Effect of Lanthanum on Performance of RuB Amorphous Alloy Catalyst for Benzene Selective Hydrogenation

The effect of La on the performance of a supported RuB amorphous alloy catalyst for benzene selective hydrogenation was studied by means of activity and selectivity tests, such as HRTEM, SAED, XPS, and XRD. The results show that the addition of La to RuB amorphous alloy catalyst can evidently increase the activity and improve the thermal stability of RuB amorphous alloy to refrain its crystallization. The promoting effect of La on the activity of RuB amorphous alloy catalyst is because of the high dispersion of the active components.

Effects of Cerium Dopant on Ni-B Amorphous Alloy Catalysts Used in 2-Ethylanthraquinone Hydrogenation

A series of Ce-doped Ni-B amorphous alloy catalysts were prepared by a KBH_4 reduction method, characterized by ICP, BET, XRD, H_2-chemisorption, H_2-TPD, etc., and tested in the hydrogenation of 2-ethylanthraquinone. The results of characterization show that with the addition of Ce the amount of H_2-chemisorption and H_2-TPD areas first increases markedly and then decreases with the maximum appears at the atomic ratio of Ce to Ni of 0.036. The hydrogenation activity also shows the same trend. The effects of Ce are attributed to its dispersion of Ni particles, resulting in the formation of more surface Ni centers. However, much higher Ce contents may result in the decrease of the surface Ni contents. After heat treatment at higher temperatures, the amorphous structure of Ni-B is destroyed.

Preparation of Uniform Ni-B Amorphous Alloy Catalyst on CNTs and its Performance for Acetylene Selective Hydrogenation

Uniform Ni-B amorphous alloys about 14 nm have been prepared on CNTs-A support,named Ni-B/CNTs-A. In comparison with the Ni-B/CNTs amorphous catalyst, Ni-B/CNTs-A showed higher nickel loading, determined by ICP and better catalytic activity and ethylene selectivity in the acetylene hydrogenation reaction.

A Pd-Fe-B/γ-Al2O3 Amorphous Alloy Catalyst for Hydrogenation of Chloronitrobenzene to Chloroaniline

A Pd-Fe-B/γ-Al2O3 amorphous alloy catalyst was prepared by impregnation and chemical reduction with borohydrine aqueous solution. The catalyst was characterized by X-ray diffraction（XRD）, scanning electron microscope（SEM）, differential scanning calorimetry（DSC） and elecdes design suite（EDS） and was used for catalytic hydrogenation of 5-nitro-2-chloro-2＇, 4＇-dimethylbenzenesulfonanilide （NCD）. The amorphous alloy catalyst shows significantly high activity and selectively for hydrogenation of NCD to 5-Amino-2-chloro- 2＇, 4＇-dimethyibenzenesuifonanilide （ACD）.

Magnetically stabilized bed reactor for selective hydrogenation of olefins in reformate with amorphous nickel alloy catalyst

A magnetically stabilized bed （MSB） reactor for selective hydrogenation of olefins in reformate was developed by combining the advantages of MSB and amorphous nickel alloy catalyst. The effects of operating conditions, such as temperature, pressure, liquid space velocity, hydrogen-to-oil ratio, and magnetic field intensity on the reaction were studied. A mathematical model of MSB reactor for hydrogenation of olefins in reformate was established. A reforming flow scheme with a post-hydrogenation MSB reactor was proposed. Finally, MSB hydrogenation was compared with clay treatment and conventional post-hydrogenation.

Effect of Metallic Additives on Structure and Catalytic Properties of Supported NiPB/SiO_2 Catalyst

A new preparation method was proposed to deposit amorphous alloys alloys containing NiPand metallic metallic additives such as Fe.Co. and Cu.The different effects of metallic additive onstructure and catalytic properties of supported amorphous NiMPB/SiO2 (M=Fe, Co. Cu) cafalysts were observed,and the improvement of catalytic activity due to heating pretreatment in hydrogenwas found.

