粉煤灰无溶剂法合成方钠石新方法及效果验证

粉煤灰因具有高硅铝含量、低硅铝比的特性常用来合成低硅纯相方钠石。为提高粉煤灰的高值化利用,以粉煤灰为原料,采用无溶剂法合成方钠石,考察灰碱比、晶化时间和晶化温度对方钠石物相组成、微观结构以及结晶度的影响。结果表明,在灰碱比为1∶0.8(质量比)、晶化时间为9 h、晶化温度为160℃的工艺下,可合成类型单一、结晶度高的方钠石,灰碱比对相对结晶度的影响显著。合成的方钠石具有微孔和介孔复合孔结构,其N₂吸附-脱附等温线为典型的IV型等温线,具有III型回滞环。方钠石的铝含量高,具有良好的热稳定性。相较于水热法合成方钠石,本实验方法粉煤灰利用率高,为粉煤灰利用提供了新途径。     

低Na_2O/Al_2O_3比凝胶一步晶化法合成高硅小晶粒NaY分子筛

NaY晶体的n(Na_2O)∶n(Al_2O_3)=1.0,但现有NaY合成工艺的起始凝胶的n(Na_2O)/n(Al_2O_3)均较高,导致大量原料中的Na_2O及相应量其他组分没有转化为产品,而是进入晶化母液被滤除,因此NaY生产企业期望采用更低n(Na_2O)∶n(Al_2O_3)的凝胶来提高NaY合成收率。对起始凝胶Na_2O与Al_2O_3物质的量比为3.84~4.64的水热合成NaY分子筛做了研究。结果表明,在100℃以下晶化时,n(Na_2O)∶n(Al_2O_3)=3.84的低碱度凝胶不能晶化出NaY分子筛;在100℃以上晶化时,n(Na_2O)∶n(Al_2O_3)=3.84的低碱度凝胶能够晶化出结晶度、硅铝比(Si O2与Al_2O_3物质的量比,下同)均较高且无杂晶的NaY。其最佳的晶化条件:晶化温度为110℃、晶化时间为30 h。并可重复制备出平均结晶度为95%、平均骨架硅铝比为5.93、典型粒径约为1μm的小晶粒NaY分子筛,原料平均转化率达68.2%。     

类固相法快速合成小颗粒方沸石的研究

为解决传统水热法合成方沸石工艺存在晶化时间长、体系水含量大等弊端,采用类固相法以硅铝干凝胶为硅源和铝源、氢氧化钠为碱源,进行了快速合成小颗粒方沸石的研究,并通过X射线衍射(XRD)、扫描电镜(SEM)、红外光谱分析(FRIR)、激光粒度分析等手段对合成产品进行了表征分析。结果表明,当晶化时间t=8 h,晶化温度T=150℃,硅铝干凝胶的摩尔组成n(SiO_2)/n(Al_2O_3)=5,晶化体系物料摩尔组成n(Na_2O)/n(SiO_2)=0.26,n(H_2O)/n(SiO_2)=11.10时,可合成出形貌均一、结晶良好的小颗粒方沸石,其粒径大小主要集中在0.1～20mm。与传统水热法相比,该方法极大地减少了合成过程的用水量,缩短了晶化时间,缩小了产品粒度,从整体上优化了方沸石的合成工艺。     

高岭土微球上晶种法原位合成ZSM-5分子筛的研究

以HZSM-5为晶种,水热条件下考察在高岭土微球上原位晶化合成ZSM-5分子筛的碱硅比、水硅比、晶化时间、晶化温度、晶种投入量和投料硅铝比等合成条件对晶化产物的影响,并对合成的ZSM-5进行了表征。结果表明,在晶化温度170 ℃、投料硅铝比90~150、晶种投入量10%、碱硅比0.15~0.2和水硅比20的条件下晶化一定时间,在高岭土微球上成功合成出粒径（1~2） μm、结晶度40%的ZSM-5分子筛晶体。     

模板剂法水热合成高硅铝比ZSM-5分子筛

以工业水玻璃和硫酸铝为主要原料,正丁胺为模板剂,利用水热法合成出了高硅铝比ZSM-5分子筛。考察了晶化时间、晶化温度、投料硅铝比、合成体系pH值以及模板剂用量等因素对晶化产物的影响。采用X射线衍射、傅里叶变换红外光谱、低温氮气吸脱附、核磁共振、扫描电子显微镜等手段对合成样品进行了表征。结果表明:合成ZSM-5分子筛最适宜的条件为:晶化时间36h,晶化温度170℃,投料硅铝比200,合成体系的pH=11.0,模板剂加入量为模硅比0.2。在最适宜条件下合成得到的ZSM-5分子筛产物具有高的相对结晶度,BET比表面积为335m2/g,晶粒尺寸约为5μm×15μm,骨架硅铝比大于100。     

