催化学报

催化学报 ›› 2006, Vol. 27 ›› Issue (9): 793-798.

• 研究论文 • 上一篇    下一篇

低温固相法制备高比表面积的纳米MgO

管洪波,王培,赵璧英,朱月香,谢有畅   

  1. 北京大学化学与分子工程学院物理化学研究所分子动态与稳态国家重点实验室, 北京 100871
  • 收稿日期:2006-09-25 出版日期:2006-09-25 发布日期:2010-10-28

Synthesis of Nanometer Magnesia with High Surface Area by Solid-State Chemical Reaction

GUAN Hongbo, WANG Pei, ZHAO Biying, ZHU Yuexiang*, XIE Youchang   

  1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Physical Chemistry, College of Chemistry and Molecular Engineering , Peking University, Beijing 100871, China
  • Received:2006-09-25 Online:2006-09-25 Published:2010-10-28

PDF

1029

被引次数

92

摘要： 以草酸和乙酸镁为原料,采用低温固相化学反应合成出前体MgC2O4·2H2O, 再通过焙烧得到纳米MgO. 采用X射线衍射、 N2物理吸附、透射电镜和热重-差热技术对前体和MgO样品进行了表征,并考察了焙烧气氛的影响. 结果表明,在流动干燥的氮气中520 ℃焙烧4 h后制得了比表面积高达412 m2/g的纳米MgO; 此MgO为面心立方结构,晶粒尺寸为4～5 nm, 粒子堆积成在一定程度上长程有序的介孔结构,并具有十分优良的抗高温烧结性能, 600和800 ℃焙烧2 h后,其比表面积仍分别高达357和153 m2/g.

关键词: 纳米氧化镁, 草酸, 乙酸镁, 固相反应, 高比表面积

Abstract: Nanometer MgO samples with high surface area, small crystal size, and mesoporous texture were synthesized by thermal decomposition of MgC2O4•2H2O, which was prepared by solid-state chemical reaction between H2C2O4•2H2O and Mg(CH3COO)2•4H2O. The existence of steam accelerated the sintering of MgO during the decomposition process and MgO with surface area as high as 412 m2/g was obtained through calcining the precursor in flowing dry nitrogen at 520 ℃ for 4 h. The samples were characterized by X-ray diffraction, N2 adsorption, transmission electron microscopy, thermogravimetry, and differential thermal analysis. The as-prepared MgO was composed of nanocrystals with a size of 4-5 nm and formed a wormhole-like porous structure. In addition, the MgO had good thermal stability, and its surface area was still 357 and 153 m2/g after calcination at 600 and 800 ℃ for 2 h, respectively. Compared with the MgO sample prepared by the precipitation method, MgO prepared by the solid-state chemical reaction has similar pore size distribution, surface area, and crystal size. The solid-state chemical method has the advantages of low cost, low pollution, and high yield; therefore it appears to be a promising method for the manufacture of nanometer MgO in industry.

Key words: nanometer magnesia, oxalic acid, magnesium acetate, solid-state chemical reaction, high surface area