Hydrogenation of phenylpyruvic acid to phenylalanine catalyzed by Ni-B/SiO_2

Phenylalanine （Phe） is a significant amino acid that cannot be synthesized by human themselves but must be taken from environment. It was initially found that the nanosized amorphous Ni-B/SiO2 alloy prepared by the chemical reduction method was an effective catalyst for the preparation of Phe from phenylpyruvic acid （PPA） by amination and hydrogenation. It has been found that the amorphous Ni-B/SiO2 alloy catalyst exhibits superior activity and selectivity to the traditional catalysts Raney Ni and Urushibara nickel. The effects of reaction time, amounts of catalysts and ammonia solution, reaction temperature, and H2 pressure on the reaction have been investigated systematically. The results indicated that the yield of Phe was 97.9%, and the selectivity for Phe reached 98.9% when the reaction was carried out for 3 h at 333 K and 2.0 MPa of H2 with m（Cat.） ： m（PPA） = 0.6 ： 1.0 and n（NH3） ： n（PPA） = 3 ： 1. The catalysts were characterized by XRD, AAS, XPS, BET, and TEM, and the relationship between the catalyst structure and the catalytic activity was discussed in detail. It was found that the reason why Ni-B/SiO2 amorphous alloy catalyst was much more active for the preparation of Phe could be accounted for by the presence of electron-rich Ni due to electron donation from alloying B; the smaller size of Ni-B particles, the larger specific surface area of Ni-B/SiO2.

Engineering electrophilic atomic Ir sites on CeO_(2) colloidal spheres for selectivity control in hydrogenation of α,β-unsaturated carbonyl compounds

Selective hydrogenation of the carbonyl bond inα,β-unsaturated carbonyl compounds is rather challenging owing to the more feasible hydrogenation of ethylenic bond from both thermodynamic and kinetic aspects.Here,we demonstrate a facile emulsionbased molecule-nanoparticle self-assembly strategy for the atomic engineering of Ir species on three-dimensional CeO_(2)spheres(Ir1@CeO_(2)).When applied to the hydrogenation ofα,β-unsaturated aldehydes,Ir1@CeO_(2)catalyst remarkably exhibited~100%selectivity towards unsaturated alcohols,whereas the formation of Ir nanoparticles on CeO_(2)drastically decreased the selectivity for unsaturated alcohols.Spectroscopic studies revealed that strong metal-support interactions triggered the charge transfer from Ir to CeO_(2),leading to the partial reduction of Ce^(4+)to Ce^(3+)along with the formation new Ir^(δ+)-O_(2)--Ce^(3+)(OV)interfaces.The electrophilic atomic Ir species at the Ir^(δ+)-O_(2)--Ce^(3+)(OV)interfaces would therefore preferentially adsorb and facilitate hydrogenation of polar C=O bond to achieve exceptional selectivity.

α,β-不饱和醛高选择性加氢研究进展

α,β-不饱和醛选择性加氢制备不饱和醇是一类具有挑战性的反应,是生产药品,香水和香料等有价值中间体的有效方法之一。对单金属非均相催化剂来讲,不饱和醇的形成在热力学上比饱和醛的形成更不利。因此,常需要高效的催化剂来达到高选择性。与单金属催化剂相比,双金属合金催化剂对不饱和醇的选择性显著提高。本文主要介绍了近年来关于α,β-不饱和醛在双金属合金催化剂上选择性加氢的研究进展。并主要综述了在不同金属表面的作用以及促进不饱和醛通过其C=O键吸附的因素,其中最明显的影响因素是通过表面的电子修饰作用和亲电性位点的形成。

非晶态合金催化剂用于葡萄糖加氢制山梨醇的研究

采用石油化工科学院研制的非晶态合金催化剂进行葡萄糖加氢，考察了温度、压力、ｐＨ 值、剂糖比和反应时间等因素对加氢反应的影响，并与其它Ｒａｎｅｙ Ｎｉ 类催化剂进行了对比。结果表明，使用ＳＲＮＡ－３ 非晶态合金催化剂进行葡萄糖加氢，当反应温度为１３０ ～１４０℃、压力为５ ～９ＭＰａ、ｐＨ值为８．３５、剂糖质量比为１％ 、反应时间为７０～１２０ｍｉｎ 时，转化率可达１００％ ，产品色度好。ＳＲＮＡ－３ 催化剂的葡萄糖加氢活性好于Ｒａｎｅｙ Ｎｉ 催化剂，重复使用时，也可保持较高活性。

非晶态合金Ru基催化剂在苯选择加氢中的应用进展

化学还原法制备的非晶态合金Ru基催化剂融合了纳米粒子和非晶态合金的结构特征,在苯选择加氢反应中表现出高活性和高环己烯选择性;尤其是负载型非晶态合金Ru基催化剂,具有贵金属利用率高和易于工业化等优点,有着明显的竞争优势.本文综述了苯选择加氢的热力学和动力学特征,非晶态合金催化剂结构和组成及其对催化性能的影响;总结了催化工艺条件、催化剂可调变性和中试成果,并展望了该技术的发展趋势.

