纳米分子筛的合成及硫化氢吸附性能

利用无模板水热法合成纳米尺寸的小孔SOD型和大孔X型分子筛, 并考察了其硫化氢脱除性能. 通过对比两种分子筛的硫化氢吸附性能, 证实分子筛对硫化氢的吸附主要集中于孔道内和可及的活性位. 考察了晶粒尺寸、 体积空速和吸附温度等因素对硫化氢吸附的影响, 发现纳米尺寸X型分子筛具有更大的硫容, 并且在低温和低空速下分子筛中的硫化氢分子易于脱除. 随后对纳米X型分子筛进行了金属离子交换改性, 发现Cu改性的分子筛硫容优于其它离子改性的吸附剂, 能达到20.6 mg/g. NaX-N和Cu-NaX-N再生后的硫容分别为新鲜分子筛的62.4%和78.5%.

Synthesis of Nano-zeolite and Its Adsorption Performance for Hydrogen Sulfide

Nanosized SOD type and X-type zeolites were synthesized by the free-template hydrothermal method， and the hydrogen sulfide removal performance was investigated. By comparing the hydrogen sulfide adsorption performance of the two kinds of zeolite， it was confirmed that the adsorption of hydrogen sulfide in zeolite was mainly concentrated in the pores and accessible active sites. The influences of volume space velocity and adsorption temperature as well as the size of zeolite on hydrogen sulfide adsorption were deduced. It is found that nano-sized X zeolite has larger sulfur capacity， and the zeolite is easy to remove hydrogen sulfide molecules at low temperature and low space velocity. Then， the metal supported molecular sieves were obtained by ion exchange. The sulfur capacity of Cu-NaX-N can reach 20.6 mg/g， better than that of other ion modified adsorbents. The sulfur capacity of regenerated NaX-N and Cu-NaX-N zeolites can reach 62.4% and 78.5% of that of fresh zeolite， respectively.