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1.
镁铝尖晶石的制备及其催化降烯烃性能研究   总被引:1,自引:0,他引:1  
采用溶胶-凝胶法制备出一种可以降低催化裂化(FCC)汽油烯烃含量的镁铝尖晶石催化助剂,在小型固定床反应装置上考察了其催化降烯烃效果,并对镁铝尖晶石的制备条件和不同镁铝的物质的量比对降烯烃效果的影响进行了研究,对助剂的催化降烯烃机理进行了分析.实验结果表明,制备温度为80℃,镁铝的物质的量比为1:1时,助剂可将烯烃的体积分数降低20%以上.助剂的降烯烃活性主要是晶胞常数最大的MgAl2 O4·MgO尖晶石促进了氢转移反应.  相似文献   

2.
陈立谦  韩冰  刘琦 《无机盐工业》2011,43(12):38-41
采用共沉淀法合成镁铝及镁锌铝水滑石,并通过X射线衍射(XRD)、红外光谱(FT-IR)、扫描电镜(SEM)、热分析(TG/DTG)、粒度分析等手段对合成的水滑石进行表征,研究不同镁、铝、锌的投料比例对合成的水滑石结构及热性能等的影响。XRD表征结果表明,合成产物均具有水滑石特征峰。合成的镁铝水滑石随着镁铝比的增加其层板间距增大,层板上原子密度降低;合成的镁锌铝水滑石随着锌含量的提高层板间距减小,层板上原子密度降低。镁铝水滑石热分解过程有两个明显阶段,层间结晶水先脱除,随后是层间阴离子脱除及层板上部分羟基脱水;镁锌铝水滑石热分解过程只有一个明显的阶段,层板间阴离子在层板间结晶水脱除的同时也在脱除。  相似文献   

3.
基于催化裂化催化剂降烯烃方面的研究进展,在现有催化裂化金属钝化剂的基础上,围绕提高氢转移活性,提出制备降烯烃催化裂化助剂的技术路线,并研制开发了新型降烯烃催化裂化助剂。实验结果显示,降烯烃助剂不仅具有良好的抗重金属污染的特性,而且能有效地降低汽油中的烯烃含量,其具有较高的氢转移活性,可协调芳构化与氢转移反应,同时也改善了催化裂化产品分布。  相似文献   

4.
王小丰  王昕  施力 《工业催化》2005,12(Z1):53-55
通过实验室微型床反应器,评价了FCC汽油脱硫、降烯烃多功能复合助剂ROA脱硫和降烯烃效果.为进一步确定其工业应用性,进行了中试研究.研究发现,在加入助剂后,FC℃汽油馏分中硫含量降低了200×10-6,烯烃含量降低了9个百分,点,同时辛烷值上升了近0.8个单位.考察了助剂的稳定性,符合工业应用要求.  相似文献   

5.
概述了FCC汽油的特点,分析了FCC汽油降烯烃的方法应该具有的技术特征,介绍了FCC汽油降烯烃催化剂和助剂的开发应用情况,重点介绍了降低汽油烯烃含量的FCC新工艺,主要是MGD工艺、MIP工艺、FVI工艺、TSRFCC工艺和FDFCC工艺等。  相似文献   

6.
催化裂化汽油降烯烃技术的工业应用   总被引:1,自引:0,他引:1  
高军 《天津化工》2006,20(5):53-56
为降低汽油烯烃含量、适应清洁汽油的要求,锦州石化公司先后将LGO-A降烯烃助剂、LBO-16降烯烃催化剂以及MGD工艺在三催化装置上成功地进行了工业应用。降烯烃助荆和降烯烃催化剂的开发利用是投入少、见效快的方法,而投用MGD工艺,可使汽油烯烃含量下降的更多。  相似文献   

7.
采用成核晶化隔离法合成了锂铝、镁铝、锌镁铝及锌铝类4种类水滑石。通过水化热、X射线衍射、Fourier红外光谱、热重–差热分析和抗压强度测试等研究了4种纳米类水滑石对硫铝酸盐水泥熟料水化及其强度的发展规律。结果表明:类水滑石的添加均能促进硫铝酸盐水泥熟料的早期水化,没有改变水化产物的种类,但增加了水化产物的数量,提高了1、3、7、28和60 d的抗压强度;类水滑石的化学组成影响其对硫铝酸盐水泥熟料的水化及增强能力,且其大小顺序依次为锂铝类水滑石、镁铝类水滑石、锌镁铝类水滑石及锌铝类水滑石。  相似文献   

8.
借助分子模拟手段,研究了锌、镧、镁掺杂改性对钙铝基复合型金属氧化物催化酯交换的影响。构建了Al2O3(110)、CaO(100)以及锌、镧、镁掺杂改性的衍生模型。计算了不同改性氧化铝表面的掺杂结合能,分析了甲醇和乙酸甲酯在氧化钙及其衍生物表面的吸附过程,讨论了甲醇在Al2O3(110)及其衍生物表面的吸附过程及其Mulliken电荷密度的变化。结果表明,采用锌、镧、镁掺杂改性能强化钙铝复合型金属氧化物催化剂对甲醇的吸附性能,有助于催化酯交换反应的进行。  相似文献   

9.
介绍了碱液、黄油抑制剂、压缩机阻聚剂、除氧剂等几种助剂在某煤制烯烃项目烯烃分离装置中的应用及国产化进程。针对煤制烯烃工厂与传统乙烯装置的不同之处,对助剂的使用情况进行评估。分析了烯烃分离装置使用不同助剂时实际的工艺参数和各项数据、指标,比较了不同型号助剂的使用效果。评估工作在保证装置正常运行的前提下进行,优化了助剂在烯烃分离装置中的使用,降低了生产运营成本。  相似文献   

10.
章伟  宋宝东 《工业催化》2006,14(3):68-70
开发了高辛烷值型降烯烃催化裂化助剂LBO-A工业化生产技术,介绍A、B两种组分的工业化生产工艺制备过程和专有技术。采用催化剂的“组装”技术,将A、B两种性能不同的组分按照一定比例进行复配,在汽油辛烷值不变的前提下,可以有效降低FCC装置所产汽油的烯烃含量。  相似文献   

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12.
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.  相似文献   

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14.
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.  相似文献   

15.
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.  相似文献   

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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.  相似文献   

19.
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.  相似文献   

20.
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。  相似文献   

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