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1.
针对含0.015~0.03 g?mL~(-1)的N-羟基丁二酰亚胺(HOSU)水溶液,采用三辛胺(TOA)、正丁醇组成萃取剂,在单级液液萃取装置中通过实验筛选出最优萃取体系,考察了TOA的体积分数、两相相比、萃取温度、盐析剂等对HOSU在油水两相中分配系数的影响,并测定了该系统在25℃下的相平衡数据。红外光谱图分析结果表明TOA对HOSU的络合萃取同时存在氢键缔合和离子缔合两种形式。基于质量作用定律,建立了表达该萃取过程的相平衡模型,对25℃的萃取相平衡数据进行关联,结果表明有机相中HOSU浓度的实验值与模型计算值吻合良好。  相似文献   

2.
三辛胺萃取草酸的第3相特性   总被引:1,自引:0,他引:1  
曹雁青  秦炜  戴猷元 《化工学报》2003,54(5):585-589
以三辛胺(TOA)萃取草酸时出现第3相的基本规律为研究对象,实验测定了无水溶剂及液液萃取平衡有机相中草酸的溶解度及其随TOA和正辛醇浓度的变化规律.结果显示,正辛醇对草酸及其与TOA形成的缔合物在溶剂中的溶解度影响显著;随正辛醇含量的增加,草酸及其缔合物在溶剂中的溶解度提高,因而溶剂对草酸的萃取能力随之增大;在TOA与草酸以1∶1的化学计量比饱和后,草酸溶解度出现阶跃现象,这与形成草酸二聚体的缔合物有关;相比之下,液液萃取平衡实验中有机相对草酸的溶解度大于无水溶剂的结果,溶剂中水的存在有助于缔合物溶解.同时建立了描述液液萃取平衡有机相中草酸及其缔合物溶解度的数学模型,并通过参数寻优求得了相应的模型参数.  相似文献   

3.
本文提出了多元缔合体系汽-液相平衡的热力学模型,并用其计算了缔合体系水-甲酸-乙酸、水-乙酸-丙酸、水-甲酸-丙酸及甲酸-乙酸-丙酸在760mmHg下的实验液相活度系数。活度系数的计算值由Wilson方程或McCann方程给出。由相应二元体系的汽-液相平衡数据对三元体系的沸点及汽相组成进行了预测。结果表明,预测值能较好地同实验数据相吻合。  相似文献   

4.
采用三正辛胺(TOA)作为络合剂,异辛醇和煤油分别作为助溶剂和稀释剂,对生物油中的乙酸进行了络合萃取研究。考察了TOA体积分数、异辛醇浓度、萃取剂与生物油轻馏分体积比以及温度对乙酸萃取率的影响,结果表明:温度为0 ℃,萃取体系为40%TOA+40%异辛醇+20%煤油(各组分浓度均为体积分数,下同),萃取剂与生物油轻馏分体积比为3∶1时,乙酸的一次萃取率较高,可达74.6%。  相似文献   

5.
液液相平衡数据是化工萃取过程设计和模拟计算的基础,为了给以甲基戊烯酮为溶剂的含酚废水萃取过程设计和流程模拟计算提供基础数据,本实验采用平衡法分别测定了25、40和50℃常压下甲基戊烯酮-水-苯酚三元物系液液相平衡数据,并绘出了各温度下的分配系数曲线。同时,采用NRTL活度系数模型对实验数据进行了关联,回归得到了该三元物系的二元交互参数。运用回归得到的模型参数,对该三元物系的相平衡数据进行计算,结果表明该模型可以很好地关联实验数据,模型计算值与实验值的相对均方根误差和绝对平均误差均在1.5%以内。  相似文献   

6.
缔合体系汽-液平衡的研究(Ⅰ)——二元缔合体系   总被引:1,自引:0,他引:1  
本文给出了含缔合组分二元体系汽-液相平衡的热力学模型,本模型假定相同缔合分子间发生二分子、三分子及四分子缔合;不同缔合分子间发生二分子缔合;并考虑了汽相的非理想气体行为。用其计算了二元体系甲酸-水、乙酸-水、丙酸-水、甲酸-乙酸、乙酸-丙酸及甲酸-丙酸的液相活度系数的实验值,其计算值由Wilson方程或McCann方程给出。结果表明,本热力学模型对上述体系是适用的。  相似文献   

7.
二元交互作用参数是萃取分离过程模拟和设计的关键数据,它通常是通过液液相平衡测定的数据回归得到。在常压下测定了25℃时甲基叔丁基醚-丙酸-丁酸-水四元体系液液相平衡数据,用NRTL和UNIQUAC模型对所测实验数据进行热力学关联,采用Bachman、Othmer-Tobias和Hand公式验证了数据的可靠性状况,利用模拟软件回归得到二元交互作用参数。结果表明,基于NRTL和UNIQUAC模型关联计算得到的计算值与实验值吻合良好,两种模型计算的相对均方根偏差分别小于0.0122和0.0184,说明两个模型回归得到的二元交互作用参数均能对实验液液相平衡数据进行很精确地预测。  相似文献   

8.
为了给以甲基异丁基酮为溶剂的含酚废水萃取过程设计和流程模拟计算提供基础数据,实验测定了常压,25、40和50℃下甲基异丁基酮-水-苯酚三元物系在稀酚水范围内的液液相平衡数据。采用NRTL活度系数模型对实验数据进行了关联,回归得到了该三元物系的二元交互参数。运用回归得到的模型参数,对该三元物系的相平衡数据进行预测计算,结果表明该模型可以很好地关联实验数据,模型计算值与实验值的相对均方根误差和绝对平均误差均在2%以内。  相似文献   

9.
滕尧  齐鸣斋 《上海化工》2014,39(10):4-6
在甲基三丁酮肟基硅烷的生产过程中会产生部分含丁酮肟的废水,用萃取方法可回收丁酮肟。为获得萃取工艺所需的基础数据,在常压、60℃温度下,以工业实际废水为物料,进行液液相平衡实验,用拟三元方法处理丁酮肟-水-异辛醇三元体系的液液相平衡数据,获得了三元体系平衡相图。实验数据用非随机两相液体(NRTL)模型进行了关联,得出了该三元体系的NRTL模型参数。将实验数据与关联结果进行比较,结果表明,NRTL模型能对该三元体系进行较准确的关联。  相似文献   

10.
测定了水-仲丁醇-乙酸仲丁酯三元体系在303.15,323.15,343.15,353.15 K下的液液相平衡数据,并用NRTL模型和UNIQUAC模型对相平衡数据进行关联,应用单纯形法求得相应的模型参数。计算值与实验值比较结果表明:NRTL模型与UNIQUAC模型的计算值与实验数据吻合良好。  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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