饲钙厂磷酸萃取装置的工艺改进

针对饲料级磷酸氢钙生产的特点,提出了对与之相配套的磷酸萃取装置的改进:在原萃取磷酸工艺中增加预反应过程和分离过程,磷矿粉(浆)先加入预反应器中,与过滤后的所有滤酸混合,以使矿中部分CaO溶于磷酸生成磷酸二氢钙;经分离,将未分解的大部分磷矿送萃取系统制磷酸,溶液脱氟、除杂后用于制备磷酸氢钙以节约酸耗与石灰消耗。技改后,改善了石膏结晶状况,过滤强度由350～400kg(干基)/(m2·h)提高到500～650kg(干基)/(m2·h);还可用MgO偏高的低质磷矿。     

饲料级脱氟磷酸三钙制备的研究

以四川磷矿为原料,在高温焙烧炉中采用磷酸法高温烧结工艺,较为系统地研究了焙烧时间、焙烧温度、磷酸配比和反应器对磷矿分解和脱氟反应的影响。结果表明：焙烧时间、焙烧温度、磷酸配比和反应器的传质特性对磷矿分解和脱氟反应均有显著影响。在改进型反应器中,焙烧时间≥90min、焙烧温度1180～1230℃、磷酸配比24％～27％、磷酸质量分数45％,产品中P205质量分数可达41．0％～42．5％,而F质量分数≤0．16％。     

提高磷酸二铵产品中总氮含量的研究

对影响磷酸二铵总氮质量的因素进行了分析,通过缩小萃取磷酸SO3控制范围、延长磷酸陈化和澄清时间、降低澄清酸含固量和杂质含量、优化磷矿浆浓密系统、提高磷矿浆浓度、调整预中和反应器和管式反应器中的氨化(中和)比例、降低DAP产品中水分等措施,解决了磷矿品位下降,杂质含量升高所带来的DAP总氮含量难以达标的问题。     

工业磷酸分解磷矿影响因素及副产物性质研究

为改进湿法磷酸生产工艺,提高副产磷石膏的品质,减少湿法磷酸固体副产物堆存产生的经济和环境压力,进行了工业磷酸分解磷矿制磷酸的实验,同时对固体副产物的性质进行了分析。工业磷酸分解磷矿制磷酸的工艺分为两步：第一步,工业磷酸与磷矿反应,得到磷酸二氢钙溶液和酸不溶渣;第二步,浓硫酸与磷酸二氢钙溶液反应,得到磷酸溶液和高纯石膏。采用单因素实验考察了酸比（工业磷酸用量与理论磷酸用量的物质的量的比值）、磷矿粒度、反应温度和反应时间对磷矿中磷浸出率的影响。得到磷矿酸解适宜工艺条件：酸比为6.8,磨矿细度为小于0.074 mm粒级占60%,反应温度为50 ℃,反应时间为2.5 h。在此条件下,磷矿中磷的浸出率可达87.69%。磷矿酸解制磷酸产生的固体副产物中石膏占35.32%（质量分数）、酸不溶渣占64.68%（质量分数）。制备的高纯石膏的纯度为95.80%,工业利用价值较高,有利于提高湿法磷酸固体副产物的利用率。     

磷酸分解磷矿的微化工工艺研究

采用传统反应器磷酸分解磷矿时,磷矿分解不够充分,反应时间较长,容易造成资源浪费.微反应器具有反应空间小、传质效果好以及反应时间短等优势.采用T型微通道反应器进行磷酸分解磷矿研究,最佳条件为:反应时间30 min,m(磷酸)/m(磷矿)为8,反应温度70℃,磷矿粒径<0.080 mm,磷酸质量分数30％.在最佳条件下,磷...     

