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1.
本文运用撞击流反应器,以工业亚硫酸铁,磷酸为原料由水热法制备电池级超细磷酸铁并探究了相关反应条件对产品粒径的影响,确定了适宜工艺条件为:制备原料液过程中氧化反应温度65℃,过氧化氢过量用量为理论量的120%,氧化时间1小时;撞击流反应器中反应条件为反应、结晶温度90℃,Fe3+浓度为0.4 mol/L,磷铁比1.4:1,反应、结晶时间为4小时,选择PEG为分散剂,用量为理论磷酸铁产量的2%,终点pH值为2.0,洗涤用水量为滤饼量的6倍。由化学分析和SEM测定,实验产品满足HG/T4701-2014行业标准要求。  相似文献   

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针对磷尾矿中镁资源浪费问题,以模拟SO_2烟气为提取剂提取磷尾矿中的镁元素。通过单因素试验和正交试验考察反应温度、磷尾矿浆固液比、反应pH、烟气中SO_2质量浓度、烟气流速对SO_2烟气提取磷尾矿中镁元素的影响,得各因素影响大小为:固液比气体流速反应温度pH进口SO_2质量浓度,并确定了较适宜的反应条件:矿浆固液比为1%、反应pH为5、气体流速为600 m L/min、进口烟气中SO_2质量浓度为8 500 mg/m~3、反应温度为50℃。在该条件下反应120 min后,镁元素的浸出率可达97.74%。此外,通过强化研究发现,热处理及加入添加剂能有效提高磷尾矿中镁元素的浸出效率。  相似文献   

3.
明胶钙水制备磷酸二氢钾工艺研究   总被引:2,自引:1,他引:1  
以明胶厂富产钙水和氯化钾为原料,采用复分解法制备磷酸二氢钾。通过单因素实验考察了pH、反应温度、反应时间、液固质量比、钾磷物质的量比等因素对磷收率的影响。结果显示:调节钙水的pH为8.5时,磷的沉淀率最高;控制反应温度为60℃、反应时间为2.5 h、液固质量比为2.5、钾磷物质的量比为1.1时,磷的收率达到90%以上,产品磷酸二氢钾达到农用级标准。  相似文献   

4.
以九水硝酸铁[Fe(NO3)3?9H2O]和柱状5A分子筛为原料采用湿法浸渍法制备Fe?5A催化剂,催化湿式H2O2氧化亚甲基蓝溶液,考察了间歇反应器中pH值和温度对亚甲基蓝转化率的影响及在连续固定床反应器中床层催化剂装填量、进料液流量、温度和亚甲基蓝入口浓度对亚甲基蓝降解性能的影响. 结果表明,在间歇反应中,在亚甲基蓝浓度50 mg/L、温度70℃、pH为2、反应20 min的条件下,亚甲基蓝的转化率为95.9%. 固定床反应中,随温度降低及进料液流量增加,亚甲基蓝转化率降低;随亚甲基蓝入口浓度增加,亚甲基蓝和化学需氧量(COD)的转化率变化幅度很小. 在温度70℃及pH=2、进料液流量4 mL/min、Fe?5A催化剂装填量1.25 g、亚甲基蓝浓度50?300 mg/L、固定床连续运转5 h的条件下,亚甲基蓝的转化率超过98%,COD转化率大于82%,铁浸出浓度低于3.5 mg/L,相同条件下,装填2.5 g 5A分子筛的固定床中50 mg/L亚甲基蓝的转化率仅为73.3%.  相似文献   

5.
闫岩  宋波  于萍 《无机盐工业》2007,39(6):41-43
以硅酸钠和硫酸为原料,采用沉淀法工艺,控制釜底液碱浓度0.2~0.3moL/L、反应温度80-95℃、反应时间30-90min、反应pH8-10、熟化时间10-30min,助剂质量浓度15-30g/L,合成透明牙膏组合物用二氧化硅摩擦剂。着重考察了釜底液碱浓度、助剂质量浓度等对二氧化硅性能的影响。此种二氧化硅摩擦剂的比表面积为30-54m^2/g,邻苯二甲酸二丁酯(DBP)吸收值为0.9-1.4mL/g,平均粒径为6~10μm,辐射牙釉质磨损(RDA)值低于150,pH为6-7,水分质量分数为3%-5%。此种二氧化硅引入到透明牙膏中,体系透光率为40%-85%。  相似文献   

