苯对甲苯歧化与烷基转移反应的影响

研究了原料中苯含量对甲苯歧化与烷基转移反应的影响。随着原料中苯含量的增加 ,甲苯歧化反应受到明显抑制 ,同时发生苯和C9芳烃之间的烷基转移反应 ,C9芳烃转化率和C8芳烃选择性明显升高 ,有利于歧化装置多产C8芳烃。     

HAT-095催化剂运行末期的优化探索

通过优化工艺条件,严控进料质量、改造循环氢压缩机油系统、调整二甲苯塔操作等措施,使催化剂在运行末期,也能发挥出良好的催化性能,并延长催化剂使用寿命;提高了催化剂处理C10芳烃的能力,降低重芳烃产率,提高经济效益。为催化剂运行末期操作和正常操作提供有益的探索。     

吡啶型铝酸盐离子液体催化β-甲基萘歧化反应

研究了三氯化铝-氯化丁基吡啶(n-BPC-AlCl3)离子液体催化β-甲基萘歧化合成2，6-二甲基萘(2，6-DMN)反应。通过正交试验，考察了反应温度、时间、BPC—AlCl3离子液体酸强度及催化剂用量对β-甲基萘歧化反应的影响。实验结果表明，BPC—AlCl3酸性离子液体对β-甲基萘歧化反应具有良好的催化活性和较好的2，6-二甲基萘选择性。在120℃，AlCl3／BPC的摩尔比为4：1，催化剂质量分数12％，反应时间为3．5h的条件下，反应转化率为29．0％，2，6-DMN的选择性为32．5％。     

Kinetics of methylamine conversion on a Pd catalyst in the presence of H2

The kinetics of disproportionation of methylamine to dimethylamine and ammonia in the presence of hydrogen have been investigated over a silica-supported palladium catalyst. At a fixed partial pressure of methylamine, the reaction rate generally increases with decreasing hydrogen partial pressure, approaching a limiting or maximum value at sufficiently low pressures of hydrogen. The existence of a maximum is supported by the observation that the presence of some hydrogen appears to be necessary for the reaction to proceed at a conveniently measurable rate. At a fixed hydrogen partial pressure, the reaction rate increases with increasing methylamine partial pressure. When the methylamine partial pressure is sufficiently low or the hydrogen partial pressure is sufficiently high, the reaction order with respect to methylamine can be somewhat higher than one. At such conditions, a mechanism involving a bimolecular reaction between two partially dehydrogenated methylamine molecules on the surface appears to make a significant contribution to the overall catalytic reaction.     

甲苯歧化与C9芳烃烷基转移反应动力学模型和模拟分析

A new kinetic model for commercial unit of toluene disproportionation and C9-armatiocs transalkylation is developed based on the reported reaction scheme.A time based catalyst deactivation function taking weight hourly space velocity（WHSV）into account is incorporated into the model,which reasonably accounts for the loss in activity because of coke deposition on the surface of catalyst during long-term operation.The kinetic parameters are benchmarked with several sets of balanced plant data and estimated by the differential variable metric optimiza- tion method.Sets of plant data at different operating conditions are applied to make sure validation of the model and the results show a good agreement between the model predictions and plant observations.The simulation analysis of key variables such as temperature and WHSV affecting process performance is discussed in detail,giving the guidance to select suitable operating conditions.     

Dehydrocyclization of 1-hexene to benzene on Cu3Pt(111)

The disproportionation ofn-butane (and of isobutane) was catalyzed by sulfated zirconium oxide containing 1.5 wt% Fe, 0.5 wt% Mn, and 4.0 wt% sulfate at 2.0 atm and temperatures in the range of 30–60C. The reaction accompanies isomerization, which under some conditions is as much as one or two orders of magnitude faster than disproportionation. The conversion to each of the products increased with time on stream in a flow reactor, and then declined. The time on stream for maximum conversion was the same for each product. The results suggest that the disproportionation and isomerization reactions proceed through a common C₈ intermediate. Rates of the disproportionation reaction were determined at the time on stream corresponding to the maximum conversion at each temperature; for example, the rate of conversion ofn-butane into isopentane at 60C with ann-butane partial pressure of 0.58 atm was about 1×10^–7 mol/(g of catalyst s).     

HAT-097B甲苯歧化催化剂反应性能的研究

研究了以β沸石为主体的HAT-097B催化剂在催化甲苯和C₉芳烃歧化与烷基转移反应中，反应空速、温度及原料中C₁₀芳烃含量对反应性能的影响。结果表明，该催化剂在重量空速2.5h^-1，反应温度380℃时反应转化率高达47%，并可使用C₁₀芳烃含量达8%的反应原料，可综合利用芳烃资源，具有良好的工业化前景。     

废水的反歧化生物脱氮技术研究进展

自荷兰学者Strous等在反硝化过程中发现了生物反歧化脱氮(厌氧氨氧化)现象之后,该技术在近十余年中已经成为废水脱氮领域的研究热点问题之一.并由于低廉的运行成本和快速的脱氮效率,而使其在高氨氮废水脱氮领域中具有广阔的应用前景.本文总结了生物反歧化脱氮技术的研究与应用发展过程,并对该技术的实际工程运用前景进行了展望.     

Electrical properties of La0.6Sr0.4Co1-yFeyO3 cathode material

The electrical properties of La0.6Sr0.4Co1-yFeyO3 （LSCF, y=0-1.0） cathode materials were measured by DC four probes, X-ray photo-electron spectrum （XPS） was also introduced to determine the chemical state of Co, F.e ions in LSCF. It is found that the electrical conductivity of each sample has a maximum value with increasing temperature. XPS analysis shows that Co ion has three different chemical states, corresponding to two with Fe ion. The analyses indicates that the small-polaron hopping mechanism dominates the electron conduction at low temperature, while at high temperature, the three factors such as the thermally activated disproportionation of Co^3＋ ions into Co^2＋ and Co^4＋ pairs, the ionic compensation of oxygen vacancies formed at high temperatures, and Fe^4＋ ions charge compensation preferential to Co^4＋, all contribute to electrical conduction.     

Mechanically activated disproportionation of NdFeB alloy by ball milling in hydrogen

1　INTRODUCTIONSincethediscoveryoftheuniaxialNd2 Fe14 Bcompoundin 1983[1,2 ] ,theNdFeBalloyshavebeenwidelyusedforpermanentmagnetapplicationsowingtotheirexcellentmagneticproperties ,suchashighcoercivity ,high energy products[3,4 ] .Intheserareearthpermanentmagnets ,afurtherexcitingrecentdevelopmentisthesuggestionofnano compositeex changemagnetscombiningthelargecoercivitiesinhardmagnetswithlargeinductionsfoundinsoftertransitionmetalmagnets[5,6 ] .Indeed ,thenano com positemagnetshavebeent…