醇-酯复合萃取剂萃取湿法磷酸的相平衡研究

以醇-酯复合萃取剂为对象,对湿法磷酸溶剂萃取的液相平衡进行了研究,测定了复合萃取剂-磷酸体系在25、45、60、70 ℃相平衡时磷酸的分配曲线,考察了磷酸分配系数与温度、相比、磷酸初始浓度的关系。结果表明：复合萃取剂能萃取磷酸的最大质量分数不高于50%,温度和相比对分配系数的影响都不大,但水相磷酸初始浓度对分配系数影响很大。     

丙二醇甲醚-水-二氯甲烷液液相平衡的研究

为支撑过氧化氢直接氧化法制环氧丙烷(HPPO)生产废水中的丙二醇甲醚(包括丙二醇单甲醚和丙二醇异单甲醚2种同分异构体)萃取分离新工艺开发,选定二氯甲烷为萃取剂,测定了在常压下288.2 K和298.2 K时三元体系丙二醇单甲醚/丙二醇异单甲醚+水+二氯甲烷的液液相平衡数据,并由此绘制相平衡曲线。根据实验数据对分配系数和分离因子进行计算,结果表明：二氯甲烷作为萃取剂具有较好的萃取能力和较高的选择性。利用Othmer-Tobias方程和Hand方程分别进行实验数据可靠性、准确性检验,其线性相关系数的平方均大于0.99,同时分别用NRTL和UNIQUAC热力学模型进行关联,回归得到不同温度下的模型参数,且实验值和计算模拟值的均方根偏差均小于0.016,说明2种模型均可较好地描述该三元体系相平衡行为。     

环丁砜抽提重石脑油芳烃体系相平衡研究

采用液-液萃取技术脱除重石脑油中的芳烃。常压下,测定了含水量为0.02%、0.3%、0.5%及0.8%的环丁砜与重石脑油在剂油比1:1~5:1及温度为313.15、323.15、333.15、343.15、353.15 K的液-液相平衡数据,全面考察了环丁砜的芳烃抽提性能。结果表明,在环丁砜抽提体系中,轻质芳烃的分配系数与温度呈正比而与剂油比呈反比。环丁砜对轻质芳烃的选择性系数随温度升高而减小,随轻相中芳烃含量的降低而变大。但重质芳烃的分配系数和环丁砜对其选择性系数则随温度和剂油比变化不大。环丁砜含水量为0.5%时,在基本不改变其溶解性能的基础上使其选择性得到了明显改善。     

水-苯酚-碳酸二甲酯-正己烷液液相平衡的测定与关联

用绿色溶剂碳酸二甲酯（DMC）萃取苯酚废水消除二次污染问题。研究了20℃下的三元体系DMC-水-苯酚和四元体系DMC-正己烷-水-苯酚的液液萃取相平衡,用UNIFAC模型计算了DMC在液相中的活度系数。结果表明,苯酚在有机相和水相间的分配系数为常数,不随着水相苯酚浓度变化。当有机相初始DMC浓度不同时,分配系数不同,萃取溶剂相中初始DMC体积浓度由50％增加到80％时苯酚的分配系数由10增加到19左右。定义了新UNIFAC基团OCOO,用最小二乘法回归得到了OCOO与CH2、H2O、ACH、ACOH等基团间的相互作用参数。对三元和四元体系的液液相平衡进行了预测,结果表明得到的相互作用参数可以较好地对液液相平衡进行推算。     

[bmim][PF6]-DMF-水三元体系的液液相平衡测定

为得到含N,N-二甲基甲酰胺(DMF)废水中萃取回收DMF工艺所需的基础数据,用液液平衡釜常压下测定了1-丁基-3-甲基咪唑六氟磷酸盐([bmim][PF6)离子液体-DMF-H2O三元体系在283.15～323.15 K下的液液分层曲线和液液相平衡数据.在此基础上,考察了三元体系中DMF和[bmim][PF6]离子液体的含量以及温度对[bmim][PF6]的选择性系数的影响.实验结果表明,液液平衡相图中两相区面积随温度升高而减小;相同温度下,[bmim][PF6]的选择性系数随着三元体系中DMF的含量增加而减小,随着离子液体用量增加而增大;溶液组成一定时,[bmim][PF6]的选择性系数随着温度升高而减小;当DMF的含量大于10％时,温度对选择性系数影响不大;283.15 K,三元体系中DMF的质量分数为2.04％时,选择性系数可达33.62,[bmim][PF6]用于萃取分离水中的DMF可行.     