镍基非晶态合金加氢催化剂与磁稳定床反应器的开发与工业应用

报道了开发镍基非晶态合金加氢催化剂的实验室研究、中试研究及工业应用研究结果。向非晶态合金中加入少量原子半径大的其他元素 ,使非晶态合金的晶化温度由 36 0℃提高到 5 2 0℃ ;在含镍非晶态合金中加入铝 ,然后用碱将铝抽出 ,使非晶态合金比表面积由 1m2 /g增加到 10 0m2 /g以上 ;在建立 30t/a非晶态合金生产示范装置中 ,自行设计了特殊的喷嘴和选用适宜的坩埚材质 ,使生产成品率由 2 0 %左右提高到 93%以上 ,利用副产的偏铝酸钠 ,合成NaY分子筛 ,形成了整体的清洁生产过程 ;重点介绍了非晶态合金加氢催化剂经在三个工厂工业应用成功 ,三项工业应用成果每年为企业创造直接效益 6 70 0万元。还报道了对磁稳定床反应器的研究开发 ,经在2 0kt/a磁稳定床加氢示范装置上 35 0 0h试验 ,其生产效率比釜式加氢过程提高 4倍 ,催化剂消耗减少 5 0 %。

NiB、NiB/MgO非晶态合金催化剂的制备、表征及其加氢性能

以KBH4为还原剂、NiSO4为被还原盐、PdCl2为诱导剂,采用诱导化学沉积法制备了系列NiB非晶态合金催化剂。将微量PdCl2负载于MgO载体上,通过化学镀法制备了NiB/MgO负载型非晶态合金催化剂。用XRD,ICP,SEM,TEM技术对催化剂的物性进行了表征,并将其用于环丁烯砜加氢反应。研究了制备条件(B/Ni摩尔比、NH3/Ni摩尔比及诱导剂的用量)对非晶态合金催化剂物化性能的影响。确定了制备NiB非晶态合金催化剂的最佳条件:硼镍摩尔比为2/1及NH3/Ni摩尔比为19/1。对于NiB/MgO负载型非晶态合金催化剂,镍的实际负载量为13 55%时,NiB/MgO催化剂与NiB催化剂的环丁烯砜加氢催化活性相当。

非晶态合金催化剂制备及其应用

介绍了非晶态合金催化剂的制备方法,其中,化学沉积负载法和添加第三组分化学沉积法制得的催化剂具有优良的催化活性和抗毒化能力,以及很高的热稳定性,因此这两种方法近年来备受关注。简述了非晶态合金催化剂在CO、CO2、烯烃、炔烃、苯、含氧或含氮化合物等的加氢反应以及析氢电催化反应中的应用;分析了现阶段非晶态合金催化剂制备和应用存在的问题,并展望了其前景。

粉末化学镀法制备NiB/NaBETA催化剂及其加氢催化性能

采用银诱导化学镀溶液自发分解法制备了纯态NiB非晶态合金催化剂 ;用粉末化学镀法分别在浸渍过微量AgNO3 的 β分子筛和没浸渍AgNO3 的 β分子筛上制备了负载型非晶态合金催化剂NiB/A BETA和NiB/N BETA。用ICP、XRD、TEM等测试技术对催化剂物性进行了表征 ,并将其用于环丁烯砜加氢反应中。结果表明 ,负载后NiB粒径明显减小。在NiB/A BETA催化剂中 ,NiB为辐射状近半圆形颗粒 ,粒径在 10 0～12 0nm之间。与NiB/N BETA相比 ,NiB/A BETA催化剂 ,由于AgNO3 的催化和定向作用 ,使NiB颗粒更加规则和分散 ,在环丁烯砜加氢反应中表现出良好活性。

