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1.
铁酸盐的制备、表征及其催化性能的研究   总被引:11,自引:0,他引:11  
采用空气氧化湿法制备了含Zn、 Ni、 Co的尖晶石型铁酸盐。运用XRD、IR、UV-DRS和TPR等方法对所制备的样品进行了表征。研究了铁酸盐的化学组成、结构和氧化还原性质。考察了铁酸盐对二氧化碳选择性氧化乙苯制苯乙烯的催化性能,并讨论了催化剂的结构、组成对反应活性的影响以及二氧化碳的作用。  相似文献   

2.
负载型Ni-B非晶态合金催化剂的表征及催化性能   总被引:22,自引:0,他引:22  
马爱增 《催化学报》1999,20(6):603-607
采用ICP,XRD,DSC,BET,SEM和TEM等技术对负载型Ni-B非晶态合金催化剂进行了表征,研究了这类催化剂对乙烯中微量乙炔的选择加氢性能.结果表明,在负载型非晶态合金催化剂中,Ni-B以超细微粒的形式分散在载体上,但在不同载体上的分散度不同.通过载体的引入,提高了非晶态合金的热稳定性,阻止了超细Ni-B的聚集.负载型非晶态合金催化剂对乙烯中微量乙炔的选择加氢表现出优良的催化性能.  相似文献   

3.
The effects of surface acidity-basicity and surface oxidation reduction property of Li-La-Mn/TiO2 (I) and Li-La-Mn-W/TiO2 (II) catalysts on oxidative coupling of methane were studied by CO2-temperature programmed desorption (CO2-TPD) and temperature programmed reduction temperature programmed oxidation (TPR-TPO). The results show that there exist strong basic sites on catalysts I and II, but the quantity of these sites on catalyst II is more than that on catalyst I. Besides, the strength of basics site on catalyst II is stronger than that on catalyst I. The surface of catalyst II is easier to reduce and re-oxidize than that of catalyst I. The surface of catalyst II is easier to reduce and re-oxidize than of catalyst I, and the extent of reduction and reoxidation of catalyst II is more intensive than catalyst I, which results in a lowing of the reaction temperature and enhances the activity and C2 hydrocarbon yield as well as gas hourly space velocity(GHSV). Catalyst II is excellent for the oxidative coupling of methane (OCM).  相似文献   

4.
Pt-Sn/MgAl2O4催化剂的TPR和H2-TPD研究   总被引:3,自引:0,他引:3  
Pt Sn/MgAl 2O 4 catalysts prepared by co impregnation with nominal 0 35% platinum and varying content of tin (0~2 5%) were characterized by temperature programmed reduction (TPR) and temperature programmed desorption of hydrogen (H 2 TPD). TPR results showed that platinum catalyzed the reduction of tin. However, the average oxidation state of tin after reduction depended upon the concentration of tin on the catalysts. H 2 TPD data indicated that tin addition inhibited the inactivated adsorption of hydrogen but promoted the activated adsorption, implying that tin modified both the ensembles of platinum and metal support interface, thus increasing hydrogen mobility and promoting hydrogen spillover.  相似文献   

5.
负载型铜基超细催化剂的制备、表征和催化性能   总被引:5,自引:0,他引:5  
超细粒子作为一种新型催化材料以其高活性和优良的选择性引起催化工作者的重视.超细粒子的制备方法有很多种,其中溶胶凝胶法是金属氧化物超细粒子制备的重要方法之一[1].目前,关于负载型超细粒子的制备方法主要是溶胶凝胶超临界干燥,一类是由超细载体浸渍以活性组...  相似文献   

6.
A silica-supported carboxymethylcellulose platinum complex (abbreviated as SiO_2-CMC-Pt) has been prepared and characterized by XPS. Its catalytic properties for hydro-genation of aromatic compounds were studied. The results showed that this catalystcould catalyze the hydrogenation of phenol, anisol, p-cresol, benzene and toluene to cyclo-hexanol, cyclohexyl methyl ether, p-methyl cyclohexanol, cyclohexane and methylcyclo-hexane, respectively in 100% yield at 30℃ and 1 atm. In the hydrogenation of phenol,COO/Pt ratio in SiO_2-CMC-Pt has much influence on the initial hydrogenation rate andthe selectivity for the intermediate product, cyclohexanone. The highest initial rate andthe highest yield of cyclohexanone both occur at COO/Pt ratio of 6. The complex is stableduring the reaction and can be used repeatedly.  相似文献   

