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1.
阳离子交换树脂催化合成阿魏酸乙酯   总被引:1,自引:0,他引:1  
以乙醇和阿魏酸为原料,强酸性阳离子交换树脂为催化剂,直接酯化合成了阿魏酸乙酯,考察了树脂类型、催化剂用量、物质的量比、反应时间、催化剂重复使用性等因素对反应的影响。确定了最佳反应条件为:m(树脂)/m(阿魏酸)=0.12,n(乙醇)∶n(阿魏酸)=6∶1,加热回流反应7 h。在最佳反应条件下,阿魏酸转化率为83.4%,产品收率为78.1%。732型树脂催化剂重复使用4次,阿魏酸转化率不低于81%,收率不低于75%。  相似文献   

2.
新型催化剂一步法合成防腐防霉剂富马酸二甲酯   总被引:3,自引:0,他引:3  
以强酸性阳离子交换树脂/磷酸-硫脲为催化剂,结合甲醇精馏回流,马来酸酐为原料,一步法合成了富马酸二甲酯。优化工艺条件为:催化剂组成m(阳离子交换树脂)∶m(磷酸)∶m(硫脲)=1∶0.08~0.1∶0.21~0.25,以马来酸酐计,催化剂用量质量分数w(催化剂)=10%~12%,物料比n(马来酸酐)∶n(甲醇)=1∶5,反应温度70~75℃。所得产品含量达99%以上,主催化剂阳离子交换树脂可直接重复使用6次,再生容易。与传统工艺比较,对设备腐蚀和环境污染大大减轻,产品收率达91%以上。  相似文献   

3.
董强  梅华  陈亚飞 《精细化工》2012,29(3):258-261
以氯甲基聚苯乙烯树脂分别与三甲胺、三乙胺、三丁胺、三乙醇胺、吡啶5种叔胺反应,制备了不同的聚合物三相相转移催化剂,并用于间二硝基苯精制,考察了催化剂、氢氧化钠、甲醇的用量及催化剂种类对邻、对二硝基苯转化率的影响,得到了适宜的精制工艺条件为:m(粗间二硝基苯)∶m(甲醇)∶m(NaOH)∶m(聚苯乙烯吡啶树脂)=1∶0.8∶0.1∶0.12,反应温度76~78℃,反应时间2 h。在该条件下,邻对二硝基苯的转化率在99.5%以上,精制后的间二硝基苯经色谱分析后其色谱纯度达99.8%,间二硝基苯的收率在99%左右,聚苯乙烯吡啶树脂催化剂可重复使用7次以上。  相似文献   

4.
甲醇钠催化地沟油制备生物柴油研究   总被引:2,自引:0,他引:2  
赵华  李会鹏 《化工科技》2011,19(6):19-22
以浓硫酸为催化剂,高酸值地沟油与甲醇酯化反应降酸的最优工艺条件为:n(甲醇):n(地沟油)=9:1,m(浓硫酸):m(地沟油)=1.1%,反应温度60℃,反应时间5h.制备生物柴油的最优工艺条件为:以甲醇钠为催化剂,反应时间2h,反应温度65℃,n(甲醇):n(地沟油)=7:1,m(甲醇钠):m(地沟油)=0.8%.制...  相似文献   

5.
以新型、绿色强酸性阳离子交换树脂CT169为催化剂,葡萄糖和乙二醇为原料合成乙二醇葡糖苷。考察了催化剂用量、醇糖摩尔比和反应温度对葡萄糖转化率的影响,探讨了该反应的反应机理,并建立了反应的动力学模型,求取了模型的相关参数。结果表明,较佳反应条件为:n(乙二醇)∶n(葡萄糖)=7∶1,强酸性阳离子交换树脂CT169用量为葡萄糖物质的量的35%,反应温度为100℃,反应时间为5 h,在此条件下葡萄糖转化率达99.33%。催化剂重复使用7次,葡萄糖转化率基本不变,具有较好的重复使用性能。该过程为拟一级可逆反应,表观活化能Ea+=41.572 k J/mol,指前因子k0=7.716×103min-1。  相似文献   

