Ru/CNTs-Al_2O_3氨合成催化剂的制备与表征  

Preparation and Characterization of Ru/CNTs-Al_2O_3 Catalyst for Ammonia Synthesis

作　　者：林建新[1] 王国华[1] 王榕[1] 林炳裕[1] 倪军[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,福州350002

出　　处：《物理化学学报》2011年第8期1961-1967,共7页Acta Physico-Chimica Sinica

基　　金：国家科技支撑计划(2007BAE08B02);福州大学科技发展基金(2008-XY-7)资助项目~~

摘　　要：采用H2O2、HNO3和空气等氧化剂(ox)对碳纳米管-氧化铝(CNTs-alumina)复合材料进行纯化改性处理,制备了Ru/CNTs-alumina-ox系列催化剂.透射电镜(TEM),热重(TG),X射线衍射(XRD)和傅里叶变换红外(FTIR)光谱分析结果表明,CNTs-alumina-H2O2复合载体中碳管结晶度最好,且部分碳管被打断,长度变短,使其表面的羟基、羧基和羰基的含量明显提高.电感偶合等离子体发射光谱(ICP)分析结果还表明,经HNO3处理时CNTs-alumina-HNO3复合载体中有Al的溶出,溶液中Al含量为49.98mg.g-1.经三种氧化剂处理后所得到的催化剂,其结构和表面化学性质存在明显的差别,影响了氨合成催化剂的活性,其中以CNTs-alumina-H2O2复合载体制备的催化剂氨合成活性最高,在10MPa、425℃、10000h-1条件下,Ru/CNTs-alumina-H2O2催化剂氨合成反应速率达到39.8mmo.lg-1.h-1.The purification treatment of carbon nanotubes-alumina was carried out using various oxidizers （ox）, such as H2O2, concentrated HNO3, and air. The obtained composite was used as support for ruthenium catalysts. The structures and properties of the products before and after modification were characterized and measured using transmission electron microscopy （TEM）, thermogravimetric analysis （TG）, X-ray diffraction （XRD）, and Fourier transform infrared （FTIR） spectroscopy. The results show that purification modification treatment can remove the impurities on the surface of the CNTs-alumina, shorten the CNTs, and increase the amounts of hydroxyl, carboxyl, and carbonyl groups. Inductively coupled plasma （ICP） analysis shows that the dissolution solution composition of the CNTs-alumina composite supports with HNO3 oxidation treatment contains 49.98 mg.g-1 AI. The ammonia synthesis rate of the Ru/ CNTs-alumina-H2O2 was found to be 39.8 mmol. g-1. h-1 at 10 MPa, 10000 h-1, and 425 ℃, which was higher than those for other CNTs-alumina-ox supported Ru catalysts.

关 键 词：氧化剂 碳纳米管 氧化铝 氨合成 钌 

分 类 号：TQ113.247[化学工程—无机化工]