Nanocrystalline ZSM-5(with a crystal size in the range of 20—30 nm) has been synthesized in only 20 h via the crystallization of ultra-concentrated homogeneous synthesis mixtures. The influence of low water content, use of compound surfactant, a proper crystallization time and SiO_2/Al_2O_3 molar ratio on the properties of the final nanocrystalline ZSM-5 has been studied. Especially, the use of compound surfactant has influenced some properties of nano-ZSM such as the morphology, crystal size and crystallization greatly. The nano-ZSM-5 zeolite was investigated using XRD, BET, SEM, NH_3-TPD, and other techniques. The evaluation results in a 200-mL hydrogenation unit indicated that the synthesized nano-ZSM-5 had excellent catalytic performance in diesel hydrodewaxing.
利用碳原子线(CAWs)上的羧基与2-巯基乙胺的氨基发生选择性缩合反应生成巯基化碳原子线,并用红外光谱对反应进程及一些反应条件的影响进行表征.实验结果表明:10 mg经浓硝酸氧化处理过的碳原子线在含有20 mg巯基乙胺、10 mL CH2Cl2、1 mL N(Et)3(三乙胺)、0.2 g DCC(二环己基碳化二亚胺)的液相反应体系中,60℃温度下作用24 h可完成缩合反应,生成巯基化碳原子线.在该巯基化过程中,CAWs的特征碳链结构并未发生可觉察的变化.
ZSM-5 zeolite was synthesized in a super-concentrated system using different kinds of surfactants. The ZSM-5 samples were characterized by XRD, SEM, FT-IR and BET techniques. The surfactant could change the properties of ZSM-5 zeolite, including the crystallinity, the crystal grain size, the surface area, the pore volume and the Si/Al mole ratio.