动态条件下ZSM-12分子筛的合成

采用动态晶化法,系统考察了硅源、硅铝比、模板剂含量以及水含量对ZSM-12分子筛合成的影响,得到合成纯相ZSM-12分子筛的最佳条件为:硅溶胶为硅源,n(Si)/n(Al)=45~70,n(四乙基氢氧化铵,TEAOH)/n(SiO_2)=0.14,n(H2O)/n(SiO_2)=13。通过XRD、SEM、BET、NH3-TPD对所合成的产物进行了表征。体系中的硅铝比对所合成产物的晶相和晶化动力学有显著影响:当硅铝比(Si/Al摩尔比,下同)过低时,容易导致MFI和BEA结构的杂晶相的生成;硅铝比较高时,动态晶化比静态晶化更有利于提高分子筛的合成效率;体系中的n(TEAOH)/n(SiO_2)和n(H_2O)/n(SiO_2)会在很大程度上影响所合成产物的晶相和形貌。     

焙烧高岭土水热合成高硅铝比小晶粒NaY分子筛

采用不同温度对高岭土进行焙烧活化,以焙烧高岭土为原料,在水热条件下直接法合成了高硅铝比小晶粒NaY分子筛.考察了晶种胶添加量、高土/偏土比例以及投料硅铝比对晶化过程和产物性质的影响.研究结果表明,在晶种胶添加量为14wt％、高土/偏土比例为1及投料硅铝比为15.0的条件下,以焙烧高岭土为原料合成的NaY样品的相对结晶度为77％,骨架硅铝比高达6.3,晶粒尺寸为300 ～ 600 nm.重油催化裂化性能评价结果表明,以高岭土合成NaY样品制备的催化剂DUT-E,具有优异的重油催化裂化活性(93.6％),高汽油收率(56.8％)及很低的焦炭产率(3.1％).     

低硅铝比EU-1沸石的合成与表征

对合成低硅铝比n(Si O2)/n(Al2O3)EU-1沸石过程中的硅源、晶化时间以及硅铝比进行了研究,研究结果表明:硅源选择硅溶胶最合适,硅铝比可以低到20,硅铝比为20的EU-1沸石的晶化时间为65 h即可,延长晶化时间对产品没有太大影响。以标准的EU-1沸石作为参考,对合成的硅铝比为20的EU-1沸石做了X-射线衍射(XRD)、红外光谱(FT-IR)、扫描电镜(SEM)和低温N2吸附-脱附等表征,结果表明:该法合成的硅铝比为20的EU-1沸石具有较好的结晶度,晶体形貌规整,具有适中的比表面积,孔结构发达,微孔和介孔分布比较均一。     

硅铝胶气相法合成MCM-22分子筛工艺条件的影响

以硅酸和偏铝酸钠为硅源和铝源制备硅铝胶,采用气相法合成MCM-22分子筛.考察了硅铝比、钠离子含量、模板剂六亚甲基亚胺(HMI)和水用量等工艺条件对合成的影响.结果发现,与水热晶化法相比,气相法合成中硅铝比范围变窄,所需Na 含量大大降低,合成的MCM-22分子筛结晶更完整,晶粒直径较大.原料组成为SiO2:(0.02～0.033)Al2O3:(0.085～0.1)Na :1.2HMI:20H2O,晶化温度和时间分别为150 ℃和5～7 d的实验合成条件较为适宜.     

硅酸盐熔体结构对煤灰黏温特性调控研究进展

通过改变硅酸盐熔体结构对煤灰黏温特性进行调控,对气流床气化意义重大。在对硅酸盐熔体结构和黏温特性影响因素(灰渣成分、临界黏度温度、熔体结晶和气氛)分析的基础上,对单一添加剂(SiO_2、CaO、Na_2O和Fe_2O_3)和煤灰组成关联比(硅铝比SiO_2/Al_2O_3、钙铁比CaO/Fe_2O_3、钙钠比CaO/Na_2O和钾钠比K_2O/Na_2O)对煤灰黏温特性的影响及其机理进行了系统的阐述。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。