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排序方式: 共有511条查询结果,搜索用时 31 毫秒
31.
综述了催化油浆利用技术方面的研究进展,包括炼油装置掺炼,生产道路沥青、针状焦、炭黑,作为橡胶软化剂和填充油等,对催化油浆的综合利用前景进行了展望。 相似文献
32.
33.
芳胺类抗氧剂与ZDDP复合抗氧效果的研究 总被引:4,自引:0,他引:4
在研制同档汽油过程中,对芳胺类抗氧剂苯基-α萘胺与ZDDP复合抗氧效果进行考查,分析表明,苯基-α萘胺的配伍性及抗氧能力较好。 相似文献
34.
Based on our comprehensive theoretical investigation and known experimental results for small boron clusters, we predict the
existence of a novel aromatic inorganic molecule, B12H6. This molecule, which we refer to as borozene, has remarkably similar properties to the well-known benzene. Borozene is planar, possesses a large first excitation energy,
D
3h symmetry, and more importantly is aromatic. Furthermore, the calculated anisotropy of the magnetic susceptibility of borozene
is three times larger in absolute value than for benzene. Finally, we show that borozene molecules may be fused together to
give larger aromatic compounds with even larger anisotropic susceptibilities. 相似文献
35.
Shigeru Kohtani Eito Yoshioka Kenji Saito Akihiko Kudo Hideto Miyabe 《Catalysis communications》2010,11(13):1049-1053
In the absence of molecular oxygen, various aromatic ketones such as acetophenone derivatives and diaryl ketones were photocatalytically hydrogenated on polycrystalline titanium dioxide (Degussa P25) under UV light irradiation (> 340 nm). The desired secondary alcohols were obtained with excellent chemical efficiency (almost 100% yields for 10 examples) by choosing ethanol as a sacrificial hole scavenger, which was oxidized into acetaldehyde. 相似文献
36.
Solvent extraction is a practical method for the reduction of lube oil aromatic content. Common solvents are phenol, furfural, and N-methyl pyrrolidone (NMP). The extractive power and the selectivity parameters can be increased by the addition of surfactants, which facilitates phase separation and consequently increases the refinery yield. The operatory extraction temperatures and surfactant concentrations ranged, respectively, from 333.15 to 343.15 K and from 0.01 to 0.1%wt. Optimal extraction conditions were systematically determined by measuring the temperatures and surfactant concentrations. The amounts of aromatic, paraffinic, and naphthenic compounds were compared to ASTM standards, namely refractive index (RI), viscosity, molecular weight, and sulfur content. The experimental results show that the best results were realized with 0.01%wt of surfactant and at 343.15 K. 相似文献
37.
The effects of sonication time, nitrogen, N2(g), increasing temperature, dissolved oxygen (DO) and titanium dioxide (TiO2) concentrations on the sonodegradation of polyaromatic hydrocarbons (PAHs) in petrochemical wastewaters were investigated. Sonication alone without N2(g), DO and TiO2 provided 80% maximum PAH yields at 2 5°C after 150 min. This PAH yield increased to 89–95% at 60 °C after 150 min sonication. The contribution of DO, N2(g) and TiO2 on the PAH removal was not significant compared to the control. In the presence of HCO3 ?, the degradation of hydrophobic PAH dibenz[a,h]anthracene (DahA)was suppressed in the acceleration step of the sonication. Maximum acute toxicity removal was reached by 30 min N2(g) sparging, 4 mg/L DO and by 0.1 mg/L TiO2 after 150 min sonication. 相似文献
38.
The retention mechanism of solutes under gradient conditions has been studied. Separation of a mixture of seven aromatic compounds
in the two binary mobile phase, water/methanol and water/acetonitrile, was considered as an example. Retention factors were
experimentally correlated by mobile phase composition. In this work, gradientdeviation time was newly introduced to compensate
for ideal steep band along a column and experimentally determined by a linear equation form. An analytical expression in terms
of the calculated retention factor and peak width was presented to predict the elution profile under gradient conditions.
The calculated elution profile considered by the gradient-deviation time was closer to experimental data, and this mathematical
model showed the feasibility of a predictive tool under gradient conditions. 相似文献
39.
介绍了ZSM - 5沸石及其改性催化剂用于低碳烯烃C2 =~C5=的芳构化性能 ,结果表明在ZSM - 5沸石中加入一些金属如Zn、Ga、Pt、Ni、Cd等得到的改性催化剂可直接将烯烃及其混合物转化为芳烃 ,且芳烃收率、选择性都大有改善。各种金属及其引入方式对烯烃芳构化的影响不一样 ,催化剂的制备方法中 ,以离子交换法最佳 ,其次是浸渍法 ,最后是混合法。金属的引入量有最佳值 ,如ω(Cd)≤ 0 .8%时效果最佳。此外对各种操作条件如反应温度、空速、载气等方面进行了论述 ,认为反应温度以 35 0~ 5 5 0℃为宜 ,空速不能太大 ,以H2 为载气比N2 为载气好。探讨了烯烃芳构化的反应机理 ,并对其工艺用于烯烃汽油改质的工业应用前景作了预测 相似文献
40.
Liu Yansheng Zhang Zhongxin Zhang Guofu Liu Zhichang Hu Yufeng Shi Quan Ji Dejun 《石油科学(英文版)》2006,3(3):73-78
1. Introduction Benzene is a key chemical in the chemical industry, used as the raw material for producing polymer precursors, solvents, dyes, drugs, herbicides, and so on. The world production of benzene is more than 2.0×107 tons/year (Vervalin, 1991; Weissermel and Arpe, 1993; Villaluenga and Tabe-Mohammadi, 2000). Before World War II, benzene was mainly produced from coal, but nowadays more than 90% is obtained from petroleum, mainly from catalytic reformates and FCC gasoline, and by … 相似文献