7.
8.
1yttroductionIMcthancactivationisoncofthemostintriguingsubjectsinheterogencouscatal}'sisbccauscmcthancisathcrmod}namicall}'stabIccompoundt`ithanoblcgas-likeconfiguration.0fintcrcstsisthcrcccntt"orkreportcdb}'KocrtsIll,BeIguedl21.andYanl3ltthosucccssfull}'convcrtnaturalgasintohighcrh}.drocarbonsb}'thctt"o-stcproutcinwhichnaturalgasisfirstthcrmall}'activatcdonthctransitionmctalcatal}.stsatmoderatctemperature.Toasccrtainthcnaturcofrcactionsofmcthane.thcactivationofmcthaneisextensivel)'invcstiga…  相似文献   

9.
富勒烯及其衍生物的催化性能的研究是当前的一个热点,并显示出良好的工业应用前景[1].研究表明,富勒烯及其衍生物的金属配合物对氢化[2,3],不对称偶联[4],烯烃的聚合[5]等都有优异的催化性能.我们也发现C60Pt(PPh3)2和C60Ptn是高效...  相似文献   

10.
有机硅聚合物负载环硫乙烷铂配合物的合成与催化性能   总被引:6,自引:1,他引:6  
<正> 有机硅聚合物负载硫醚与铂的配合物可作为烯烃硅氢加成的有效催化剂,但其中部分配合物的回收再用性能不太理想,合成亦比较繁琐。考虑到环硫乙烷中硫原子的未共用电子对远比一般硫醚中硫原子的未共用电子对更加暴露,有可能与过渡金属形成更稳定的配合物,从而减少催化过程中金属的流失,我们合成了气相法二氧化硅固载的聚-4-氧杂-6,7-环硫庚基硅氧烷铂配合物,研究了该配合物对烯烃硅氢加成反应的催化性能。本文报道所得到的一些结果。  相似文献   

11.
Styrene-acrylic acid copolymer (SAAC)-supported iron complex (SAAC·Fe)was characterized and the effect of the characteristic parameters on the catalytic activity of the complex was investigated. IR spectrum suggested that the complex SAAC·Fe possesses a structure of(C)and the Fe-O bond is higher in covalency.The complex SAAC·Fe with the structure of(C)shoved a higher catalytic activity in butadiene polymerization. When Fe/-COOH molar ratio in SAAC·Fe was about 0.2 the complex gave optimum catalytic activity. The catalytic activity of SAAC·Fe with the higher content of long sequence of acrylic acid units was low. When the content of the short sequence of acrylic acid units was predominant and at the same time the content of the short sequence was approximately equal to that of the long sequence for stryrene, the activity of the complex was high.  相似文献   

12.
壳聚糖钯配位络合物的合成、表征及其催化性能研究   总被引:1,自引:0,他引:1  
用不同方法制备了壳聚糖钯配住络合物,并用FFIR,XPS,XRD和DTA-TG对其进行了表征,结果表明壳聚糖与钯发生配住作用形成了壳聚糖钯配位络合物,研究了该络合物对碘代笨与丙烯酸进行交叉偶联烷基化反应的催化性能,结果表明其具有良好的催化活性。  相似文献   

13.
在220℃和50-60大气压条件下,利用固定床对NiO/SiO2、NiO/Al2O3、NiO-La2O3/Al2O3和NiO-Bi2O3/Al2O3催化剂上的乙炔与甲酸甲酯加氢酯化合成丙烯酸甲酯进行了研究。镍基催化剂对乙炔的加氢酯化合成丙烯酸甲酯具有很好的活性。用浸透法制备的Mo/SiO2催化剂的活性和丙烯酸甲酯的选择性均比离子交换法差。NiO/Al2O3催化剂用La或Bi改性后,其催化活性大大提高。XPS、XRD和TPR结果表明,当催化剂用La或Bi改性后,NiO的晶粒明显减小,催化剂表面的Ni/Al原子比增大,催化剂的第二个还原峰温大大降低。  相似文献   

