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141.
石油馏份油加氢精制的核心是馏份油的加氢脱硫(HDS)和加氢脱氮(HDN)。目前用于基础研究与工业过程的加氢精制催化剂主要是负载型过渡金属硫化物[Co(Ni)Mo(W)/γ-AI2O3]^[1,2]。近年来的研究结果表明,在活性相中引入其它适宜种类的助剂组元有助于催化剂活性及产物选择性的改善^[3,4]。本文以Keggin型钼磷酸为硫化物前体活性相钼磷源、硝酸镍为镍源制成不同钼含量的负载型硫化态三组元催化剂(NiMoP/γ-AI2O3),并在TPR及连续流动固定床反应装置上考察了催化剂的氢还原性能及模型底物噻吩HDS反应活性。 相似文献
142.
硫化态三组元NiMoP/γ-Al2O3催化剂的TPR表征及噻吩HDS活性的研究 总被引:1,自引:0,他引:1
A series of sulfided tertiary NiMoP/γ-Al2O3 catalysts with different contents of MoO3 were prepared by using molybdophosphoric acid of Keggin structure(H3PMo12O40) and nickel nitrate as origins of active phase components of molybdenum, phosphorus and nickel, and characterized by TPR technique, with their HDS activity being investigated with thiophene as a model substrate. For the sulfided Mo-0 catalyst containing no nickel as promoter, the only hydrogen sulfide evolution peak Ⅰ is observed at 462 K and attributed to the hydrogenation of the so-called edge sulfur atoms chemisorbed on coordinatively unsaturated(cus) Mox+ sites on the MoS2 phase(MoS2 slab). With the introduction of nickel into the active phase of the sulfided Mo-0 catalyst and with the increase of the molybdenum loading, a new hydrogen sulfide evolution peak Ⅱ gradually develops at the low temperature side of the peak Ⅰ, at the same time accompanied by both the increase of the area ratio of the peak Ⅱ to the peak Ⅰ and the shift of the hydrogen sulfide evolution maximum rate to lower temperatures, which may imply the existence of two kinds of active centers related to molybdenum and nickel respectively and the synergic action between the two centers above. It should be noted that for the sulfided NiMoP/γ-Al2O3 catalysts, the thiophene HDS rate and the quantity of hydrogen sulfide evolved during TPR process increase monotonously with the atomic ratio of molybdenum to nickel in the form of [n(Ni)+n(Mo)]/n(Ni). On the basis of the results here, the conclusion may be reached that the two kinds of vacancies can be formed on the edge of Ni-Mo-S slab due to the loss of S during TPR process and vacancies or sites related to the H2S evolution peak II should be regarded as the mainly active reaction centers of thiophene HDS. 相似文献
143.
Pt/γ-Al2O3催化剂活性位的表征及其噻吩加氢脱硫催化活性 总被引:2,自引:0,他引:2
A series of Pt/γ Al 2O 3 catalysts with different content of Pt were characterized by using low temperature FT IR spectroscopy of adsorbed CO, while their catalytic activity for HDS was investigated with thiophene as a model substrate. On the basis of the experimental results, it has been obtained that the pseudo zero order rate of the thiophene HDS reaction is well linearly proportional to the total area of the two IR bands at 2?080 and 1?850 cm -1 of CO adsorbed on Pt/γ Al 2O 3, and that the Pt sites for CO adsorption may be the active centers for thiophene HDS reaction. 相似文献
144.
We propose a simple experimental scheme in which an unknown two-qubit state
is faithfully and deterministically teleported from Alice to Bob. The scheme
is constructed with four photons from parametric down conversion, linear
optical elements, and conventional photon detectors, all of which are
available in current technology. It is shown that the probability of
successful teleportation ideally reaches 100% based on single-photon
two-qubit-assisted Bell-state measurement, which can distinguish all
four Bell-states simultaneously via conventional photon detectors. By
generalizing the scheme, the teleportation of an unknown multi-qubit system
can also be realized. 相似文献
145.
The effects of trapped electrons on off-axis lower hybrid current drive (LHCD) in tokamaks are studied, A computer code for solving the Fokker-Planck equation in a toroidal geometry is developed and employed. The code is suitable for various auxiliary heating and current drive schemes in tokamak plasmas. The influence of the resonance regime on the current drive efficiency as well as the influence of trapped particle fraction on the current drive efficiency are emphasized. It is shown that, as an electrostatic force, the lower hybrid wave causes some of the trapped electrons to be untrapped and lose their energy, which can cut the LHCD efficiency by about 30%. The ITER scaling law is also used to estimate the trapped electron effects.[第一段] 相似文献
146.
本文采用静态水热合成法合成了一种非水溶性固体铜铝磷酸盐(CuAlPO).研究结果发现,CuAlPO是一种与六方二氧化硅(SiO2)晶体结构相同的新型铜铝磷盐,在温和反应条件下(30℃),CuAlPO具有较高的苯酚催化羟化反应活性. 相似文献
147.
148.
基于有限体积法和米氏方程,本文研究了一维和二维平板气升式反应器内,入射光分别为平行光和漫射光时,反应器内藻类密度以及气泡体积率对反应器内投射辐射力分布和制氢率的影响。研究发现,当反应器内只有藻类且吸收占优时,平行光入射时投射辐射力近似按Beer定律衰减,衰减率小于漫射光。当有气泡存在时,平行光入射条件下投射辐射力衰减不能简单按Beer定律考虑,尤其是当反照率较大时。同时,在平行光入射反应器的情况下,反应器内藻类制氢率大且有效光合作用区大,更有利于藻类制氢。 相似文献
149.
评价膜-基体系的综合性能的重要指标是其失效的临界载荷。膜-基体系的失效不仅发生在界面,也有可能发生在镀层或底材之中,或许还有可能发生混合失效,因此,在测试膜-基低系失效的临界载荷方面,即使是已经在国内外得到广泛应用的划痕法也有其弱点,为了使膜-基体系的失效临界载荷的测试尽可能地接近于实际使用工况,更能切近实际地反映膜-基体系的综合承载能力,提出了一种擦膜试验法,并且研制了CM-1型多功能擦膜摩擦试 相似文献
150.
对(Cu-43Ni),(Cu-43Ni)/TiN和(Cu-43Ni)/NiP这3种摩擦副产生的热电势信呈作了频谱分析,并对三者进行了施加不同特性的交变电势信号的摩擦试验。结果表明,将交变电势旋加于3种摩擦副的均可降低摩擦力,降低程度与所加电势的幅值、波形及频率特性有关。 相似文献