乙酸乙酯-间苯二酚-酸性盐水液液相平衡测定及关联

乙酸乙酯作为萃取剂在酸性盐水环境下萃取间苯二酚。平衡法测定了40℃、101.33 kPa时乙酸乙酯-间苯二酚-酸性盐水准三元体系的液液相平衡数据,实验结果表明间苯二酚的存在增加了乙酸乙酯和水的相互溶解度,降低了萃取效率;盐的存在则降低了乙酸乙酯在水中的溶解度,有利于间苯二酚的萃取。用NRTL模型对实验数据进行了关联,得到了乙酸乙酯-间苯二酚-酸性盐水体系的液液相平衡模型参数,关联结果与实验数据基本吻合。测定的液液相平衡数据可为间苯二酚萃取过程以及间苯二胺水解联产间苯二酚和间氨基苯酚的生产装置的工艺设计提供依据。     

中空纤维更新液膜传质性能的研究

研究了中空纤维更新液膜(HFRLM)技术的传质性能.以CuCl2水溶液-10%P204 煤油-盐酸为实验体系,研究结果表明,中空纤维更新液膜技术可以实现同级萃取-反萃,且总传质系数随料液相流速的增大而增大,在实验条件下,总传质系数受反萃相流速的影响较小.实验研究探讨了混合方式(料液与萃取剂混合和反萃剂与萃取剂混合)和体系分配系数对传质性能的影响.实验结果表明,由于相间分配系数的不同,总传质系数受混合方式的影响较大,以分配系数较大的一相与萃取相混合流经管程的方式对传质过程有利.     

丙烯酸-水-邻苯二甲酸二乙酯三元体系的液液相平衡

为考察邻苯二甲酸二乙酯在常压、不同温度(303.15、313.15、323.15 K)下对水溶液中丙烯酸的萃取效果,采用平衡釜法测量丙烯酸-水-邻苯二甲酸二乙酯三元体系的液液相平衡数据。数据结果表明：邻苯二甲酸二乙酯对丙烯酸具有较高的分配系数和选择性;使用Othmer-Tobias和Hand方程计算的线性相关性R²大于0.999,表明实验数据具有很好的热力学一致性,验证了实验测定数据的可靠性;拟合的UNIQUAC模型二元交互参数能很好地关联三元体系的实验数据,同时利用基于COSMO理论的电荷密度分布对萃取机理进行了解释。     

环己烷-乙醇-离子液体液液相平衡数据测定及关联

环己烷-乙醇是化工生产中常见的共沸体系,溶剂萃取是分离环己烷-乙醇的重要途径。在常压,303.15 K实验条件下,以[EMIM][OTF](1-乙基-3-甲基咪唑三氟甲烷磺酸盐)、[EMIM][SCN](1-乙基-3-甲基咪唑硫氰酸盐)、[EMIM][DCA](1-乙基-3-甲基咪唑双氰胺盐)3种离子液体为萃取剂,测定环己烷-乙醇的液液相平衡数据。利用分配系数和选择性评价不同离子液体的萃取性能。此外,根据Othmer-Tobias和Hand方程对相平衡实验数据进行一致性和可靠性校验。最后,采用Aspen Plus软件选择NRTL模型对相平衡数据进行关联,获得二元交互作用参数,并将其用于计算相应的相平衡组成。通过研究发现,计算值和实验值的均方根偏差小于0.02,表明NRTL模型能够准确描述三元相平衡过程。     

水-二乙氧基甲烷-乙苯/苯甲醚的液液相平衡

为了探索不同萃取剂萃取分离水-二乙氧基甲烷共沸物的能力,在大气压力下,以乙苯和苯甲醚为萃取剂,分别测定了303.15和313.15 K时水-二乙氧基甲烷-乙苯/苯甲醚体系的液液相平衡数据.通过计算所得分离因子远大于1,表明乙苯和苯甲醚均为此体系的优良萃取剂.使用Othmer-Tobias和Hand经验方程对实验数据进行...     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

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.     

2007～2008年世界塑料工业进展

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.     

2005～2006年国外塑料工业进展

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。