RS-20重整预加氢精制催化剂的工业应用

将RS-20催化剂成功的应用于重整装置上,在低温、高空速下操作条件下,精制产品满足重整进料要求;RS-20催化剂用于处理直馏汽油,具有较高的反应活性,同其它重整预加氢催化剂相比,在相同的反应温度、氢分压、氢油比条件下,可以采用更高的空速,精制原料完全满足重整进料要求。     

还原空速对Fe/Cu/K/SiO2催化剂浆态床F-T合成性能的影响

在浆态床反应器中详细考察了合成气还原空速对微球状工业铁基催化剂还原和反应后的物相以及F-T合成反应性能的影响. 研究结果表明：空速能够影响铁基催化剂还原反应进程，催化剂在较高的空速下易被还原，还原后催化剂的比表面积降低，平均孔径增大. 在较低空速下还原时，还原形成的高的CO₂分压对铁物相有一定的氧化作用，使得还原态催化剂中的Fe³⁺(spm)含量增大. 还原空速对F-T合成烃产物分布影响不明显，但对催化剂的反应活性和运行稳定性影响较大，较低和较高空速还原后的催化剂失活速率均较高，适宜的还原空速为1.0～2.0 L•（g cat）^-1•h^-1.     

反应条件对MoP/TiO2-SiO2-Al2O3催化剂加氢脱氮性能的影响

用溶胶凝胶法制备了不同TiO2含量的MoP/TiO2-SiO2-Al2O3催化剂,对含喹啉的模型化合物,在连续固定床反应器上进行了HDN活性评价,考察了不同反应条件（反应温度、空速、压力、氢油比）对催化剂加氢脱氮性能的影响.结果表明：原位还原法制备的磷化钼催化剂,其加氢活性与原位还原条件有较大的关系,实验确立了最佳加氢脱氮的反应条件为：反应温度为380℃,空速为2.0h^-1,压力为3.0MPa,氢油比为500.     

还原工艺对费托合成铁基催化剂反应性能的影响

为获得还原参数对铁基费托合成反应性能的影响规律,利用铁基催化剂,在固定床反应器中考察还原氢碳比、温度、空速和压力对催化剂物理性能以及费托合成反应性能的影响。结果表明,在不同的还原工艺下,还原后的铁基催化剂比表面积下降,平均孔径增大;还原氢碳比和还原压力的升高抑制了催化剂的活性,CH_4和CO_2的选择性及C_2~C_4含量升高,C_(5+)含量下降,烃分布向轻质烃分布;还原温度和还原空速的增加有利于提高催化剂活性,还原温度的提高促使烃分布向轻质烃分布,还原空速的提高对产品分布影响不大。     

CO2加氢和Cu-Zn-O催化剂的特性 Ⅱ.Cu-Zn-O催化剂处理条件和反应条件的研究

本文研究了催化剂焙烧条件,还原过程因素（还原气组成、升温速率和还原气空速）,催化剂制备方法及反应温度、压力、H₂/CO₂进料比、空速和催化剂的热橄定性。探讨了Cu-Zn-O催化剂各组成的功能 并弄清了催化剂的反应特性,获得了最佳操作条件。     

非临氢条件下甘油氢解制1,2-丙二醇的研究

综述了非临氢条件下甘油氢解制1,2-丙二醇的研究进展,介绍了目前甘油原位加氢的2种途径(甘油液相重整加氢和甘油催化转移氢化反应)及优缺点,并对可能的甘油氢解机理进行了阐述。目前采用贵金属催化剂Pt/HT和Pd/Fe_2O_3以及非贵金属Cu/ZrO_2、复合金属Cu-Ni/Al_2O_3均能获得较高的1,2-丙二醇选择性(80%)。最后对非临氢条件下甘油原位加氢的研究工作进行了总结,并对未来研究方向做出展望。     