14.
研究了酸处理对sepiolite结构的影响及环己烷在Pt/sep-Al2O3催化剂上的脱氢性能。结果表明,酸处理能使Sepiolite骨架中的呐“发生解离,生成一种高比表面积的产物。环己烷在经酸处理的sepiolite担载Pt催化剂上的脱氢活性远较Pd/Al2O3高。研究结果还表明,在Pt/sep-Al2O3催化剂上,电子效应较几何效应对环己烷脱氢作用更显著。  相似文献   

15.
总结了复载不同纳米尺度的复合载体及其CoMo催化剂的表面酸性及孔结构特性的表征结果。结果表明,负载型纳米TiO2与基载体γ-Al2O3存在着相互作用。当负载比较少量的纳米TiO2时,复合载体的总酸量随着TiO2含量的增加而增加,超过γ-Al2O3的酸量,但当 TiO2的含量比较高时复合载体的酸量又降低,纳米TiO2优先负载在γ-Al2O3的强酸中心位;负载了CoMo活性组分后酸量增加。不同粒径的纳米TiO2对复合载体和催化剂的酸分布没有明显影响,但对总酸量有影响。对不同尺度TiO2,随着TiO2负载量的增加以及负载金属活性组分的增加,表面积、孔容和最可几孔径均有不同程度的减少。  相似文献   

16.
丁二醇二丙烯酸酯、丙烯酸甲酯、丙烯酸β-氯乙酯或丙烯酸ω-氯己酯进行三元共聚,合成了两类4种带ω-氯侧基的交联型聚丙烯酸酯.它们以乙硫醇硫醚化,再与氯亚铂酸钾反应,得到4种交联型聚丙烯酸酯负载的硫铂络合物.这些络合物对癸烯-1、十二烯-1、苯基烯丙醚、苯乙烯与三乙氧基硅烷的硅氢加成反应具有良好的催化活性.讨论了温度、催化剂用量对催化性能的影响及催化剂的重复使用情况.  相似文献   

17.
固体超强酸SO2-4-MoO3-TiO2的制备及其催化酯化性能研究   总被引:4,自引:0,他引:4  
In this paper a new solid superacid catalyst SO2-4-MoO3-TiO2 was prepared.The activity of the catalyst in esterification of acetic acid and iso-amyl alcohol was measured and compared with that of SO2-4-TiO2 and MoO3-TiO2.The results showed that SO2-4-MoO3-TiO2 had better catalytic performance than SO2-4-TiO2 and MoO3-TiO2.There was evident coordination between MoO3 and SO2-4 when they coexisted on TiO2.  相似文献   

18.
N,N-双(β-甲硫乙基)γ-(三乙氧硅基)丙胺用气相法二氧化硅固载,再与氯亚铂酸钾作用,合成了三齿型铂配合物-聚γ-[N,N-双(β-甲硫乙基)胺基]丙基倍半硅氧烷铂配合物.研究了该配合物对烯烃与三乙氧基硅烷的硅氢加成反应的催化特性.  相似文献   

19.
SnFe2O4 nanocrystals (NC), prepared with a simple one‐step carrier‐solvent‐assisted interfacial reaction process, were developed as highly efficient catalysts for hydrogen peroxide sensing. These NCs, with a size of around 7 nm, served as the sensing catalyst and were decorated onto the pore surfaces of a porous fluorine‐doped tin oxide (PFTO) host electrode, prepared from commercial FTO glass with a simple anodic treatment, to form the sensing electrode for hydrogen peroxide. The SnFe2O4 NCs‐loaded PFTO electrode exhibited an ultra‐high sensitivity of 1027 mA m ?1 cm?2 toward hydrogen peroxide, outperforming Pt NCs‐loaded PFTO electrodes. The SnFe2O4 NCs‐loaded PFTO electrode proved a promising relatively low cost, high performance sensing electrode for hydrogen peroxide.  相似文献   

20.
聚苯乙烯负载氨基硒醚铂配合物的合成及其催化性能   总被引:8,自引:0,他引:8  
β-羟基-β’-二甲氨基二乙基硒醚与氯甲基化聚苯乙烯在二氧六环中及氢化钠存在下缩合,再在丙酮中与氯亚铂酸钾反应,得到聚苯乙烯负载二甲氨基乙基硒醚铂配合物。该配合物对烯烃与三乙氧基硅烷的硅氢化反应具有良好的催化活性。  相似文献   

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