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1.
研究了在乙醇作为添加剂的三乙醇胺反应介质中,以磷石膏和氯化钾为原料制取硫酸钾的新工艺。得出的优化工艺条件为:磷石膏过量10%,液固比2∶1,反应温度20℃,三乙醇胺质量分数75%,反应时间2h,先加氯化钾与反应溶剂,磷石膏分两次加入。在此条件下,氯化钾转化率为83.62%,硫酸钾产品的K2O质量分数为51.03%,氯离子质量分数为0.96%,水的质量分数为1.88%,产品质量达到国家标准。  相似文献   

2.
在氨介质中石膏转化法制备硫酸钾工艺研究   总被引:1,自引:1,他引:0  
崔益顺 《无机盐工业》2007,39(11):15-18
采用正交实验,研究在氨介质中,以异丙醇作为添加剂,石膏与氯化钾一步转化制取硫酸钾。采用统计分析得出其最佳工艺条件是:氨的初始质量分数26%,异丙醇的质量分数7%,反应温度20℃,反应时间60 min,液固比5.5 mL/g,原料配比(石膏与氯化钾物质的量比)1.1,结晶温度50℃,结晶时间40 min,搅拌转速350 r/min。在此条件下产品硫酸钾的最高产率可达96.64%。该法具有工艺简单、原料便宜易得、反应液腐蚀性小、产物产率高等优点,具有广阔的开发前景。  相似文献   

3.
乙醇-氨水介质中硫酸钾制备工艺研究   总被引:1,自引:0,他引:1  
以氯化钾和磷石膏为原料,采用一步法制备硫酸钾。采用乙醇-氨水为介质,通过正交实验讨论了反应时间、反应温度、乙醇质量分数、氨水质量分数、配料比对产品质量、原料转化率以及产品晶形的影响,得出优化工艺条件为:反应时间60 min、反应温度45℃、乙醇质量分数30%、氨水质量分数20%、配料比(磷石膏与氯化钾质量比)1.29∶1。在该条件下,制得产品硫酸钾的氧化钾质量分数为37.34%,氧化钾的转化率为75.56%,氯离子质量分数为0.86%,水质量分数为1.06%。  相似文献   

4.
以氯化钾和硫酸铵为原料,以甲醇为添加溶剂制备硫酸钾.通过正交实验讨论了反应时间、反应温度、甲醇质量分数、硫酸铵初始质量分数、硫酸铵与氯化钾物质的量比(配料比)等工艺参数对产品质量和氧化钾转化率的影响.得出优化工艺条件:反应时间60 min,反应温度35℃,甲醇质量分数50%,硫酸铵初始质量分数32%.配料比0.56.在该条件下氧化钾转化率达90.94%,产品氧化钾质量分数达51.95%,硫酸钾产品达到GB 20406-2006国家标准农用优等品标准.甲醇溶剂工艺与水盐体系相比较,具有过程简单、氧化钾转化率高和产品质量好等优点.  相似文献   

5.
孙志刚 《广州化工》2014,(10):106-108
以氯化亚砜(TC)、三乙醇胺(TEA)为反应原料,N,N-二甲基甲酰胺(DMF)作为溶剂,经分子间亲核取代反应合成三(2-氯乙基)胺盐酸盐。结论表明:反应温度为60℃、反应时间为4 h、溶剂质量分数为20%、n TC∶n TEA=3.9时,三乙醇胺的转化率达到95.71%,产品收率达91.22%。利用1H-NMR方法表征了三(2-氯乙基)胺。  相似文献   

6.
针对氨溶液中磷石膏制备硫酸钾工艺存在的问题,对氨-乙醇溶液中磷石膏直接制备硫酸钾的工艺进行了研究.反应条件为:φ(乙醇)=6%、初始ω(氨)= 25%、反应温度25℃、反应时间1.5h、液固比即[V(乙醇)+V(氨水)]∶[m(磷石膏)+m(氯化钾)]=5.0∶1(mL/g)、配料比n(CaSO4·2H2O)∶n(KC...  相似文献   

7.
对磷石膏和氯化钾制取硫酸钾溶剂法工艺进行了研究。考察了在氨水及乙醇-氨溶液体系中影响硫酸钾收率的主要因素。实验得到较优的工艺条件:乙醇质量分数为25%、氨水初始质量分数为25%、反应温度为5 ℃、反应时间为60 min、液固体积质量比为10∶1 mL/g。在此最优条件下,氧化钾收率达70%左右,所得硫酸钾产品质量达到农用一级品。该工艺流程简单,生产条件温和,溶剂经回收后循环使用,有利于经济效益的提高。  相似文献   

8.
为了解决氯化钾—硫酸铵法生产的硫酸钾产品纯度低的问题,对硫酸钾精制过程进行了研究。在理论指导下,根据正交设计试验结果,通过极差和方差分析,确定结晶温度、反应时间、配料比都显著影响硫酸钾的收率。同时得到精制过程的优化工艺条件;结晶温度40℃,反应时间90min,氯化钾与硫酸钾的配料质量比为0.15。实验结果为:硫酸钾的单次收率达到85.26%,循环总收率接近100%。  相似文献   

9.
研究了氨法脱硫副产的硫酸铵溶液直接与氯化钾进行复分解反应生成K2SO4结晶的工艺参数.离心分离K2SO4结晶,经干燥后制得合格的农用化肥硫酸钾产品.试验表明:反应时间3h、反应温度30℃、L/G为1.2,KCl与(NH4) S04质量比1.10条件下,采用硫酸铵与KCl定量配比投料能生产出硫酸钾合格品.  相似文献   

10.
以硫酸铵和氯化钾为原料制备硫酸钾 ,添加有机溶剂可降低硫酸钾在反应体系中的溶解度而快速析出。实验研究了 10余种有机溶剂在不同浓度对 K2 O收率的影响 ,其中 3种较为有效 ,并进行五因素四水平优化条件实验 ,得出适宜条件 :反应温度 2 5~ 30℃ ;反应时间 90~ 12 0 min;有机溶剂质量分数 5 0 %左右 ;硫酸铵初始质量分数2 8%~ 35 % ;原料配比 n(K2 Cl2 ) / n〔(NH4 ) 2 SO4 〕=0 .9~ 1.0 3,K2 O收率可达 90 %以上  相似文献   

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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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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   

15.
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   

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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   

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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