共查询到20条相似文献,搜索用时 905 毫秒
1.
2.
采用共沉淀法制备了Cu-Zn-Al催化剂。对其通过XRD,H2-TPR,H2-TPD,NH3-TPD和CO2-TPD等方式进行表征,并结合醋酸甲酯加氢反应进行评价,研究了助剂对催化剂结构和性能的影响,考察了反应条件对催化剂醋酸甲酯加氢反应性能的影响。结果表明,加入助剂Ba使催化剂具有较好的酯加氢活性及稳定性。在220℃、H2压力3.0 MPa、n(H2)/n(醋酸甲酯)为30.0、空速1.5 h-1条件下,Cu-Zn-Al-B催化剂上醋酸甲酯转化率接近96.0%,乙醇选择性约为97.0%。 相似文献
3.
4.
5.
6.
加氢催化剂预硫化技术探讨 总被引:11,自引:1,他引:10
1前言加氢催化剂大多采用Mo、Co、Ni、W等金属元素作组分,并以氧化态分散在多孔的载体上。大量的研究试验结果表明,这种形态的催化剂加氢活性低,活性稳定性差。若将催化剂经过预硫化处理,即在硫化剂和氢气存在下使氧化态金属转化为硫化态金属,则硫化态催化剂的活性和稳定性均高于氧化态催化剂。催化剂预硫化技术是加氢催化剂开发应用的关键步骤之一。当今,随着催化剂制备技术的发展,促进了国内外对加氢催化剂预硫化技术的基础研究和应用研究。最佳的预硫化技术能够使加氢催化剂保持最佳的加氢活性和活性稳定性,提高催化剂的选择性… 相似文献
7.
8.
9.
10.
制备了用于双环戊二烯(DCPD)固定床连续式加氢合成桥式四氢双环戊二烯的负载型Ni基催化剂。利用低温氮气吸附(BET)、X射线晶体衍射(XRD)以及程序升温还原(H2–TPR)等手段对催化剂进行表征。结果表明,Ni–Cu/γ–Al2O3催化剂具有更好的加氢活性和稳定性,Cu的加入可降低Ni O的还原温度,促进Ni O在载体表面的分散,有利于加氢活性的提高。此工作为筛选更适合DCPD固定床连续加氢催化剂提供理论和实验依据。 相似文献
11.
苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)选择性催化加氢是保留链段中苯环不被加氢而C C双键选择性加氢,从而得到具有更优异性能的高附加值氢化产物SEBS。为了消除反应物大分子孔内扩散限制问题,采用胶体SiO2亚微米球为模板,通过氰胺热缩合成功合成了三维有序超大孔氮化碳(3DOM g-C3N4),以其为载体采用化学还原负载法得到了具有超大孔结构的Pd/3DOM g-C3N4催化剂,并将其用于SBS的选择性催化加氢反应。结果表明,Pd/3DOM g-C3N4催化剂具有超大孔-大孔-介孔多级孔三维贯穿结构且Pd颗粒尺寸小、分散均匀,该催化剂在较为温和的反应条件下,即表现出极为优异的加氢活性和选择性。根据红外表征计算得到其对SBS的1,2-C C和1,4-C C总加氢度达到98%,而对苯环没有加氢,选择性为100%。其优异的催化性能主要归功于载体独特的超大孔-大孔-介孔多级孔三维贯穿结构可以有效消除大分子在孔隙中的扩散限制,从而提高了对活性位... 相似文献
12.
13.
The hydrogenation of acetophenone and its derivatives was studied using several supported Ni catalysts. Ni supported on zeolite Y catalyst offered the best hydrogenation activity. However, the activity of this catalyst decreases significantly on recycle and the extent of deactivation differs with respect to the substrate investigated. It is shown in this paper that a bimetallic Ni-Pt catalyst gives improved stability on recycle for hydrogenation of acetophenone and its derivatives. The role of zeolite Y support and a strong synergistic effect in a bimetallic Ni-Pt catalyst has been discussed. 相似文献
14.
15.