非负载镍催化剂的2-乙基蒽醌加氢活性及其氢吸脱附性质

分别制备了金属镍粉、兰尼镍、Ni B非晶态合金及镧掺杂的Ni B非晶态合金 (Ni B La)催化剂 ,研究了催化剂的氢吸附和脱附性质以及对 2 乙基蒽醌加氢反应的催化性能 .结果表明 ,金属镍粉、兰尼镍和Ni B催化剂表面均具有两种氢吸附位 :弱吸附位和强吸附位 .Ni B La催化剂表面只有氢的强吸附位 ,其强吸附氢量与兰尼镍相当 .推测只有氢的强吸附位是 2 乙基蒽醌加氢反应的活性中心 ,并且Ni B La催化剂上的强吸附氢较兰尼镍上的更活泼 ,因而Ni B La非晶态合金催化剂对加氢反应的催化活性高于兰尼镍 .

温和条件下非晶态NiAl合金催化苯甲腈加氢制苄胺

由铜鼓快速淬冷法制备的非晶态NiAl合金催化剂经活化后用于催化苯甲腈加氢制苄胺的反应,考察了溶剂种类、苯甲腈初始浓度、催化剂用量、反应温度及反应压力等因素的影响,并测定了该催化加氢反应的表观活化能。实验结果表明,在催化剂用量为苯甲腈质量的6%、乙醇为溶剂、NaOH添加量为苯甲腈质量的10%、苯甲腈初始浓度2.0mol/L、反应压力2.0MPa、反应温度40℃的温和条件下反应60min,苯甲腈的转化率达到99.9%,苄胺的选择性达到95.2%。在上述条件下,苯甲腈催化加氢反应的表观活化能为20.4kJ/mol。

发泡非晶态合金对苯加氢的催化性能

采用新型发泡非晶态Ni-P合金催化剂 ,在微型固定床连续反应器上进行了苯加氢制备环己烷的实验研究。结果表明 :这种新型发泡非晶态合金催化剂具有较好的加氢催化活性和很好的选择性 ,在体系氢压为 2 .0MPa、反应温度为 3 0 0℃ ,苯的进料速率为 3mL/h的条件下 ,环己烷的单程收率为3 3 .2 8%。试验考察了该催化剂的稳定性 ,结果表明 ,在 3 60h内 ,其催化活性没有显著变化。另外 ,该催化剂具有很好的通透性 ,催化剂层前、后几乎无压差。试验还发现 ,该催化剂没有明显的诱导期 ,无需经过预处理就有很好的加氢催化活性。因此 ,发泡非晶态Ni-P催化剂有希望成为工业催化剂。

超声波辅助化学镀制备Ni-B/MgO催化剂及其催化加氢性能

在超声波条件下,利用金属诱导化学镀法制备了系列非晶态Ni-B合金和负载型Ni-B/MgO催化剂,并采用电感耦合等离子体发射光谱、X射线衍射、透射电镜、选区电子衍射和扫描电镜等手段进行了表征,考察了超声波对MgO上Ni-B形貌、组成和分散度的影响;以环丁烯砜加氢制环丁砜为探针反应,考察了Ni-B/MgO的催化性能.结果表明,Ni-B的非晶态结构不受超声波影响.制备过程中,超声波的引入能够提高活性组分的分散性,改善活性组分的粒径,催化剂的催化加氢性能得到明显改善.超声波辅助金属诱导化学镀Ni-B/MgO催化剂的最佳输出功率为80 W,制备温度为50℃.

环丁烯砜加氢新型催化剂的研究 Ι.金属诱导化学镀法制备NiB非晶态合金催化剂

采用金属诱导化学镀法制备了纯态NiB非晶态合金催化剂和NiB(Ag)/MgO,NiB/MgO负载型非晶态合金催化剂.用x射线衍射、电感耦合等离子体发射光谱和透射电镜等方法对催化剂进行了表征,并将其应用于环丁烯砜加氢反应中.实验结果表明,负载后NiB粒径明显减小.在NiB(Ag)/MgO催化剂中,NiB为辐射状球形或半球形颗粒,粒径在30～50 nm之间.由于Ag的催化、定向作用,使MB(Ag)/MgO催化剂中的NiB集簇粒子高度分散.与Raney Ni,NiB,NiB/MgO催化剂相比,NiB(Ag)/MgO催化剂表现出更好的催化活性,在环丁烯砜加氢反应中,环丁烯砜的转化率可达99.7%.