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1.
非晶态CoNiB能催化糠醛液相加氢制糠醇   总被引:1,自引:0,他引:1  
采用化学还原法制备了CoNiB非晶态合金催化剂,并用于糠醛液相加氢制糠醇反应。考察了Ni/Co摩尔比,NaBH4滴加速率等催化剂制备条件对催化性能的影响,以及反应压力、反应时间、反应温度等反应条件对糠醛转化率和糠醇选择性的影响。结果表明:最佳的催化剂制备条件是Ni/Co摩尔比为5/5,NaBH;滴加速率为2.6mL·min2;最佳的反应条件为反应压力2MPa,反应时间3h,反应温度80℃。在此条件下糠醛的转化率为46.2%,糠醇的选择性为90.4%。  相似文献   

2.
糠醛气相加氢制糠醇催化剂的研制   总被引:6,自引:1,他引:6  
用溶胶凝胶法制得糠醛加氢制糠醇的Cu-Zn-Al-A催化剂,研究了制备条件对催化剂性能的影响,并对催化剂进行了TPR、BET、XRD等表征。该催化剂活性评价结果表明,在常压、反应温度130℃、糠醛进料量为2ml/h和氢醛摩尔比为9∶1的条件下,糠醛转化率为99.8%,糠醇选择性为97.77%。  相似文献   

3.
糠醛在Pd-Cu膜反应器中催化加氢合成糠醇   总被引:2,自引:0,他引:2  
以糠醛催化加氢合成糠醇作为模型反应,采用共沉淀法制备的Cu/MgO-K2O作为催化剂,考察了Pd-Cu膜反应器的加氢性能.膜反应器由双套管组成,采用分别进料的方式操作.即糠醛气化后由载气带入中心膜管的催化床层,而氢气则进入管壳层通过Pd-Cu合金膜渗透到反应区.在不同条件下分别进行糠醛催化加氢反应,考察了糠醛转化率、产品糠醇选择性和收率,并与传统的共进料填充床反应器进行比较.研究结果显示,膜反应器比传统的填充床反应器具有产品收率高、选择性好和副产物少的特点.此外,本文结合催化剂的组成、结构和表面形貌的表征对催化剂的催化活性和失活行为进行了讨论.  相似文献   

4.
5.
Tetrahydrofurfuryl alcohol could be obtained by catalytic hydrogenation of either furfural or furfuryl alcohol using Pd-, Ru-, Rh- and Ni-supported catalysts as well as their mixtures with a Cu-supported catalyst. In the case of furfural hydrogenation, the best results (97 % yield, 100 % conversion, 98 % selectivity) were obtained in the presence of Ni and Cu. However, this catalytic mixture could not be recycled. In the case of furfuryl alcohol hydrogenation, Ni-supported catalysts were the most active. Nickel-onsilica-alumina catalyst containing 59 % of metal lead to the best results (98–99 % yield, selectivity and conversion >99 %). Moreover, it could be recycled. Hydrogenation of furfuryl alcohol in the presence of this catalyst was the best procedure for the production of tetrahydrofurfuryl alcohol.  相似文献   

6.
雷经新  石秋杰 《化学试剂》2006,28(4):205-208,251
综述了近10年来催化剂在糠醛加氢制糠醇反应中应用的研究成果及催化剂的研究热点,展望了催化剂的发展方向。  相似文献   

7.
Vapour phase oxidation of furfural over vanadium pentoxide catalyst was studied using an isothermal flow reactor in the temperature range of 220–280°C. Maleic anhydride and carbon dioxide are found to be formed from furfural by a parallel reaction scheme. The following rate equation based on the two-stage redox mechanism—the substance to be oxidized reduces the catalyst which in turn is reoxidized by oxygen from the feed—is found to explain the data satisfactorily.
The reoxidation of the reduced catalyst was found to be the rate controlling step.  相似文献   

