摘要
采用超声技术制备掺钡纳米氧化镁,并以其为载体,以Ru3（CO）12为前驱体,采用浸渍法制备了一系列钌基氨合成催化剂.采用场发射扫描电镜、X射线衍射和N2物理吸附等表征手段,考察了催化剂的表面形貌、物相和表面织构性质.在400-450℃的条件下评价了催化剂对氨合成的催化活性.结果表明,以超声技术制备的掺钡纳米氧化镁有较大的比表面积和较规则的孔道结构,并增强了钡、镁之间的相互作用,使钡更均匀地分散于载体中,极大地提高了钡的促进作用,从而使其负载的钌基催化剂的活性大幅度提高.当超声作用为时间30 min时,在10 MPa,425℃和空速10 000 h-1的条件下,4%Ru/Ba-MgO催化剂上的氨合成反应速率达到61.02 mmol/（g.h）.
Ba-doped nano-magnesia （Ba-MgO） was prepared by the chemical co-precipitation method using ultrasonic technique, and a Ru catalyst was prepared using this Ba-doped nano-magnesia as the support and Ru3 （CO）12 as the Ru precursor by impregnation. The catalyst was characterized by field-emission scanning electron microscopy, X-ray diffraction, and N2 physical adsorption. The Ba-doped nano-magnesia treated with ultrasonic wave has large surface area and regular porosity, and Ba was uniformly dispersed in the support. The activity of the Ru catalyst for ammonia synthesis was evaluated under the conditions of 10 000 h-1, 10.0 MPa, and 400-450 ℃. With the promotion of Ba, the Ru catalyst supported on Ba-MgO showed high activity. When the nano-magnesia was treated with ultrasonic wave for 30 min, the reaction rate of ammonia synthesis over 4%Ru/Ba-MgO reached 61.02 mmol/（g·h） under the conditions of 10.0 MPa, 425℃ , and 10 000 h^-1.
出处
《催化学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第5期484-488,共5页
基金
国家自然科学基金(20203016)
浙江省自然科学基金(Y406294)
关键词
超声制备
钡
纳米氧化镁
钌
负载型催化剂
氨合成
ultrasonic preparation
barium
nano-magnesia
ruthenium
supported catalyst
ammonia synthesis
作者简介
霍超，女，1971年生，副研究员 联系人：霍超．Tel：（0571）88320815；E-mail：chaohc@zjut．edu．cn
