rare earth and cobalt cluster were synthesized and characterized via ICP, IR and TG techniques. The structure of the complexes was speculated as： two rare earth atoms were bridged with four CF3COO–, and rare earth atoms were coordinated with cobalt carbonyl clusters to form a steady structure. Application of the complexes as the catalyst precursors was explored for Fischer-Tropsch synthesis. The study showed that the bridging complexes of rare earth and cobalt cluster had large molecular size and were difficult to enter pore path of γ-Al2O3, so they were dispersed on the surface of γ-Al2O3 support. In addition, the performance of Co（Ce）/ γ-Al2O3 was the best among the catalysts with complex as precursor and maintained 77.7% CO conversion at 220 oC for 80 operation hours.

Thermodynamics fundamentals and energy efciency for the separation and high‑valued utilization of Fischer–Tropsch heavy oil

The development trend of Fischer–Tropsch(F–T)technology is to develop high value-added products.The separation of linearα-olefns with low cost is an efective method.Nevertheless,the lack of thermodynamic data and the huge energy consumption are the two main problems restricting the development of the separation process.The thermodynamic data of the key components(1-dodecene and n-dodecane)in the F–T product were measured.The Wilson binary interaction parameters of the key components were obtained.Next,one traditional distillation column sequence and two dividing wall column(DWC)sequences were designed to separate the F–T heavy oil to obtain narrow fractions with diferent carbon numbers.Then,the obtained fractions of C10 and C12 were simulated to obtain 1-decene and 1-dodecene,respectively.There was a traditional distillation and a diferential pressure thermal coupling distillation process.When separating 95.0%purity 1-decene and 1-octene,the direct DWC process and diferential pressure thermal coupled distillation are an excellent combination,which can reduce the energy by 33.1%(i.e.,11,286 kW)and total annual cost by 15.9%(i.e.,3.96×10^(6)$)compared with traditional distillation.