茂金属催化剂负载对丙烯间规聚合的影响

茂金属催化剂具有活性高、定向性好的特点 .采用茂金属催化剂 ,Ｅｗｅｎ[1] 首次在常温、常压下实现了丙烯的间规聚合 ,得到了高间规度 (ｒｒｒｒ >80 % )的间规聚丙烯 (ｓＰＰ) .ｓＰＰ因其透明性好、耐冲击及耐辐射 ,室温韧性、热密封性及透气性好等特性 ,作为共混材料 ,在医疗产品、包装、纤维、薄膜和汽车配件等方面显示了广阔的应用前景 .国内外许多公司都投入大量人力、物力进行研究 .其中 ,Ｆｉｎａ公司处于技术领先地位 .Ｆｉｎａ公司继 1 987年开发出间规选择性茂金属催化剂后 ,成功地进行了中试聚合实验 ,得到了商用ｓＰＰ .1 994…     

M-Na-P-Mo-V/SiO2系列催化剂对异丁烯氧化反应的催化性能

 以浸渍法制备了M－Na－P－Mo－V／SiO2系列催化剂,并用FT－IR和TPR对催化剂进行了表征,考察了催化剂上的异丁烯化反应．结果表明,在空速900h－1和345℃的反应条件下,过渡金属的引入可提高甲基丙烯醛的选择性．其中Cu对催化性能的改善最佳,甲基丙烯醛选择性可达65．7％;而在Na－P－Mo－V／SiO2催化剂上,乙酸选择性可达50％,但甲基丙烯醛选性仅为4．1％．在催化剂中引入过渡金属时,Cu在提高甲基丙烯醛选择性的同时,也抑制了完全氧化产物COx的生成;Fe提高双键断裂产物和完全氧化产物选择性的同时,使甲基丙烯醛选择性下降;Zn对反应的影响不很大．TPR结果表明,在入Cu的催化剂中,Cu与杂多酸阴离子之间可能存在“溢流”作用．     

聚γ-(β-氰乙基)胺丙基硅氧烷铂配合物的合成与催化性能

γ-氨丙基三乙氧基硅烷与丙烯腈反应，得到γ-(β-氰乙基)胺丙基三乙氧基硅烷。后者用气相法二氧化硅固载，再与氯亚铂酸钾反应，合成了聚γ-(β-氰乙基)胺丙基硅氧烷铂配合物。研究了它对不饱和烃与三乙氧基硅烷的硅氢加成反应的催化特性。     

Effect of Transition Metals (Cu, Co and Fe) on the Autothermal Reforming of Methane over Ni/Ce0.2Zr0.1Al0.7Oδ Catalyst

The transition metals (Cu, Co, and Fe) were applied to modify Ni/Ce0.2Zr0.1 Al0.7Oδcatalyst. The effects of transition metals on the catalytic properties of Ni/Ce0.2Zr0.1 Al0.7Oδautothermal reforming of methane were investigated. The Ni-supported catalysts were characterized by XRD, TPR and XPS. Tests in autothermal reforming of methane to hydrogen showed that the addition of transition metals (Cu and Co) significantly increased the activity of catalyst under the conditions of lower reaction temperature, and Ni/Cu0.05Ce0.2Zr0.1Al0.65Oδwas found to have the highest conversion of CH4 among all catalysts in the operation temperatures ranging from 923 K to 1023 K. TPR, XRD and XPS measurements indicated that the cubic phases of CexZr1-xO2 solid solution were formed in the preparation process of catalysts. Strong interaction was found to exist between NiO and CexZr1-xO2 solid solution. The addition of Cu improved the dispersion of NiO, inhibited the formation of NiAl2O4, and thus significantly promoted the activity of the catalyst Ni/Cu0.05Ce0.2Zr0.1Al0.65Oδ.     

Influence of Pretreatment on the Interaction of Oxygen with Silver and the Catalytic Activity of Ag／SiO2 Catalysts for CO Selective Oxidation in H2