碳二加氢催化剂的工业应用 总被引:2,自引:0,他引:2
在对进口G-58 C和国产LY-C2-02催化剂在兰州石化乙烯装置碳二加氢单元二段反应器的工业应用数据进行分析和比较的基础上,考察了改进型LY-C2-02催化剂的工业应用性能。结果表明:与G-58C催化剂相比,改进型LY-C2-02催化剂具有活性和选择性比较高、操作弹性范围宽、操作稳定等特点,完全适应6000 h-1空速的工艺条件,综合性能与G-58C催化剂水平相当;LY-C2-02催化剂具备替代进口G-58C型催化剂的能力,对实现碳二加氢催化剂国产化、降低乙烯装置成本、增加效益有一定的现实意义。 相似文献
16.
以四甲基乙二胺-苯硫醚为双配体制备了新型铑钌加氢催化剂,研究了这种催化剂对NBR的加氢活性,主要考察了催化剂浓度以及反应温度、时间、氢气压力、胶液浓度对NBR溶液加氢性能的影响,得到了新型双金属双配体催化剂对NBR加氢的较佳工艺参数.同时在自行设计的动力学研究装置上,测试了催化剂对NBR加氢的空气稳定性,其空气稳定性优于现有的其他贵金属加氢催化剂.与几种商业化的胶的性能进行了对比,自制的HNBR产品力学性能达到了工业化产品的水平,表明这种新型催化剂具有高活性、好的选择性以及优良的实用性. 相似文献
17.
18.
NCG-98H新型苯加氢催化剂的工业应用 总被引:1,自引:0,他引:1
孙书田 《化学工业与工程技术》2010,31(2):47-49
介绍了NCG-98H新型苯加氢催化剂在环己烷装置中的应用情况。应用结果表明,新型苯加氢催化剂具有催化活性及选择性高、热稳定性好、副产蒸汽压力高、工业装填方便等特点,经济效益显著,值得在同类装置上推广应用。 相似文献
19.
Y. El-Shattory L. deMan J. M. deMan 《Journal of the American Oil Chemists' Society》1980,57(12):402-404
The AOCS Recommended Practice for testing activity of hydroge-nation catalysts was used to compare activity and properties
of a number of commercial catalysts with the AOCS standard catalyst. Four of five commercial catalysts tested were similar
to the standard but one commercial catalyst was markedly more active and more selective. It also was very difficult to filter
after hydrogenation. Selectivity of the catalysts in hydrogenation of soybean oil was determined from change in fatty acid
composition. The most selective catalyst produced the highest level oftrans isomers and the highest dropping point. Solid fat contents measured after 30 and 40 min of hydrogenation time were determined
by wide-line nuclear magnetic resonance. The Recommended Practice and standard catalyst were useful tools in evaluating activity
and selectivity of hydrogenation catalysts. 相似文献
20.
Qunhong Liu Jiangtao Yang Hongwei Zhang Hongming Sun Shuzheng Wu Bingqing Ge Rong Wang Pei Yuan 《中国化学工程学报》2022,45(5):41-50
The hydrogenation of petroleum resin (PR) is an effective process to prepare high value-added hydrogenated PR (HPR). However, the preparation of non-noble metal-based catalysts with high catalytic activity for PR hydrogenation still remains a challenge. Herein, a La promoted Ni-based catalyst is reported through the thermal reduction of quaternary NiLaMgAl-layered double hydroxides (NiLaMgAl-LDHs). The incorporation of La is beneficial to the reduction and stability of Ni particles with reduced particle size, and the increased alkalinity effectively mitigates the breakage of molecular chains of PR. As a result, the La promoted Ni-based catalyst exhibits high catalytic activity and excellent stability for PR hydrogenation. A hydrogenation degree of 95.4% and 96.1% can be achieved for HC5PR and HC9PR with less reduced softening point, respectively. Notably, the hydrogenation degree still maintains at 92.7% even after 100 hours’ reaction, much better than that without La incorporation or prepared using conventional impregnation method. 相似文献