还原条件对高温费托合成熔铁催化剂性能的影响

为了探索熔铁催化剂还原过程中物相变化及对高温费托反应性能的影响，采用SEM（扫描电子显微镜）、EDS（X射线能谱仪）、BET和原位XRD（X射线衍射）对催化剂进行了表征。并在类似工业条件（340℃、2.4MPa、H₂/CO比例为3.8）下，于固定床反应器上评价了费托反应性能。分析了不同升温过程、氢气分压、还原空速和还原时间对高温费托熔铁催化剂物相结构、晶粒尺寸、还原度等的影响。结果表明：起始升温速率影响显著，＞2.4℃/min时容易使催化剂局部温度过高进而还原速率过快，导致α-Fe晶粒快速长大并团聚。氢气分压影响还原度有转折点，＞70%时还原度变化趋势相同；对α-Fe晶粒尺寸的影响表现在低氢分压时更稳定，40h内40%H₂/Ar条件仅增加1nm。高还原空速（10000h^-1）使得还原催化剂表面孔道分布、孔径尺寸更均匀，还原效率及极限还原度更高；而低还原空速（1000~2000h^-1）则使得还原催化剂表/体相结构稳定，晶粒尺寸更稳定，费托合成反应活性高。还原时间在其他条件固定下有最佳值，420℃恒温还原到极限还原度后，α-Fe晶粒尺寸随还原时间延长继续缓慢增长。通过研究获得了适宜的还原条件为：还原升温速率0.4℃/min（200~350℃）~0.8℃/min（＜200℃），空速5000h^-1，还原时间＜30h。     

Cu-Zn-Al-Zr催化剂上CO_2加氢合成甲醇的性能研究

采用并流共沉淀法制备了Cu-Zn-Al-Zr催化剂,利用N_2吸附脱附、XRD进行了催化剂的表征,考察了反应温度、压力及空速对催化剂性能的影响。结果表明,Cu-Zn-Al-Zr催化剂为介孔材料,平均孔径14.29 nm;还原后催化剂上的CuO被还原为金属Cu0;低温度、低空速及高压有利于CO_2加氢合成甲醇的反应。     

Co(OH)_2碱性浆化氢还原制备超细Co粉

首次实现了Co(OH)2浆料在碱性介质中的氢还原反应, 并由此制得了粒度小于0.1μm的超细金属钴粉. 还原终点的pH为8～12, 反应一般可在30～60 min内完成, Co的金属转化率接近100%. 考察了pH、温度、氢分压、催化剂等对还原速度的影响,并与Ni (OH)2碱性水浆的氢还原作了简单比较.     

Co(OH)2碱性浆化氢还原制备超细Co粉

首次实现了Co(OH)2浆料在碱性介质中的氢还原反应, 并由此制得了粒度小于0.1μm的超细金属钴粉. 还原终点的pH为8~12, 反应一般可在30~60 min内完成, Co的金属转化率接近100%. 考察了pH、温度、氢分压、催化剂等对还原速度的影响,并与Ni (OH)2碱性水浆的氢还原作了简单比较.     

过渡金属氧化物催化剂上水煤气还原冶炼烟气中SO_2

采用浸渍法制备出系列过渡金属氧化物催化剂(Cu、Co、Fe和Ni),以模拟水煤气和模拟冶炼烟气为原料气,考察了活性组分、温度、空速、气配比和预硫化处理等对SO_2转化率和硫收率的影响。结果表明,Fe催化剂为最佳催化剂,SO_2转化率和硫收率均随温度的升高而增加,但温度过高,选择性变差,导致硫收率下降,最佳温度400℃;空速过大或过小均不利于反应进行,温度较高时,空速的影响较小,最佳空速3 000 h~(-1);气配比对反应的影响较大,SO_2烟气与水煤气体积比应控制在1.7左右。研究表明,金属硫化物是催化SO_2还原的活性相,反应机理应为中间产物机理。     

H2S oxidation by multi-wall carbon nanotubes decorated with tungsten sulfide

Tungsten sulfide catalysts decorated on single and multiwall carbon nanotubes (SWNTs & MWNTs) and activated carbon were synthesized, and XRD, ICP, SEM, TEM and ASAP analyses were employed to acquire the characteristics of each catalyst. Afterwards a gas flow containing 5,000 ppm of H₂S was passed over the catalyst in gas hour space velocity (GHSV) of 5,000 h^?1, temperature of 65 °C, steam volume percent of 20 and O₂/H₂S ratio equal to 2. The results revealed that the catalyst supported on MWNTs exhibited higher conversion amongst its counterparts. Then effects of GHSV, steam volume percent in the feed, catalyst loading and temperature were investigated on conversion of hydrogen sulfide to elemental sulfur for tungsten sulfide catalyst decorated on MWNTs.     

