TS分子筛的催化氧化性能研究

用自掣是四丙基溴化铵（ＴＰＡＢｒ）部分取代四丙基氢氧化铵（ＴＰＡＯＨ）为模板剂,在Ｎａ＾＋离子存在下,合成出结构优良的ＴＳ－１分子筛。在丙烯Ｈ２Ｏ２氧化制环氧丙烷反应中,考察了合成的ＴＳ－１分子筛的催化活性,催化剂的预处理。用量、利用次数、再生和反应温度与时间对反应的影响。研究表明,不同的模板和合成条件明显影响分子筛的晶粒大小。晶粒度为０．４￣０．７μｍ的ＴＳ－１分子筛经１０％ＮＨ４Ａｃ预处理后,     

Study on Aromatization of C6 Aliphatic Hydrocarbons on ZRP Zeolite Catalyst

The performance of ZRP zeolite catalysts for aromatization of C6 aliphatic hydrocarbons was investigated in a pulsed microreactor. The influence of metal modified ZRP zeolites on aromatization reaction was also studied, coupled with comparison of aromatization tendencies of olefins, paraffins and paraffins with different degrees of chain branching. Test results had shown that the lower the silicon/aluminum ratio in the ZRP zeolite, the higher the aromatization reactivity of aliphatic hydrocarbons. Modification of ZRP zeolite by zinc and its zinc content had apparent impact on the yield and distribution of aromatics. The aromatization tendency of olefins was apparently better than paraffins, while the aromatization tendency of monomethyl paraffins was better than that of straight-chain paraffins with the exception of dimethyl paraffins, which had worse aromatization tendency because of their steric hindrance.     

Study on Synthesis and Catalytic Performance of Hierarchical Zeolite

A kind of hierarchical zeolite catalyst was synthesized by hydrothermal method. X-ray diffraction （XRD） and nitrogen adsorption-desorption method were used to study the phase and aperture structure o（ the prepared catalyst. Infrared （IR） spectra of pyridine adsorbed on the sample showed that the hierarchical zeolite really had much more Bronsted and Lewis acidic sites than the HZSM-5 zeolite. The catalytic cracking of large hydrocarbon molecules showed that the hierarchical zeolite had a higher catalytic activity than the HZSM-5 zeolite.     

^29Si and ^1H High—Resolution NMR Investigation on the Hydrolysis of TEOS in TS—1 Synthesis

The ^Si and ^1H high-resolution liquid-phase NMR has been used to investigate the hydrolysis process of the tetraethyl orthosilicate(TEOS).^1H-NMR spectroscopy shows that the hydrolysis of TEOS in TPA is faster than in TEA.The impacts of TPA and TEA on the TOES hydrolysis process and its hydrolyzed product distribution have been observed by ^29Si-NMR respectively.The influences of water and the isopropyl alcohol on hydrolysis have also been diseussed.The presence of TBOT marks an evident differentiation between TPA and TEA for hydrolysis in ^29Si-NMR spectra.     

The Effect of Non-Framework Aluminum on the Stability and Activity of REY Zeolite

The present study is focused on the influence of a routine step, washing, following the preparation of calcined rare earth exchanged Y zeolite, on its hydrothermal stability. The hydrothermal stability of REY products, which were washed by different reagents, was observed and characterized by XRD, ICP, NMR, etc. The results reveal that the amount and the chemical type of the acidic media used for washing can significantly influence the content of remaining non-framework aluminum （NFA） and consequently further affect the hydrothermal stability of the washed REY products. The content of remaining non-framework aluminum can be well correlated with the crystallinity of REY products.     

