Identifying the pieces of puzzles in the very early stages of zeolite formation process:an UV Raman spectroscopic study

	Identifying the pieces of puzzles in the very early stages of zeolite formation process:an UV Raman spectroscopic study
	Fan FT(范峰滔) ; Li C(李灿)
	2011
会议名称	in‐situ molecular spectroscopic technique and application
会议日期	2011-6-20
会议地点	orleans
页码	19-0
通讯作者	李灿
中文摘要	the synthesis mechanism of zeolite has drawn much attention due to their use in oil refining, petrochemical and fine chemical industry field. understanding the synthesis mechanism of zeolite is a very interesting but challenging topic, because zeolite crystals are usually formed through complicated routes. uv raman spectroscopy is a powerful technique to characterize zeolite synthesis process because it can avoid the fluorescence interference occurring in visible raman spectra and concurrently enhances the raman signal owing to the short wavelength and resonance raman effect. in this lecture, the synthesis processes of zeolite and transition metal-containing zeolite (such as zeolite x, alpo-5, fe-zsm-5 and fe-zsm-35) have been studied with in situ raman and resonance raman techniques coupled to the home-assembled uv raman spectrograph. the synthesis mechanism of these zeolites, including the identification of primary units, assembly through key intermediates, transition metal species and organic templates in the very early stages of zeolite formation have been all well studied. the synthesis process of zeolite x and alpo-5 have been studied by in situ uv raman spectroscopy. it is found that zeolite x are formed via the assembly of 4-rings, branched units in the solid phase and monomer silicate species in the liquid phase. in the synthesis process of alpo-5, the condensation of the 4-ring species with the steric role of the organic templates results in an amorphous pre-state with channel-like structures, which subsequently transform into 3d afi architectures via the newlybuilt 6-rings. the evolutions of the zeolite framework and iron species were studied by uv raman and uv resonance raman spectroscopies during the synthesis of fe-zsm-5. the precursor contains iron atoms in distorted tetrahedral coordination and silicate rings in the early synthesis stage. nucleation via aggregation of these precursor species happened from inside out of the amorphous particles has been observed. based on the understanding of the synthesis mechanism of zeolites, the synthesis strategies of iron containing zeolite have been developed, which include assembly of tailored iron species and zeolite intermediates.
合作状况	特邀报告
会议主办者	法国国家科学研究院
会议录	studium conference
会议录出版者	待补充
会议录出版地	待补充
学科主题	物理化学
内容类型	会议论文
源URL	[http://159.226.238.44/handle/321008/116090]
专题	大连化学物理研究所_中国科学院大连化学物理研究所
推荐引用方式 GB/T 7714	Fan FT,Li C. Identifying the pieces of puzzles in the very early stages of zeolite formation process:an UV Raman spectroscopic study[C]. 见:in‐situ molecular spectroscopic technique and application. orleans. 2011-6-20.