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1.
王树清  高崇 《化工文摘》2006,(3):33-34,36
以丁酸、正己醇为原料,直接酯化合成丁酸己酯,分别研究了反应温度、反应时间、原料配比、带水剂、催化剂用量等条件对合成反应的影响,确定了最佳工艺条件。该方法合成丁酸己酯的最佳工艺条件是:反应温度120℃、反应时间3.5h、n(正己醇):n(丁酸)为1.2、催化剂用量为2.32%、带水剂环己烷为15mL(丁酸为0.2mol的情况下)。丁酸己酯的收率达到95.86%。催化剂不经处理可循环使用多次。该催化剂具有价廉易得、催化活性好、不腐蚀设备、无环境污染等优点。  相似文献   

2.
甲基磺酸钙催化酯化反应性能的研究   总被引:10,自引:1,他引:9  
王敏  姜恒  宫红  苏婷婷  刘立军 《化学试剂》2004,26(4):201-203,236
合成了甲基磺酸钙,并用热重和EDTA络合滴定法对其进行了分析。研究了以甲基磺酸钙为催化剂催化氯乙酸与异丙醇的酯化反应中各种因素对酯化率的影响,当醇酸物质的量比1.2:1,催化剂用量1.0%(以酸的物质的量计),反应时间2.5h,反应温度80~85℃,环己烷作为带水剂时,酯化率可达98.1%。用甲基磺酸钙作催化剂合成其他氯乙酸酯,酯化率均在95.0%以上。催化剂甲基磺酸钙可重复使用。  相似文献   

3.
活性炭固载对甲苯磺酸催化合成乙酸异戊酯   总被引:5,自引:0,他引:5  
研究了用颗粒状活性炭固载对甲苯磺酸作催化剂,在优化条件下催化合成乙酸异戊酯。实验结果显示:催化剂用量为0.3g,n(醇):n(酸)=1.2:1,用环己烷作带水剂加热,在油浴温度为130--135℃下,回流90min时,酯化率为99.50%以上。  相似文献   

4.
曹永军 《应用化工》2011,40(6):978-980,984
制备了WO3为活性组分、TiO2为载体的双金属固体酸酯化催化剂WO3/TiO2,用于正丁酸与正己醇酯化合成正丁酸己酯,考察了催化剂中WO3含量、焙烧温度、催化剂用量、n(正己醇)∶n(正丁酸)、反应时间和催化剂重复使用性等因素对酯化率的影响。实验结果表明,催化剂的适宜制备条件是WO350%、500℃焙烧2.0 h。催化合成正丁酸己酯的适宜反应条件为:n(正己醇)∶n(正丁酸)=2.0,催化剂用量2.0 g,环己烷10 mL,反应时间90 m in。在此条件下,酯化率为98.8%,催化剂使用5次后,酯化率仍可达87.6%。  相似文献   

5.
姜波张新利  赵立芳 《辽宁化工》2003,32(10):426-427,452
制备了以陶土为载体的TiO2/SO4^2-固体超强酸催化剂,并考察了它对丁酸异戊酯合成反应的催化性能。通过正交试验优化了丁酸异戊酯合成条件:催化剂活化温度600℃,催化剂用量12%(以0.15mol正丁酸为基准),反应物醇酸摩尔比1.2:1,反应时间1h,酯化率达95.2%。  相似文献   

6.
分子筛催化合成正丁酸乙酯的研究   总被引:3,自引:0,他引:3  
彭荣  李淑琴 《天津化工》2007,21(1):26-28
分子筛催化剂作为一种化工新材料在近年来得到了快速发展和广泛应用。正丁酸乙酯是一种重要的香料和用途较广泛的化工产品,本实验用硫酸特殊处理过的人造沸石作催化剂,合成了正丁酸乙酯。同时考察了合成条件对正丁酸和无水乙醇酯化反应的影响。适宜的条件为催化剂用量2g,n(正丁酸):n(无水乙醇)=1:1,5,带水剂环己烷用量为10mL,反应温度为75℃~80℃,反应时间为3h。在此条件下正丁酸的转化率在80%以上。该催化剂可以重复使用。  相似文献   

7.
对甲苯磺酸铜催化合成丁酸异戊酯   总被引:6,自引:0,他引:6  
吴长增  宋晓平 《化学试剂》2005,27(11):691-692
研究了由对甲苯磺酸与氧化铜反应制得的对甲苯磺酸铜作为催化剂,合成丁酸异戊酯,其最佳反应条件为:醇酸物质的量比1.4:1.0,反应时间1.5h,催化剂用量0.2%(以丁酸的物质的量计),反应温度120~140℃,酯化率达到99%以上。对甲苯磺酸铜制备容易,使用后处理简单,可以重复使用。  相似文献   

8.
以对甲苯磺酸为催化剂,正丁酸与异戊醇为原料合成了丁酸异戊酯,讨论了醇酸物质的量比、催化剂用量、反应时间、带水剂等因素对酯化率的影响,确定了最佳工艺条件为:以0.2mol正丁酸为基准,醇酸物质的量比为1.5:1,催化剂用量为0.5g,反应时间为2h,带水剂环己烷为7.5mL,丁酸异戊酯的酯化率为95.8%。该催化剂具有催化活性高,使用量少,酯化率高,与目前工业中使用的硫酸相比,环境污染小,对设备几乎无腐蚀等优点,且对甲苯磺酸价格低廉易得,性质稳定,使用方便,是一种很有发展前景的催化剂。  相似文献   

9.
氨磺酸催化合成丁酸异戊酯的研究   总被引:6,自引:0,他引:6  
赵汝琪 《化工科技》2000,8(5):30-32
以氨磺酸为催化剂催化合成了丁酸异戊酯,确定了酯化优化条件。实验结果表明,醇酸摩尔比值为1.8;催化剂用量1.0g;带水剂甲苯15ml(丁酸用量为0.2mol的情况下);反应温度为110-135℃;反应时间2.0h;是最佳反应条件,酯化率98.5%。  相似文献   

10.
采用聚氧乙烯醚,通过酯化反应合成高沸点、化学性质稳定的分散剂。实验选用聚氧乙烯醚和丁酸,系统地研究了不同的物质的量的比例、温度、催化剂含量和反应时间对酯化反应的影响。研究表明:当醇与酸物质的量的比为1:1.2,反应温度为120℃,催化剂含量为聚氧乙烯醚质量的0.1%,反应时间为5h,得到的酯化率为85%。  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   

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17.
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   

18.
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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