Study on Filtration Performance of Silica／Alumina Slurry in the Process of Recycling Mother Liquor of NaY Zeolite

In order to recover the SiO2 contained in the mother liquor in the course of NaY zeolite synthesis to minimize pollution, the influence of various preparation conditions on the filtering velocity of gel slurry was studied using the SiO2/Al2O3 gel recovered from the NaY mother liquor in the laboratory. The results of study had shown that at a SiO2/Al2O3 ratio in the feed equating to 9:1 the SiO2 recovery rate and Al2O3 utilization rate were high with a faster flow velocity of the filtrate. The pH value of the system had great impact on the flow velocity of filtrate. Between the two methods for regulating the pH value, the one for formation of silica/alumina gel slurry by addition of sulfuric acid prior to adding aluminium sulfate in the solution could secure a faster filtration velocity. The filtration velocity was decreased in tandem with increasing SiO2 concentration in mother liquor, meanwhile an increase in dry filter cake yield.     

Synthesis and Characterization of Hollow Titanium Silicalite Zeolite（HTS）

29Si-NMR and 1H-NMR were used to follow up the basic hydrolysis of tetraethyl orthosilicate （TOES） and the results showed that species of monomer, dimer, trimer, cyclic and polymer silicates were formed. The monomer and dimer were favorable for the high activity of zeolite. XRD, 13C CP/MAS and 29Si NMR were used to trace the crystallization process of hollow titanium silicalite zeolites （HTS）. The results showed that the induction period of HTS was 80 min, and subsequently it took next 10 min to form HTS and the remaining time of the crystallization period might function for cleaning up the pores and/or washing off the impurities from the HTS zeolite. The catalytic oxidation performance of HTS zeolite is different from that of the acid activity of zeolite in which the conventional definition of crystallinity does not reflect the catalytic oxidation activity proportionally. The synthesized HTS samples were character- ized by XRD, FT-IR, UV-Vis and Raman spectra. It was confirmed that Ti was incorporated into the zeolite framework. The synthesized HTS samples revealed good repeatability and high activity for oxidation of phenol into diphenol.     

Synthesis of La-Modified Ultra Stable Zeolite L and Its Application to Catalytic Cracking Catalyst

A new type of zeolite La-USL (ultra stable zeolite L (zeolite USL) modified by La), which has superior activity, stability and selectivity in catalytic cracking of hydrocarbons and thus can be used as an active catalyst component, is reported in this paper. The zeolite L with relative crystallinity of above 90% was synthesized by the hydrothermal crystallization method under optimum conditions and characterized by means of XRD, NH3-TPD and isotherm adsorption techniques. The in-situ synthesized zeolite L with a SiO2/Al2O3 mole ratio of 5-6 was modified by cation ion exchange, hydrothermal dealumination and chemical modifications with La in order to prepare La-containing USL with a higher framework SiO2/Al2O3 mole ratio of 15-30. The modified zeolite La-USL was used as an active additive component of fluid catalytic cracking (FCC) catalyst and the resulting catalysts were evaluated by microactivity test (MAT) and fixed-fluidized bed (FFB) experiments using heavy oil as feedstock. The influence of La content in La-USL on cracking product distribution, gasoline group composition and research octane number (RON) was investigated. The results showed that when La content in La-USL was 0.8 wt%, the addition of the corresponding La-USL could result in a FCC catalyst that produced significant improvement in product distribution and gasoline quality.     

Secondary Synthesis of Ti-containing Zeolite

ＳｅｃｏｎｄａｒｙＳｙｎｔｈｅｓｉｓｏｆＴｉｃｏｎｔａｉｎｉｎｇＺｅｏｌｉｔｅＷａｎｇＸｉａｎｇｓｈｅｎｇａｎｄＧｕｏＸｉｎｗｅｎ（ＩｎｓｔｉｔｕｔｅｏｆＩｎｄｕｓｔｒｉａｌＣａｔａｌｙｓｔｓ，ＤａｌｉａｎＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏｌｏｇ...     

