(江蘇大學(xué) 化學(xué)化工學(xué)院，鎮(zhèn)江 212013)
摘 要: 以硅酸鈉、氯化鈷等無機(jī)鹽為原料，通過水熱法合成含有不同Co含量的六方介孔分子篩Co-MCM-41。采用X射線粉末衍射、紅外光譜、等離子發(fā)射光譜、程序升溫還原、透射電子顯微鏡和N2吸附−脫附等技術(shù)對(duì)樣品的物化性能進(jìn)行表征，研究所合成的Co-MCM-41的穩(wěn)定性。研究結(jié)果表明：在水熱條件下合成4種不同Co含量的Co-MCM-41介孔分子篩，其比表面積為809.8~1257.2 m2/g，平均孔徑為2.7~2.8 nm。隨著介孔分子篩中Co含量的增加，介孔分子篩的比表面積、孔體積變小，介孔有序性變差。所合成的含Co介孔分子篩經(jīng)750 ℃焙燒3 h后介孔結(jié)構(gòu)被破壞，經(jīng)100 ℃水熱處理5 d后樣品雖然具有介孔結(jié)構(gòu)，但介孔有序性差。
關(guān)鍵字: Co-MCM-41介孔分子篩；水熱法；合成；穩(wěn)定性；表征
Co-MCM-41 mesoporous molecular sieves
（School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China）
Abstract:Hexagonal Co-MCM-41 mesoporous molecular sieves with different contents of cobalt were synthesized by hydrothermal method and using sodium silicate and cobalt chloride as raw materials. The physicochemical properties of the samples were characterized by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), inductive coupled plasma (ICP) technique, temperature programmed reduction (TPR), transmission electron microscopy (TEM) and N2 physical adsorption, respectively, to investigate the thermal and hydrothermal stabilities of the Co-MCM-41 samples. The experimental results show that Co-MCM-41 mesoporous molecular sieves are successfully synthesized under hydrothermal condition, with specific surface area in the range of 809.8−1257.2 m2/g and average pore size in the range of 2.7−2.8 nm. Specific surface area and pore volume of the synthesized Co-MCM-41 mesoporous molecular sieve decrease with the increase of cobalt content doped, and the mesoporous ordering becomes poor. The results of thermal and hydrothermal tests show that the mesostructure of Co-MCM-41 mesoporous molecular sieve after calcination at 750 ℃ for 3 h is damaged. On the other hand, the framework of Co-MCM-41 mesoporous molecular sieve still retains after hydrothermal treatment at 100 ℃ for 5 d, but the mesoporous ordering is poor.
Key words: Co-MCM-41 mesoporous molecular sieve; hydrothermal method; synthesis; stability; characterization