工业磷酸组分对磷矿浸出的影响研究

用工业磷酸分解磷矿制磷酸,其组分会对酸解磷矿效果产生影响,为此通过用工业磷酸与纯磷酸进行磷矿浸出对比试验,结合在纯磷酸中添加H_2SO_4、MgSO_4、Al_2(SO_4)_3和Fe_2(SO_4)_3进行磷矿浸出试验,考查了H+、PO43-、SO42-、Mg~(2+)、Al ~(3+)和Fe~(3+)对磷酸分解磷矿性能的影响。试验表明,在相同PO43-浓度下,用纯磷酸浸出磷矿的效果明显优于工业磷酸,说明PO43-浓度不是影响磷矿浸出效果的主要因素。在纯磷酸中加入H_2SO_4可明显改善磷矿浸出效果,而加入MgSO_4、Al_2(SO_4)_3和Fe_2(SO_4)_3对磷矿浸出效果的影响不明显,说明SO42-、Al~(3+)、Mg~(2+)、Fe~(3+)对浸出效果影响不大,真正影响磷矿浸出效果的因素是H+浓度。     

九字沟磷精矿制湿法磷酸模型试验

<正> 湿法磷酸是制备高效复合(混合)肥料的重要中间产品。为了开发以陕西磷矿为原料制湿法磷酸的生产技术,加速西北地区磷肥工业的发展,我们以九字沟磷精矿为原料,进行了二水物法萃取磷酸工艺条件试验。一、工艺过程及基本原理在湿法磷酸生产过程中,磷矿的分解     

磷酸分解磷矿化学反应过程研究

为提高用中低品位磷矿制得湿法磷酸的浓度 ,实验用ω(P2 O5)≈ 2 0 %、较洁净的磷酸 ,与云南上蒜磷矿进行分解反应。在实验条件下 ,研究了分解产物Ca(H2 PO4 ) 2 在磷矿颗粒表面形成固体膜的特性 ,以及磷矿粒度、反应时间、反应温度和磷酸初始浓度对磷矿分解率的影响。用扫描电镜观察了磷矿颗粒表面形成的固体膜的形貌特征 ;用粒径不变的缩芯模型来描述磷酸分解磷矿的过程 ;用所测实验数据回归得到了磷酸分解磷矿的经验模型     

尼日利亚某中品位磷矿二水法制磷酸实验研究

磷矿湿法加工制取磷酸新装置建设需要根据磷矿性质（化学组成、物相等）的不同进行独立设计,通过在实验室模拟湿法磷酸工业化流程（反应、结晶、过滤）,得到特定磷矿下的制酸工艺参数,可以减少工业化装置试验成本。根据业主委托,采用传统二水法磷矿制酸工艺对尼日利亚某中品位磷矿进行了实验室制酸模拟实验,利用单因素法研究了湿法磷酸工艺主要控制参数包括游离三氧化硫浓度、磷酸浓度、停留时间、温度和料浆液固比对磷矿制酸工艺的影响,得到最适宜的工艺条件：游离三氧化硫质量浓度为25~30 g/L,磷酸纯度（以五氧化二磷质量分数计）为22%~23%,停留时间为4 h,反应温度为75~78 ℃,料浆液固质量比为2.5∶1。在上述条件下,磷矿中五氧化二磷转化率≥93%,五氧化二磷回收率约为90%,料浆的过滤强度（以五氧化二磷计）为8.1 t/（d·m²）。后期跟踪发现,实验室制酸模拟装置得到的实验结果与后期工业化试验结果基本一致。     

硫酸分解织金含稀土磷矿化学反应过程实验研究

根据湿法制磷酸工艺,采用工业硫酸分解织金含稀土磷矿,研究了反应温度、磷矿粒度和硫酸浓度对贵州织金含稀土磷矿分解率的影响。反应温度为338~348 K,磷矿粒度为0.110~0.075 mm和硫酸的浓度为22.0%~25.0%的条件下,用粒径不变的缩芯模型来描述工业硫酸分解织金含稀土磷矿化学反应过程。推导出了该过程的理论模型和实验数据的回归模型,方差分析表明模型可靠。为工艺条件的优化和反应器的设计提供了理论依据。     

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。