Catalytic performance and characterization of cobalt-nickel nano catalysts for CO hydrogenation

A series of Co-Ni nano catalysts were prepared by co-precipitation method. We investigated the effect of Co/Ni molar ratios precipitate and calcination conditions on the catalytic performance of cobalt nickel catalysts for Fisher-Tropsch synthesis (FTS). The catalyst containing 90%Co/10%Ni was found to be optimal for the conversion of synthesis gas to light olefins. The activity and selectivity of the optimal catalyst were studied in different operational conditions. The results show that the best operational conditions are the H₂/CO=2/1 molar feed ratio at 310 °C and GHSV=1,200 h^?1 under 5 bar of pressure. The prepared catalysts were characterized by powder X-ray diffraction (XRD), N2 adsorption-desorption measurements such as BET and BJH methods, transmission electron microscopy (TEM) and thermal gravimetric analysis (TGA).     

Catalyst Preparation Using Supercritical Carbon Dioxide: Preparation of Rh/FSM-16 Catalysts and Their Catalytic Performances in Butane Hydrogenolysis Reaction

Supported Rh catalysts on FSM-16 were prepared by treating FSM-16, impregnated with [Rh(OAc)₂]₂ in supercritical carbon dioxide at 398 K and 30.3 MPa, followed by calcination and hydrogen reduction. The resulting Rh/FSM-16 catalysts were characterized by CO chemisorption, XRD, TEM, FTIR and EXAFS, and catalytic performances of the Rh/FSM-16 were tested in butane hydrogenolysis reaction. It is demonstrated that highly dispersed Rh particles are obtained by the supercritical CO₂ treatment. In the hydrogenolysis reactions, the supercritical CO₂-treated catalyst showed higher conversions and ethane formation.     

n-Octane aromatization on Pt-containing non-acidic large pore zeolite catalysts

Platinum catalysts supported on the potassium-form of different large-pore zeolites (i.e. K-LTL, K-BEA, K-MAZ, and K-FAU) have been tested for n-octane aromatization at 500 °C. All catalysts were prepared by the vapor phase impregnation (VPI) method. It was found that the Pt/K-LTL catalyst exhibit a better aromatization performance than the other zeolite catalysts. However, due to secondary hydrogenolysis, the C8 aromatics produced inside the zeolite are converted to benzene and toluene. By contrast, a non-microporous Pt/SiO₂ catalyst did not present the secondary hydrogenolysis. Therefore, despite a lower initial aromatization activity, Pt/SiO₂ results in higher selectivity to C8 aromatics than any of the other zeolite catalysts. All fresh catalysts were characterized by hydrogen chemisorption and FT-IR of adsorbed CO. In addition, the residual acidity of the supports was analyzed by temperature programmed desorption (TPD) of ammonia. In agreement with previous studies, it was found that after reduction at either 350 or 500 °C, the Pt/K-LTL showed much higher Pt dispersion than other catalysts. It is known that the structure of L zeolite can stabilize the small Pt clusters inside the zeolite channel. By contrast, FT-IR indicated that a large fraction of platinum clusters were located outside the zeolite channels in the case of Pt/K-BEA and Pt/K-MAZ catalysts.     