HZSM-5分子筛催化剂的硅铝比对醛氨缩合的影响

采用BET、FT—IR、XRD、29Si—NMR、27A1—NMR等分析手段，研究了不同硅铝比的HZSM—5分子筛微观结构及其在醛氨缩合中的催化性能。结果表明，不同硅铝比的HZSM-5分子筛，在FT-IR谱图约1219，1102，950，799，447cm^-1处有差异；在29Si—HMR谱中存在2个峰，A峰(—113．4)往高化学位移方向移动，B峰(—109．7)逐渐减弱直至消失；在27A1—HMR谱中存在1个峰，此峰(55．3)往低化学位移方向移动。醛氨缩合反应用HZSM—5分子筛催化剂的最适宜硅铝比范围在90-170之间，在此催化剂上合成烷基吡啶，收率可达89．8％。     

无黏结剂沸石分子筛的制备和应用进展

对无黏结剂沸石分子筛的制备和应用进展进行了综述,介绍了无黏结剂沸石分子筛的3种制备方法:液固相转化法、气固相转化法和组装成型法,概述了无黏结剂沸石分子筛在吸附分离、离子交换、催化反应以及生物大分子分离等领域的应用状况,探讨了今后无黏结剂沸石分子筛在优化制备工艺、改善机械强度、拓展应用和提高性能等方面的研究重点。     

低排放合成法制备NaY分子筛

采用低排放合成方法制备NaY分子筛 ,提高了合成分子筛中SiO2 的利用率 ,减少母液排放量 ,提高单釜产率 ,而所得NaY分子筛质量与常规方法相当。     

沸石分子筛技术展望

近年来国内外沸石分子筛技术发展很快,重点介绍几种新型沸石分子筛技术,ＺＳＭ－５分子筛的改进,ＭＣＭ－４１大孔分子筛、沸石分子筛膜、磷硅铝分子筛及硅钛分子筛、阐述国内研究和开发新型分子技术的方向。     

在复杂水热合成体系下制备K-ZSM-5沸石分子筛

以生物质气化电厂废弃稻壳灰(RHA)为原料,通过KOH溶液水热处理制取RHA硅溶胶,研究MFI分子筛晶体在复杂合成液体系中的生长习性.考察了在复杂合成体系中,模板剂种类、模板剂用量、Si/Al比、晶化温度、晶化时间等因素对K-ZSM-5分子筛合成过程的影响规律.结果表明,以废弃RHA为原料,采用结构导向作用较强的TPABr模板剂,可在较宽Si/Al摩尔比范围(30～2002)内合成出K-ZSM-5分子筛.所制备的分子筛产品结晶度高、晶形完备、具有丰富的微孔结构、较大的比表面积和优良的热稳定性,具备了用做工业催化剂和吸附剂的基础.     

超稳Y沸石的制备条件改进及其性能研究

对(NH_4)_2SiF_6脱铝补硅制备超稳Y沸石的制备条件和机理进行了探讨,并改进了制备条件和产品的水热稳定性。结果表明,脱铝通常比补硅速度快;用价廉易得的NH_3·H_2O或NH_3·H_2O-(NH_4)_2SO_4替代NH_4Ac缓冲剂同样可制得优质超稳Y产品;制备中加入硅溶胶可提高最终产品的水热稳定性。改进的超稳Y沸石的活性和动态活性均高于传统的USY催化剂。     

NO分解催化剂Cu/分子筛的ESR研究 Ⅰ.水合铜分子筛的ESR研究

系统地比较了在各种不同制备条件下制得的Ｃｕ／ＺＳＭ－５、Ｃｕ／丝光沸石、Ｃｕ／镁碱沸石和Ｃｕ／毛沸石的ＥＳＲ谱，至少六种水合Ｃｕ物种被发现，而且发现分子筛的腔结构对Ｃｕ物种的存在状态有很大的影响。     

分子筛择形催化作用理论和应用的新进展

从分子筛的反应物择形、过渡态择形、产物择形、笼效应、孔嘴择形催化等方面综述了分子筛择形催化作用的研究进展,对分子筛类型和择形功能进行了总结,分析了分子筛择形催化在石油化工领域中应用的新机遇。