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磷酸锂渣作为低浓度含锂废液的回收产物,因杂质含量高难以直接作为锂电池的生产原料。为充分利用该类磷酸锂渣,以缓解新能源汽车产业的快速发展对锂资源的需求压力,依据锂盐与钙盐在弱酸性条件下具有较大的溶解性差异,向磷酸锂中添加一定量酸和易溶性钙盐,在酸性条件下直接实现磷酸锂渣中锂与磷的分离。实验研究了酸加入量、钙加入量、转化终点pH、转化液固比及转化时间对锂转化效率的影响,发现在酸加入量与固体原料的体积质量比为1.04 mL/g、钙加入量为磷酸锂中磷物质的量的0.9倍、回调pH终点为4.0条件下,锂的转化率可达96.8%。转化液经调节pH除杂、离子交换深度除杂,控制完成液的锂浓度、碳酸钠过滤精度、反应体系温度等,可制备出电池级碳酸锂。碳酸锂产品主成分质量分数约为99.65%,产品质量符合YS/T 582—2013《电池级碳酸锂》的要求,锂的综合回收率达到93.4%。  相似文献   

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中国白云石蕴藏量巨大,白云灰乳碳酸化是白云石碳化法制备轻质碳酸镁、氧化镁等镁化合物的关键步骤之一,关系到镁的产率、产品中钙的含量及生产成本。通过单因素实验和正交实验,研究了碳酸化过程镁的溶出率及重镁水中的钙含量与碳酸化反应温度、反应终点pH、白云灰乳质量浓度的关系,从而为提高碳酸化过程镁的溶出率,实现钙镁的有效分离提供可靠的依据。研究表明:影响镁的溶出率及重镁水中钙含量的主要因素为pH。白云灰乳碳酸化最佳工艺条件:白云灰乳质量浓度为9.00 g/L(以氧化镁计),反应温度为30 ℃,反应终点pH为7.50。在此条件下镁的溶出率为74.49%,重镁水中钙的质量浓度为0.10 g/L。  相似文献   

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朱利华 《安徽化工》2012,38(5):31-33
比较了捞镧除钙法和碳酸盐沉淀法生产低钙碳酸镧的工艺成本,同时考虑收率和氧化钙质量百分含量两项指标,采用正交试验优化出工业中低成本生产低钙碳酸镧的工艺。采用碳铵沉淀,终点pH值6.4,陈化时间0.5小时,反应温度50℃,料液浓度35g/L,一次沉淀收率达到97%,碳酸镧中钙含量降低到0.02%。  相似文献   

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针对以硝酸法湿法磷酸直接制备饲料级磷酸氢钙存在磷氟比(五氧化二磷与氟的质量比)较低的问题,采用化学沉淀法,以钙盐作为脱氟剂,通过间歇实验考察了反应时间、反应温度、反应pH、酸解液中五氧化二磷和氧化钙浓度等因素对酸解液中磷沉淀率和磷氟比的影响。结果表明,反应时间和反应温度的变化对溶液的磷沉淀率和磷氟比影响不大,而降低五氧化二磷和氧化钙的浓度能够有效地提高溶液的磷氟比、降低磷沉淀率。通过对比脱氟溶液制备饲料级磷酸氢钙的收益变化可得出较优操作条件:反应温度为40 ℃,反应时间为20 min,酸解液中五氧化二磷质量分数为7.6%、氧化钙质量分数为3.4%,钙盐中和溶液pH为2.4。在此条件下,脱氟溶液的磷氟比达到230以上、磷损失率小于30%,可为后续饲料级磷酸氢钙的制备提供合格的原料。  相似文献   

10.
聚合氯化铝铁的制备及其应用   总被引:1,自引:0,他引:1  
章小芬 《广州化工》2012,40(8):117-118,128
研究了一种制备聚合氯化铝铁的新工艺。该工艺以聚合氯化铝为碱化剂和Fe(Ⅲ)溶液复合共聚生成PAFC。考察原料配比、反应温度、熟化温度、熟化时间以及pH值对产品性能的影响,确定了最佳的反应条件。制备聚合氯化铝铁的最佳实验条件为:n(Fe3+)∶n(Al3+)=5∶5、pH=4.00、熟化温度为30℃、熟化时间为3 h。对产品进行了水处理实验,考察产品对废水COD和浊度的去除效果,结果表明,COD的去除率与浊度的去除率都很高。  相似文献   

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Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.  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   

15.
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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2008~2009年世界塑料工业进展   总被引:4,自引:1,他引:3  
收集了2008年7月~2009年6月世界塑料工业的相关资料,介绍了2008~2009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、环氧树脂、不饱和聚酯树脂)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   

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.
It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.  相似文献   

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