苯甲酸催化加氢制备无氯苯甲醛的中试

运用共沉淀法制备了锌锰复合纳米催化剂,并用于气相催化加氢苯甲酸合成无氯苯甲醛。单管小试及多管扩大中试表明,该催化剂不但具有很高的催化选择性,同时在较低温度下仍保持很高的活性。多管扩大最佳实验条件为:反应温度370±5℃,催化剂预还原时间50 h,氢气压力1.4×105~1.6×105Pa,氢酸分压比40∶1~50∶1,氢气气时空速650~750 h-1时,苯甲酸的转化率高达99%,苯甲醛的选择性为83%。     

器外预硫化加氢催化剂的研究

不同的硫化剂与催化剂混合制备器外预硫化加氢催化剂,以考察催化剂的集中放热现象和集中耗氢现象。结果表明:200℃左右氮气氛围的条件下催化剂中的活性组分与硫化剂结合生成有机氧硫化物。适当比例混合的硫化剂与催化剂制成的器外预硫化催化剂,能有效的缓解集中放热和集中耗氢现象;有效的避免了床层飞温和氢气压力骤降问题。并且制成的器外预硫化催化剂拥有很高的持硫率和活性。     

铜基催化剂还原过程研究综述

铜基催化剂广泛应用于工业生产中,催化剂还原是催化剂生产的最后一道工序,也是工业使用前的第一个步骤,对几种铜基催化剂的还原过程进行综述。铜基催化剂主要应用于CO与H_2合成甲醇和CO低温变换,也可用于CO_2与H_2合成甲醇以及脂肪酯加氢制脂肪醇。铜基催化剂的还原方法主要有液相还原法和气相还原法,其中,气相还原法用途较广。对影响还原的条件(H_2浓度、温度、压力和空速等)及杂质(H_2O、O_2和CO_2等)进行总结,并以甲醇合成催化剂为例对低氢还原法和高氢还原法作了介绍。     

Effect of preparation method on structure and catalytic activity of Cr-promoted Cu catalyst in glycerol hydrogenolysis

Relationships between surface structure and catalytic properties were investigated for a series of copper chromium catalysts. The catalysts were prepared using methods involving impregnation and precipitation, and their catalytic activities were evaluated for the hydrogenolysis of glycerol. Catalyst (10I and 50I) prepared by the impregnation method contained a mixed phase of both individual copper and chromium oxide structures, while the catalyst (50P) prepared by precipitation showed a single phase, with a copper chromite spinel structure (CuCr₂O₄). XPS data indicated that, after the reduction step, the copper species in the impregnated catalyst was reduced to Cu⁰, but the catalyst prepared by the precipitation method retained a spinel structure evidenced by the large amount of Cu²⁺ species. In hydrogenolysis reactions, the precipitated catalyst showed a higher catalytic activity than the impregnated catalyst. Thus, the reduced copper chromite spinel structure, which constitutes a single phase, appears to be responsible for the high catalytic activity in the hydrogenolysis of glycerol to propylene glycol.     

Conversion of CCl2F2 (CFC-12) in the presence and absence of H2 on sol–gel derived Pd/Al2O3 catalysts

Conversion of CCl₂F₂ in the presence (hydrogenolysis) and absence of hydrogen was investigated on Al₂O₃, AlF₃ and Pd/Al₂O₃ xerogel and aerogel catalysts. CCl₂F₂ was found to form CClF₃ and CCl₃F on Al₂O₃ and AlF₃ in the presence and absence of hydrogen as well as on the Pd/Al₂O₃ catalysts in the absence of hydrogen. Overall activity increased during the hydrogenolysis reactions at 230°C as a function of time which was paralleled by a significant increase in the yield of CClF₃ formed through a Cl/F-exchange reaction. X-ray diffraction patterns of the spent catalyst recovered after 3 h of hydrogenolysis confirmed the presence of Pd(C) (Pd–carbon solid solution) and AlF₃ phases on Pd/Al₂O₃ catalysts indicated that the carbon incorporation into the Pd lattice and the transformation of Al₂O₃ to AlF₃ starts at the initial stage of the reaction. It was concluded that AlF₃ is responsible for the Cl/F-exchange reactions. CH₄, a complete hydrogenation product, is formed during hydrogenolysis. Another route for its formation is the reaction between hydrogen in the gas phase and the interstitial carbon.