柠檬酸络合法制备Ba促进ZrO_2负载Ru催化剂上氨合成反应性能  

Ammonia Synthesis over Ruthenium Catalysts using Barium-Doped Zirconia as Supports Prepared by Citric Acid Method

作　　者：林建新[1] 王自庆[1] 张留明[1] 倪军[1] 王榕[1] 魏可镁[1] 

机构地区：[1]福州大学化肥催化剂国家工程研究中心,福建福州350002

出　　处：《催化学报》2012年第7期1075-1079,共5页

基　　金：中国石油科技创新基金(2010D-5006-0502);国家科技支撑计划(2007BAE08B02);福建省教育厅科技项目(JK2011005)~~

摘　　要：采用柠檬酸络合法制备了一系列不同含量Ba掺杂的ZrO2,再用浸渍法制备了K-Ru/Ba-ZrO2催化剂并将其用于氨合成反应.采用X射线衍射和CO2程序升温脱附技术考察了Ba含量对催化剂结构与性能的影响.结果表明,Ba掺入ZrO2后形成的BaZrO3有助于其负载的Ru催化剂氨合成活性的显著提高.在5.0MPa,10000h–1,425oC时,Ru/Ba-ZrO2(Ba:Zr摩尔比为1:1)催化剂活性最高,出口氨浓度和反应速率分别达9.24%和29.77mmol/(g·h).这主要归因于载体的强电子传导性能和碱性提高.Barium-promoted zirconia （Ba-ZrO2） was synthesized by the citric acid method and used as supports for Ru/Ba-ZrO2 catalysts, which were prepared by incipient wetness impregnation with K2RuO4 as precursor. The obtained Ba-ZrO2 and catalysts were characterized by X-ray diffraction and CO2 temperature-programmed desorption. The effect of Ba content on the structure and catalytic activity of K-Ru/Ba-ZrO2 catalysts is discussed. The formation of BaZrO3 can improve significantly the catalytic activity of Ru/Ba-ZrO2 for ammonia synthesis. The ammonia concentration and rate of ammonia synthesis of the K-Ru/Ba-ZrO2 catalyst （molar ratio of Ba：Zr is 1：1） were 9.24% and 29.77 mmol/（g·h）, respectively, at 425 °C, 5.0 MPa, and 10000 h–1. Improvements in electron conductivity and the basic nature of the catalyst may be the main reasons for such high catalytic activity in ammonia synthesis.

关 键 词：钡 二氧化锆 钌 氨合成 电子作用 

分 类 号：O643.32[理学—物理化学]