8.
9.
采用浸渍法制备Co改性γ-Al2O3负载的Cu-Zn催化剂,考察Cu-Zn负载量、Co含量及反应温度等对催化剂性能的影响。结果表明,在413 K、氢气流速0.5 mL·s-1 和糠醛空速2 h-1 条件下,当催化剂Cu-Zn/γ-Al2O3(Co)中n(Cu)∶n(Zn)∶n(Al)∶n(Co)=1.0∶2.0∶3.0∶0.51时,糠醇的选择性100%,糠醛转化率94.6%,比使用单纯Cu-Zn/γ-Al2O3催化剂的最佳转化率提高11%。  相似文献   

10.
闫艳娇  陈晓春  肖楠 《现代化工》2004,24(Z1):181-183
开发了一种镍基催化剂,该催化剂用于糠醇加氢制备四氢糠醇时表现出良好的性能.实验考察了催化剂中载体含量和第二金属铜含量对催化剂性能的影响规律,结果显示当载体含量为40%~30%,镍铜原子比为61~31时,催化剂性能最优,糠醇转化率高于99.5%,四氢糠醇收率和选择性均高于98%.  相似文献   

11.
制备了一种新型、无毒Cu-Zn-Ca/γ- Al2O3配合物催化剂。采用固定床反应器,进行糠醛常压气相催化加氢反应,考察反应温度、催化剂组成、空速和氢醛比等因素的影响。结果表明,在508 K、空速0.32 h-1、还原温度保持(493~513) K、活化6 h和氢醛物质的量比为10∶1条件下,糠醛转化率达到98.90%,2-甲基呋喃选择性达92.30%,2-甲基呋喃收率达91.28%。作为一种新型的无Cr催化剂,无毒,无污染,可代替Cu-Cr催化剂用于糠醛加氢过程,高活性和高选择性地制取2-甲基呋喃。  相似文献   

12.
采用溶胶-凝胶法制备了Cu/Ni超细混合催化剂,并用于糠醛液相加氢制2-甲基四氢呋喃反应。考察了Cu/Ni摩尔比,Na2CO3溶液浓度等催化剂制备条件,以及合成反应中反应压力、反应时间、反应温度等反应条件对糠醛转化率和2-甲基四氢呋喃选择性的影响。结果表明:催化剂制备条件为Cu/Ni摩尔比为5/5,Na2CO3溶液浓度为1.0 mol/l;合成反应条件为反应压力8 MPa,反应时间3.5 h,反应温度180 ℃;产品经气相色谱检测分析,糠醛的转化率为100%,2-甲基四氢呋喃的选择性为64.52%。  相似文献   

13.
采用化学共沉淀方法制备了铜氧化物催化剂FAH-1。在30 mL绝热微型固定床反应器上,研究了催化剂催化糠醇加氢制备1,2-戊二醇的性能,并对相关工艺条件进行了考察。实验结果表明:FAH-1催化剂表现出良好的糠醇加氢活性和选择性,在反应温度为160 ℃、反应压力为6 MPa、液时体积空速为0.3 h -1、氢油体积比为10 000∶1条件下,糠醇加氢反应的转化率和选择性分别为91.80%和41.52%,1,2-戊二醇单程收率达到38.12%,1 000 h长周期评价催化剂性能稳定。制得的1,2-戊二醇样品纯度高、质量好,满足后续加工对1,2-戊二醇的质量要求。反应过程采用固定床反应器,具有较好的工业化前景。  相似文献   

14.
The effect of water on Cu/Zn catalyst prepared by co-precipitation for hydrogenation of methyl laurate in a slurry phase was studied using a stirred autoclave reactor system. The catalysts were characterized by means of XRD, BET, H2-TPR, SEM and TEM. The results indicate that catalytic activity decreases with increased amount of water in methyl laurate. Correlating with the results from the above characterization, it is found that the main causes for the water deactivation of the Cu/Zn catalyst were the water occlusion of active catalyst sites by the low solubility of water in the substrate and the promotion of crystal growth, as well as the Cu/Zn catalyst agglomeration in the presence of water.  相似文献   

