氮化硅胶的制备及其吸收CO2性能的研究

采用二次合成法制备了氮化硅胶．考察了水量、氮化温度对氮化硅胶合成的影响。采用扫描电镜、元素分析、X-射线光电子能谱和29SiMASNMR等方法对氮化硅胶进行了袁征。结果表明：水量是影响氮化硅胶粒径大小的重要因素；随着氮化温度的升高，氮化硅胶的氮含量（质量分数）增加；在氨气流速为i00mL·min^-1、氮化温度为1000℃、氮化时间为20h的条件下，氮化硅胶的氮含量达9．48％。将氮化硅胶用于C03的吸收，与未氮化的硅胶相比，氮化硅胶对CO2有明显的吸收能力，吸收量从3．08×10^-4g·g^-1提高到6．71×10^-4g·g^-1。

Preparation of Nitrided Silica Gels and Their Absorption Performance for Carbon Dioxide

Nitrided silica gels were prepared by two-synthetic method,and the effects of water amount and nitridation temperature on the synthesis of nitrided silica gels were investigated. Several technologies such as scanning electron microscopy, elemental analysis, X-ray photoelectron spectroscopy,29 Si MAS NMR and so on were used to characterize the nitrided silica gels. The results showed that water amount was an importanfactor to the particle size of nitrided silica gels,and with the rising of nitridation temperature, the nitrogen content （mass fraction） of the nitrided silica gels increased. When the ammonia flowing rate was kept on 100 mL ·min^-1 under the nitridation temperature of 1000 ℃for 20 h,nitrogen content of nitrided silica gels reached up to 9.48%. In this paper,the nitrided silica gels were applied to the absorption of carbon dioxide. Compared to the non-nitrided silica gels,the nitrided silica gels exhibited the significantly higher absorption capacity,and the ab- sorption amount of CO2 increased from 3.08×10^-4g·g^-1 to 6.71×10^-4g·g^-1.