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1.
苯甲酸液相催化氧化合成苯酚   总被引:1,自引:0,他引:1  
研究了苯甲酸液相空气催化氧化合成苯酚在2 L不锈钢反应器中进行的反应,考察了反应规律.通过单因子实验得最佳工艺条件为 反应温度230 ℃,空气流量4.5 l/min,搅拌转速600 r/min,催化剂质量分数4%(Cu) ,助催化剂质量分数2%(MA).通过均匀实验设计,建立了苯酚产率与相关实验条件在实验条件范围内的回归方程Y=47.15-0.915X1-0.57X2+2.895X3;重复实验收率达到80 %(摩尔分数).苯酚选择性达到90%(摩尔分数)以上,达到了工业化中试应用的要求.  相似文献   

2.
采用分子筛法对提高异丙苯法合成的苯酚产品的质量进行了研究,探讨了使苯酚硫酸着色率(UVT)值达到指标要求(≥90%)的工艺条件。通过对苯酚原料的GC-MS分析和对原料与产品的UVT及总酮量分析,定性地说明了影响UVT值达标的主要杂质为沸点高于苯酚的酮类化合物。以Y型分子筛为催化剂研究了反应温度、反应时间及催化剂用量等因素对提高苯酚UVT值的影响。实验结果表明,在反应温度120-170℃、反应时间0.25-1.0h、反应催化剂用量为原料苯酚质量的0.25%-2.0%条件下,反应产物经适当减压精馏可得到UVT达到95%以上的高纯度酚。  相似文献   

3.
在自行建立的管式反应器上,采用实验室开发的NY-2催化剂,以环氧乙烷(EO)吸收溶液和CO2为原料,进行合成碳酸乙烯酯(EC)连续过程研究.考察液空速、吸收溶液中EC与乙二醇(EG)摩尔比、EC与EO摩尔比、水含量、催化剂用量、反应压力和温度对反应的影响.通过实验研究,确定了较佳的连续反应条件:反应温度为(125±5)℃、反应压力为(3.5±0.5)MPa、催化剂质量分数不小于2%、吸收溶液中水的质量分数少于1.2%、EC与EO摩尔比为5、EG质量分数小于30%、空速小于0.67h^-1。在此条件下,EO的转化率大于98%,EC的选择性大于80%.  相似文献   

4.
顾振鹏  王勇  张晓娜 《辽宁化工》2013,(11):1274-1275,1283
通过相转移催化法合成苯甲醚新工艺,苯酚钠与一氯甲烷在相转移催化剂催化下合成了苯甲醚。最佳的反应条件为:苯酚与氢氧化钠摩尔比为1:1~2,苯酚与-氯甲烷摩尔为1:1.2~3,反应温度70~80℃,压力1.0~2.0MPa,反应时间4~8h,相转移催化剂的用量为苯酚重量的0.01%,苯甲醚的收率可达95%以上。  相似文献   

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在超声辅助条件下,采用自制的CI催化剂,对碳酸二甲醣与苯酚酯交换法反应合成碳酸二苯酯进行研究,寻找最佳的反应条件。实验结果表明反应在超声功率为55%、175℃下,碳酸二甲酯与苯酚的摩尔比为0.85:1,碳酸二甲酯滴加速率为:1.5mL/min,催化剂添加最3%,反应时间为12h,碳酸二苯酯的产率可以达到56.78%.通过红外光谱分析确定了所制备的产物即为碳酸二苯酯,气相色谱分析确定产品的含量为99.53%。  相似文献   

6.
以邻甲苯胺为原料,采用重氮化-水解法制备高纯度邻甲酚,通过正交实验和单因素实验对重氮化反应工艺条件进行了优化。实验结果表明,该反应的优化条件为:重氮化n(硫酸):n(邻甲苯胺)=3.4:1.0,硫酸溶液质量分数为3%,亚硝酸钠溶液的质量分数为35%,加料速度为0.8mL/min,重氮液的滴加速度为20mL/min。此优化条件下,邻甲酚收率可达86.2%,纯度99.5%。  相似文献   

7.
研究了微波辐射作用下同体超强酸TiO2/SO^2-4催化葵花籽油与甲醇通过酯交换反应制备生物柴油,考察了催化剂用量、反应时间、微波功率和醇油摩尔比对酯交换反应的影响。实验结果表明,当醇油摩尔比为12:1、催化剂用量(催化剂与油的质量比)为2%、微波功率为300W、反应时间为25min时,生物柴油的收率可以达到94.3%。  相似文献   

8.
以磺化改性石油沥青作为一种新型、廉价高效且对环境友好的固体酸催化剂,催化苯酚与叔丁醇的烷基化反应。考察了其催化活性,并系统的研究了酚醇摩尔比、催化剂用量、反应温度、反应时间诸因素对苯酚转化率、产品选择性和催化剂重复使用性的影响。确定了最佳反应条件为T=70℃,t=360 min,n(TBA)/n(Phen01)=2:1,催化剂用量为0.6g,在此条件下,苯酚的转化率达到75.8%。  相似文献   

9.
樊真  江国顺 《安徽化工》2001,27(5):31-34
以2,4-二溴苯酚和POCl3在催化剂存在下合成多功能助剂BPP的方法及其应用,详细地研究了各种工艺参数对合成BPP的影响。结果表明:适宜的反应条件是2,4-二溴苯酚和POCl3的摩尔比为3.0-3.1:1,催化剂A用量为2,4-二溴苯酚重量的1.0%-1.5%,反应温度80-140℃,反应时间6-8h,BPP收率≥80%,应用研究表明:BPP阻燃性能和加工性能好,能改善材料的机械性能,对材料的透光性无影响,而且BPP还兼有避鼠和防霉性能。  相似文献   

10.
程丽华  汪树清 《辽宁化工》2006,35(7):382-384,400
以甲基叔丁基醚(MTBE)为烷基化试剂,通过正交实验研究了苯酚叔丁基化合成2,4-二叔丁基苯酚的反应规律,分别考察了一步法和两步法合成工艺的规律,结果表明:利用一步法,目标产物收率较高,在n(苯酚):n(MTBE)=1:2.1、反应时间60min、催化剂(浓硫酸)用量1.0mL、反应温度85℃时,目标产物的收率可达61.5%。  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   

12.
It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.  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   

18.
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   

19.
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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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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