The interactions of oxygen with pre~reduced silver catalysts as well as their catalytic propertiesfor CO selective oxidation in H2 after oxygen pre-treatment are studied in this paper. It is found that the pretreatment exerts a strong influence on the activity and selectivity of the silver catalyst. A drop in activity and selectivity is observed after treating a pre-reduced catalyst with oxygen at low temperatures,whereas a converse result is obtained after an oxidizing treatment at high temperatures (T≥350℃). O2-TPD results show that surface oxygen species adsorbs on silver surface after the oxygen treatment at low temperatures. However, penetration of oxygen into the silver is enhanced by a high temperature treatment, meanwhile the surface oxygen species disappear. No other silver species except metallic silver are observed on all the catalysts by XRD, and the size of silver particle is not changed after the treatment with oxygen at low temperatures. The surface oxygen species formed by oxygen treatment can also be removed by hydrogen reduction. The strongly-adsorbed surface oxygen species prohibit the adsorption and diffusion of oxygen species in reaction gas on the surface of silver catalyst, causing the decrease in CO oxidation activity, in other words, it is important to obtain a clean silver surface for increasing the catalyst activity in CO removal from H2-rich feed gas. The differences in activity and selectivity due to the oxygen pretreatment at different temperatures axe discussed in terms of the changes in the surface/subsurface oxygen species of the silver particles.     

Ni/Al2O3-SiO2催化剂对轻质C5馏分加氢的催化性

 利用X射线衍射、热重-差热分析和孔结构分析对新鲜和失活的Ni/Al2O3-SiO2催化剂进行了表征,讨论了催化剂的失活机理,并考察了催化剂在轻质C5馏分加氢反应中的稳定性和加氢工艺条件. 结果表明,催化剂失活的主要原因是加氢原料中的硫化物与催化剂活性组分镍发生反应生成了Ni3S2、镍晶粒长大和催化剂结焦. 使用氧化锌脱硫剂将加氢原料脱硫后,在单个反应器内,用饱和烷烃稀释C5馏分至其中二烯烃的质量分数为6%～9%,在加氢压力为1.3～2.5 MPa,体积空速为5.0～6.0 h-1,H2/油体积比为80～120的条件下,原料中二烯烃和炔烃转化率为100%,单烯烃转化率在97%以上. 催化剂连续运行375 h后,其催化活性与新鲜催化剂基本相同.     

磷改性β沸石催化剂上催化裂化轻汽油的醚化

在小型固定床反应装置上,考察了负载磷的β沸石催化剂的制备条件对其催化性能的影响以及醚化反应温度、压力、醇烯摩尔比、LHSV对醚化反应的影响。实验结果表明,浸渍磷的质量分数为2%的Hβ催化剂具有较好的醚化活性。在最佳反应条件(温度70 ℃,压力0.8 MPa,LHSV 1.0 h-1,醇烯摩尔比1.0)下,该催化剂的叔碳烯烃的总转化率可达到56.91%。负载磷后的催化剂具有活性好、选择性高、不易失活等优点。反应性能均优于Hβ催化剂。     

三价轻希土—PMBP—路易斯碱三元配合物的合成及其性质的研究

合成了1—苯基—3—甲基—4—苯甲酰基—吡唑啉酮—5(PMBP)和路易斯碱的三价轻希土三元配合物LnA_3·L(A=Pmbp~-;L=C_2H_5OH时,Ln=La、Pr、Sm、对Gd为GdA_3·(C_2H_5OH)_(0·25);L=Phen(邻菲罗啉)时,Ln=Pr-Gd,L=TBPO(三丁基氧化膦)时,Ln=La、Pr—Gd)。测定了它们的摩尔电导值、热谱、红外光谱、可见—紫外光谱、荧光光谱和质子核磁共振谱。观察到热稳定性次序为LnA_3·Phen>LnA_3·TBPO。从同类型配合物系列的热效应值、LnA_3·Phen型配合物的合成难易程度及其紫外最大吸收波长的移动可观察到镧系收缩现象。     

负载离子液体纳米钯催化芳卤羰化反应

研究了高分散性的负载离子液体纳米钯催化剂的制备及其催化芳卤羰化反应的性能. 用XRD、HRTEM和XPS等方法对催化剂进行了表征, 结果表明, 钯组分处于高分散零价态, 其平均粒径小于5 nm, 且催化剂表面存在一厚度适中的离子液体液膜, 有利于提高催化剂的稳定性; 该催化剂对PhI、PhBr、PhCl的羰化反应的催化活性优于离子液体两相催化体系, 在优化的反应条件下, 碘苯的转化率可达99.3％, 生成苯甲酸乙酯的转化频率(TOF)可高达4926 h−1, 反应产物中苯甲酸乙酯的选择性大于99％.     

微波促进活性炭负载磷钨酸催化合成短链季戊四醇双缩醛

以活性炭负载磷钨酸为催化剂,用微波辐射法合成了5种短链季戊四醇双缩醛(3a~3 e),其中季戊四醇双缩丙醛(3b)未见文献报道。3的结构经1H NMR,IR和元素分析表征。