15.
NiB/SiO2 amorphous alloy catalyst was prepared by power electroless plating method and characterized by induction coupled plasma (ICP), Brunauer-Emmett-Teller method (BET), transmission electron microscope (TEM) and X-ray diffraction (XRD) techniques. The catalytic performance of NiB/SiO2 was investigated for the hydrogenation of furfuryl alcohol (FA) to tetrahydrofurfuryl alcohol (THFA). The effects of operational conditions, such as reaction temperature, pressure, and stirring rate were carefully studied. The proper conditions were determined as the following: pressure 2.0 MPa, temperature 120°C and stirring rate 550 r/min. A typical result with FA conversion of 99% and THFA selectivity of 100% was obtained under such conditions, which was close to that over Raney Ni. Translated from Journal of Fuel Chemistry and Technology, 2006, 34(4), 483–486 [译自: 燃料化学学报]  相似文献   

16.
A facile synthesis of the hierarchical Ni/MgO catalyst is reported, with extremely fine dispersion of Ni nanoparticles (NPs) and high surface oxygen mobility. The hierarchical Ni/MgO catalyst exhibits higher activity for CH4 formation than that prepared by the impregnation method. The enhanced activity and thermal stability of the hierarchical Ni/MgO catalyst is attributed to hierarchical MgO particles with a multilayer structure and high surface oxygen mobility. This induces better metal‐support interactions, high Ni dispersion to prevent Ni NPs sintering, and the high surface oxygen mobility provides a high resistance to carbon deposition. Compared to the impregnated Ni/MgO catalyst, the hierarchical Ni/MgO catalyst exhibits a better fluidization quality and a higher attrition‐resistance in a fluidized‐bed reactor. This approach to improve the catalytic activity by creation of hierarchical Ni/MgO particles is encouraging for the design of novel catalysts for synthetic natural gas production, especially from the perspective of matching catalysts with fluidized‐bed reactors. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2141–2152, 2017  相似文献   

17.
糠醇生产中废弃物的循环回用新工艺   总被引:4,自引:1,他引:3  
将糠醛液相加氢生产糠醇产生的废渣置于真空干燥箱中 ,在较低的负压状态下保持 1 30℃的温度 ,蒸馏回收废渣中的有机物 ,返回糠醇精制车间获得合格的糠醇与糠醛产品 ;剩余的固体废弃物与纯碱混合 ,在反射炉中焙烧 ,浸取获得铬酸钠水溶液 ;最后剩下的粗氧化铜溶于硝酸得到硝酸铜溶液 ;将铬酸钠溶液、硝酸铜溶液按一定比例混合 ,加入氨水搅拌 ,分离出的沉淀经传统方法焙烧活化、造粒制得新催化剂 ,回用于糠醛液相加氢生产糠醇。铬组分和铜组分的回收率均在 90 %以上  相似文献   

18.
In the present work, a series of Pt-based catalysts, alloyed with a second metal, i.e., Re, Sn, Er, La, and Y, and supported on activated carbon, ordered mesoporous carbon, N-doped mesoporous carbon or reduced graphene oxide(rGO), have been developed for selective hydrogenation of cinnamaldehyde to cinnamylalcohol. Re and rGO were proved to be the most favorable metal dopant and catalyst support, respectively. Pt_(50) Re_(50)/rGO showed the highest cinnamylalcohol selectivity of 89% with 94% conversion of cinnamaldehyde at the reaction conditions of 120 °C, 2.0 MPaH_2 and 4 h.  相似文献   

19.
《Catalysis communications》2011,13(15):1428-1431
Metallic ruthenium nanoparticles intercalated in hectorite (particle size ~ 4 nm) were found to catalyse the hydrogenation of furfuryl acohol to give tetrahydrofurfuryl alcohol in methanolic solution under mild conditions. The best results were obtained at 40 °C under a hydrogen pressure of 20 bar (conversion 100%, selectivity > 99%). After a total turnover number of 1423, the hectorite supported ruthenium nanoparticles are deactivated but can be recycled and regenerated.  相似文献   

20.
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