原位高效利用湿法磷酸中Mn2+的工艺研究

在湿法磷酸生产水溶磷酸一铵的过程中,通过向中和阶段添加螯合剂乙二胺四乙酸二钠(EDTA-2Na),直接生产出含Mn~(2+)的水溶肥,既满足了农作物生长需求,又实现了湿法磷酸中Mn~(2+)的原位高效利用。考察螯合温度、螯合剂添加量和螯合pH对螯合效率的影响。结果表明,在反应温度为30℃,螯合剂添加量为湿法磷酸质量的0.5%,螯合pH为3的条件下,Mn~(2+)的螯合率最高为11.0%。并通过对产品的FT-IR分析,证明了螯合机制为配位反应。     

绿色螯合剂亚氨基二琥珀酸的合成及螯合性能

亚氨基二琥珀酸是一种新型的氨基多羧酸螯合剂,有着很强的螯合过渡金属离子的能力,并具有良好的降解性,被称为绿色化学品。本文研究了用顺丁烯二酸酐(MA)、氢氧化钠、氨在水溶液中合成亚氨基二琥珀酸的工艺和反应机理,考虑了温度、原料配比和反应时间等对产品收率的影响,研究了亚氨基二琥珀酸的螯合性能,并与经典的螯合剂EDTA做了比较。结果表明,合成反应较合适的原料摩尔比n(MA)∶n(NaOH)∶n(NH3)∶n(H2O)=2∶3∶2∶16,较好反应温度160℃,反应时间10.0 h。在该反应条件下,亚氨基二琥珀酸的收率大于80.0%;反应很可能是顺丁烯二酸与氨生成天门冬氨酸,天门冬氨酸再与顺丁烯二酸反应生成亚氨基二琥珀酸;亚氨基二琥珀酸对大多数金属的螯合能力接近EDTA的水平,有些甚至超过EDTA。     

GLDA螯合态重金属在某农田下包气带土层中的吸附特性

本试验选择典型可降解螯合剂GLDA,并与不可降解螯合剂EDTA形成的螯合态重金属(Pb、Cd)进行某农田下包气带土层的吸附实验,为评估螯合强化植物提取土壤修复所形成的螯合态重金属下渗迁移带来的地下水污染风险提供评价依据。结果为:螯合态重金属(Pb、Cd)的吸附量显著低于空白对照组,吸附量大小表现为CKGLDAEDTA,且螯合态Pb的吸附量大于Cd,表明螯合强化植物提取将加剧螯合态重金属的渗漏,且EDTA螯合态重金属的渗漏风险大于GLDA。     

水溶性螯合剂在重金属废水处理中的应用

一、概述水溶性螯合剂是一种链状螫合聚合物,它可分为低分子螯合剂和高分子螯合剂。低分子螯合剂有乙二胺四乙酸钠(EDTA)、二乙基二硫代氨基甲酸钠(DDTC)、乙基黄原酸钠、1,2-二巯基丙醇、8-羟基喹啉、二     

乙二胺四乙酸螯合铁钠微肥的合成

以乙二胺四乙酸钠(EDTA-2Na)和硫酸铁为原料,在常压下通过螯合反应成功地合成了乙二胺四乙酸铁钠(C_(10)H_(12)FeN_2NaO_8·3H_2O)有机微肥。通过单因素法,改变螯合过程中原料配比、温度、时间、溶液pH值等因素,优化乙二胺四乙酸铁钠螯合微肥的制备工艺条件。实验表明,当螯合的原料EDTA-2Na和铁离子的摩尔配比为1:0.9、温度为80℃、溶液pH值为5.5、反应时间为3h时,合成样品的指标达到最佳,铁离子螯合率为98%,螯合铁元素的质量分数为13.3%。     

湿法磷酸中锰离子的高值化利用研究

以SCU-Ⅱ作为螯合剂在中和工段对湿法磷酸中的锰元素进行原位螯合,一步生产出含锰元素的磷酸一铵肥料,实现对湿法磷酸中锰离子的高效利用。考察反应时间、反应温度、螯合p H值及螯合剂的添加量对螯合效果的影响。结果表明,较优的实验条件为反应时间60 min、反应温度50℃、最佳螯合p H值为3、螯合剂的相对添加量为1.5%,此时锰离子螯合率为37.51%。     

绿色螯合剂谷氨酸二乙酸四钠和N,N-二羧甲基丙氨酸三钠盐的相对安全性与其应用

本文回顾三聚磷酸钠在洗涤剂的应用以及现今全球禁磷的法规状况。另外也讨论了传统螯合剂如NTA与EDTA的最新危害标示,以及绿色螯合剂GLDA(谷氨酸二乙酸四钠)与MGDA(N,N-二羧甲基丙氨酸三钠盐)的相对安全性质与应用特性。最后分享了绿色螯合剂在三个洗涤剂应用的例子。     

一种微量元素螯合铜盐的制备研究

利用乙二胺四乙酸和乙二胺四乙酸二钠对微量元素铜进行了螯合试验,试验结果表明,最佳螯合条件为:温度80~100℃,反应时间1~1.5 h,螯合剂与Cu2+摩尔比为1∶1,该条件下螯合率达98%以上,螯合物在180℃时性状稳定。此外,定性实验结果表明反应液中不存在游离态的Cu2+,说明螯合剂与Cu2+完全螯合。确立了最佳工艺和制备技术,并讨论了温度、螯合比等条件对螯合反应的影响。     

电感耦合等离子体发射光谱仪测定水溶肥中EDTA螯合态钙

水溶肥中的中量元素钙为了保证其在肥料中的稳定性和作物吸收上的高效性部分存在于EDTA的螯合态下,这部分钙不能采用EDTA滴定法测定,实验室主要检测方法为高锰酸钾滴定法,较为繁琐,也不能直接采用ICP-OES法直接测定,因为酸性环境会导致固体析出,堵塞毛细管,利用本文中提出的酸解后,再加入10mL EDTA进行充分螯合,及时调整p H值到9.0～10.0之间,碱性环境下,钙在EDTA螯合下不会形成沉淀,经测定相对标准偏差小于2%,加标回收率在98.5%～102.25%之间,ICP-OES测定的结果和高锰酸钾滴定法基本一致。表明这种简单的处理方法对ICP-OES快速测定水溶肥中EDTA螯合态钙准确、有效。     

高分子螯合剂的合成及性能研究

以淀粉为原料,用其接枝丙烯酸甲酯,然后与二乙烯三胺反应,合成具有多个酰胺基和胺基的螯合淀粉(SMAEN)。将其用于螯合铜离子的实验,用原子吸收光谱仪测定螯合前后金属离子溶液的浓度,并讨论了金属离子溶液的pH值、螯合时间、螯合剂加入量对螯合量的影响。实验测得该螯合剂对铜离子的最大螯合量为2.69mmol/g,证明了此螯合剂具有较好的螯合能力。     

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。