以环己胺为模板剂的ZSM－35分子筛的合成及其催化性能

 采用环己胺为有机模板剂成功地合成出ZSM－35分子筛．反应釜的转速对ZSM－35的晶化过程有明显的影响．NH3－TPD结果显示ZSM－35的酸性分布与ZSM－5分子筛类似，但ZSM－35具有强于ZSM－5的酸性中心．酸碱浸泡试验及热分析结果表明ZSM－35具有良好的耐酸碱性和热稳定性．在连续流动的固定床反应装置上，将担载少量镍的ZSM－35分子筛催化剂用于催化裂化汽油的加氢异构化反应，结果表明，Ni／ZSM－35催化剂可降低汽油中的烯烃含量，增加异构烷烃和芳烃的含量，从而提高汽油的质量．

Synthesis of ZSM-35 Zeolite Using Cyclohexylamine as Organic Template and Its Catalytic Performance

The ZSM-35 zeolite was successfully synthesized using cyclohexylamine as the organic template and characterized by means of X-ray powder diffraction (XRD), scanning electron microscopy (SEM), temperature-programmed desorption of ammonia (NH 3-TPD) and differential thermal analysis (DTA). The XRD patterns showed that there was little difference between the as-made ZSM-35 zeolite and the calcined one, which was attributed to the function of the organic template. The crystallization curves indicated that the rotation speed of the autoclave had an obvious effect on the crystallization process of the ZSM-35 zeolite. At a relative high rotation speed (100 r/min) of the autoclave, the induction period of the ZSM-35 formation was very short, and the relative crystallinity of ZSM-35 reached 100% quickly. When the rotation speed was low (30 r/min), the induction period of the ZSM-35 formation was increased obviously, and the crystallization process was completed gradually with the prolonged time of reaction. For the ZSM-35 and ZSM-5 zeolites with the same molar ratio of SiO 2 to Al 2O 3, their acidic distribution was similar, but the ZSM-35 zeolite possessed stronger acidity than the ZSM-5 zeolite. ZSM-35 had a good resistance not only to heat but also to acid and alkali. In addition, the catalytic performance of the prepared Ni/ZSM-35 catalyst for the hydroisomerization of FCC gasoline was investigated in a continuous-flow fixed-bed apparatus. The results exhibited that this catalyst could reduce the content of olefins (from 43.25% to 30.33%) and increase the content of isoparaffins (from 22.33% to 30.18%) and aromatic hydrocarbons (from 16.60% to 20.24%).