Abstract

The effect of the acidic characteristics of an alumina support on the properties of formed palladium particles is studied to improve the activity of catalysts for the hydrogenation of unsaturated hydrocarbons of the pyrogasoline fraction. High catalytic activity is characteristic of highly dispersed palladium particles, but the surfaces of palladium particles are blocked by unsaturated hydrocarbons, due to their electron deficiency. In this work, palladium/alumina catalysts with supports of different acidities due to chemical modification with various reagents are studied via NH₃ temperature-programed desorption, transmission electron microscopy, and X-ray photoelectron spectroscopy. The samples are subjected to catalytic tests in the butadiene-1,3 hydrogenation reaction under laboratory conditions. The catalysts on supports with acidic modifiers display low butadiene-1,3 conversion and higher selectivity toward butene-1, relative to an unmodified sample. The catalysts on the supports treated with basic additives displayed high butadiene-1,3 conversion while retaining their selectivities toward butene-1 and butane.

中文翻译：

---

丁二烯-1,3加氢反应中Pd / Al 2 O 3催化剂活性组分的高度分散颗粒的结构和电子性质

摘要

研究了氧化铝载体的酸性特征对所形成的钯颗粒的性能的影响，以提高催化剂对汽油汽油馏分的不饱和烃进行氢化的活性。高催化活性是高度分散的钯颗粒的特征，但是钯颗粒的表面由于其电子缺乏而被不饱和烃封闭。在这项工作中，通过NH ₃研究了由于用各种试剂进行化学修饰而具有不同酸度的载体的钯/氧化铝催化剂程序升温解吸，透射电子显微镜和X射线光电子能谱。在实验室条件下，将样品在丁二烯-1,3氢化反应中进行催化测试。相对于未改性的样品，带有酸性改性剂的载体上的催化剂显示出较低的丁二烯-1,3转化率和较高的对丁烯-1的选择性。用碱性添加剂处理的载体上的催化剂表现出高的丁二烯-1,3转化率，同时保持了其对丁烯-1和丁烷的选择性。