| Summary: | 碩士 === 中原大學 === 化學研究所 === 102 === In this study,the self-prepared room temperature ionic liquid, [Bmim][BF4] , was used as a template and TEOS as precursor to synthesize the SiO2 aerogel materials by the sol-gel method The SiO2 aerogel was then coated with a carbon layer to form a SiO2@C composite by calcination with , polyacrylonitrile
(PAN)solutions and DMAC solvent at 700oC for carbonization.
The morphology and elements ratio were examined by the SEM, TEM, EDS , FT-IR and TGA anaylses, and the BET surface area and the related parameters were obtained by the N2 adsorption/desorption measurement . Besides, the toxic hydrophilic formic acid was used as an example to investigate the efficiency
adsorption for the as-prepared SiO2@C composites.
It was found that the SiO2@C composites were successfully prepared with PAN and SiO2.the surface area, pore volume, average pore diameter and N2 adsorption volume was 187.2 m2/g , 4.81 cm3/g, 10.3nm and 314.7 cm3/g, respectively. Besides, The adsorption/desorption curves showed that the curves was type IV, indicating that the composite was basically mesoporous material. The results also indicates that the SiO2@C composite had better adsorption/desorption ability that the free active carbon, Besides,The SEM and TEM confirm that the inner part of the composite is SiO2, and the outer part iscarbon layer. Further more, the amount of the toxic hydrophilic formic acid absorbed in the SiO2@C composite measured by TGA was 0.065mole/g,which is two times higher that of the commercial active carbon. The results show that the SiO2@C composite is a potential material for application in low-concentration toxicants absorption, liquid and gas filtratio, as well as the
handling of the toxic chemicals wastes handling.
|
|---|