6.
丁二酸催化酯化-吸附脱水联合工艺   总被引:11,自引:0,他引:11  
以阳离子交换树脂NKC-9固体酸为催化剂、丁二酸和甲醇为原料,采用分子筛吸附脱水技术合成丁二酸二甲酯. 考察了原料配比、催化剂用量和反应时间等因素对酯化反应的影响,通过实验得到了最佳酯化反应工艺条件:n甲醇/n丁二酸=3.0:1, NKC-9为3.5%(w)、反应温度≤120℃、反应时间4 h,在该条件下丁二酸的转化率达到98.86%. 催化剂重复使用6次后,丁二酸的转化率仍可达到98.09%. 利用红外光谱、色谱-质谱对产品进行分析,结果显示,产物中没有副产物,反应选择性很高.  相似文献   

7.
以H3PW12O40/聚苯胺(PANI)为催化剂,柠檬酸和异辛醇为原料合成柠檬酸三辛酯。考察了n(异辛醇)∶n(柠檬酸)、催化剂用量、反应时间等因素对反应转化率的影响,以及催化剂的重复使用性能,并测定了动力学数据。确定了较佳反应条件为n(异辛醇)∶n(柠檬酸)=5∶1、m(H_3PW_(12)O_(40)/PANI)∶m(醇酸)=4%、反应温度≤140℃、反应时间4h。较佳反应条件下柠檬酸的转化率为96.6%;催化剂重复使用4次,柠檬酸的转化率为64.1%,反应总级数为二级,表观活化能为39.42kJ/mol,指前因子为1.972×10~2 L/(mol·min)。  相似文献   

8.
对甲苯磺酸掺杂聚苯胺催化合成乳酸正丁酯   总被引:3,自引:0,他引:3  
以乳酸和正丁醇为原料催化合成乳酸正丁酯,考察了原料配比、PTSA/PANI(是用对甲苯磺酸作为掺杂剂采用苯胺直接水相氧化法制备由聚苯胺(PANI)负载对甲苯磺酸的固体酸催化剂)用量、反应时间以及催化剂的重复使用等对反应的影响.确定较佳反应条件为:n(正丁醇):n(乳酸)=2.0:1、w(PTSA/PANI)=3.0%、反应温度≤130℃、反应时间3 h.结果表明,在该条件下乳酸的转化率为96.4%;催化剂经重复使用5次后,乳酸的转化率为91.8%.  相似文献   

9.
聚苯乙烯-二乙烯苯接枝聚乙二醇催化合成对硝基苯甲醚   总被引:2,自引:0,他引:2  
探素了诸因素对制备催化剂过程的影响,合成出了聚苯乙烯-二乙烯苯接枝PEG-400并以此为三相转移催化剂。研究了对硝基苯甲醚的合成工艺,考察了催化剂,氢氧化钠、甲醇用量等对反应转化率的影响,建立了较佳合成工艺条件,即:n(PNCB):n(CH3OH):n(NaOH):n(PEG-400)=1:3:3:0.03-0.05,反应温度-80℃,反应时间9-10h。该条件下,对硝基氯苯转化率>99.5%,以对硝基氯苯计,对硝基苯甲醚收率>95%,气相色谱分析产品纯度99.7%。聚苯乙烯-二乙烯苯接枝PEG-400催化剂可重复使用5次以上,母液除盐后用于配碱对反应无不良影响。  相似文献   

10.
《应用化工》2016,(6):1107-1110
以大孔强酸性阳离子交换树脂为催化剂,以葡萄糖和乙二醇为原料合成了乙二醇葡萄糖苷。探讨了催化剂用量、醇糖摩尔比和反应温度对反应的影响,得到最优的反应条件为:n(乙二醇)∶n(葡萄糖)=7∶1,n(催化剂)∶n(葡萄糖)=0.25∶1,反应温度为100℃,产品收率可达90.58%,催化剂重复使用5次,产品收率基本不变,具有较好的回用性能。对乙二醇葡萄糖苷的保湿性能进行了研究,发现乙二醇葡萄糖苷的保湿性优良,可用于日化保湿剂行业中。  相似文献   

11.
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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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   

16.
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   

17.
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   

18.
Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

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Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.  相似文献   

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