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1.
采用固体超强酸SO_4~(2-)/TiO_2和分子筛改性固体超强酸SO_4~(2-)/TiO_2/USY作为脱氮剂脱除柴油中碱性氮化物,对两者的脱氮效果进行比较,选取合适的脱氮剂,并考察了脱氮剂与柴油质量比、反应温度、搅拌时间和沉降时间对碱性氮化物脱除效果的影响。结果表明,分子筛改性后固体超强酸的脱氮能力有较大提高,且增大脱氮剂与柴油质量比、升高反应温度、延长搅拌时间和沉降时间均可提高柴油中碱性氮化物的脱除率。选取SO_4~(2-)/TiO_2/USY作为脱氮剂,当其与柴油质量比为6:100、反应温度20℃、搅拌时间30 min和沉降时间60 min,柴油中碱性氮的脱除率达78.36%,柴油回收率可达84.37%。  相似文献   

2.
为脱除焦化蜡油中碱性氮化物,采用一种酸性复合络合脱氮剂,以甲苯为溶剂,对焦化蜡油进行脱氮研究。实验考察了反应温度、反应时间、剂油比、沉降时间等条件对焦化蜡油碱性氮化物脱除的影响。实验结果表明:在反应温度为55℃、反应时间为40min、剂油比为1∶4、沉降时间为30min的条件下,焦化蜡油中碱性氮化物的脱除率可达91.34%,焦化蜡油收率达到95.54%。  相似文献   

3.
离子液体脱氮-加氢精制处理高氮焦化汽柴油的研究
  总被引:1,自引:0,他引:1  
采用离子液体对高含氮焦化汽柴油进行脱氮预处理,确定了处理过程适宜脱氮预处理条件,并对预脱氮后焦化汽柴油进行加氢精制工艺评价。结果表明,离子液体预脱氮处理适宜条件为:剂油质量比1∶100,反应温度50 ℃,搅拌时间30 min,沉降时间1.0 h,此条件下,焦化汽柴油的碱氮脱除率为94.9%,且离子液体具有较好的重复使用性。在相同条件下,经预脱氮处理后的柴油与未处理柴油相比,加氢生成油中硫、氮和芳烃含量明显降低,尤其是氮含量低,氮化物的含量高低对催化剂的加氢精制性能有影响。采用离子液体脱氮-加氢精制可深度脱除焦化汽柴油中硫化物与氮化物,降低芳烃含量,改善产品质量,达到生产低硫和低芳烃清洁燃料的目的。
  相似文献   

4.
张浩  颜家保 《广东化工》2008,35(5):21-24
在实验室用WH-2脱氮剂脱除RFCC柴油中的碱性氮化物。考察了剂油比、反应时间、反应温度和静置时间对碱性氮化物脱除和精制后油品透光率的影响。结果表明,增大剂油比、延长反应时间、提高反应温度,均有利于油品中碱性氮化物的脱除,而剂油比和反应时间对脱氮效果的影响要强于反应温度的影响。WH-2脱氮剂对RFCC柴油表现出优良的碱性氮脱除及脱色能力。20℃下,当剂油比为1︰400、反应时间10 min,静置8~10 min,RFCC柴油中的碱性氮脱除率高达97.5%,油品透光率由精制前的3.8%提高到36.4%。通过简单的分离手段,从酸渣中回收到了大部分脱氮剂主剂,可作为脱氮剂成分重复利用。  相似文献   

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用三氯化铁作络合剂,通过络合反应,脱除柴油中的碱性氮化物。通过考察工艺的各影响因素,得到最佳工艺条件:脱氮剂与柴油的体积比为0.9、搅拌时间为18 min、静置时间为30 min、反应温度为60℃。在该工艺条件下,柴油中碱性氮质量分数由85.79μg/g降至5.28μg/g,三氯化铁的脱氮率达到93.8%。  相似文献   

6.
王云芳  刘伟  袁倩  李青松 《应用化工》2011,40(8):1430-1433,1436
以过氧化氢-有机酸体系作氧化剂,采用氧化反应与溶剂萃取相结合的方法,对焦化柴油进行了氧化脱氮研究。考察了不同的氧化体系、氧化温度、氧化时间、氧化剂油比和萃取剂、萃取温度、萃取时间、萃取剂油比对焦化柴油中氮化物脱除效果的影响。结果表明,最适宜的氧化脱氮条件为:过氧化氢-甲酸作为氧化体系,氧化温度为70℃,氧化时间为1 m in,剂油体积比为0.24,V(过氧化氢)/V(有机酸)=0.5。萃取实验条件为:在室温条件下,萃取剂油比为0.8,搅拌5 m in。精制后,柴油回收率达93.33%,总氮脱除率为94.69%。  相似文献   

7.
抚顺页岩油碱性氮化物的脱除   总被引:1,自引:0,他引:1  
王妍  张玫美  宋林  宫红  姜恒 《当代化工》2011,(8):856-858
用LCH-28脱氮剂脱除抚顺页岩油中的碱性氮化物.LCH-28脱氮剂主要由Bronsted酸和Lewis酸(占脱氮剂总重量的0.1%~10%)组成.当剂油质量比为1∶10、反应时间为10 min、反应温度为80~90℃、保温沉降时间为180 min时,碱性氮化物的脱除率达到85.2%,相应的页岩油损失率为18.3%,探...  相似文献   

8.
合成了离子液体N-甲基吡咯烷酮磷酸二氢盐([Hnmp]H_2PO_4),并用红外光谱对其结构进行表征。以焦化柴油为原料,考察其对油品中碱性氮化物的脱除性能,结果表明,离子液体[Hnmp]H_2PO_4能够有效脱除焦化柴油中的碱性氮化物,在剂油质量比为1∶7,反应温度为30℃,反应时间为30 min的条件下,焦化柴油中碱性氮化物的脱除率为93.97%,此时精制油中碱氮质量分数为35μg/g。该离子液体在回收利用4次后,脱氮率仍可达到83%以上。  相似文献   

9.
以硅胶为载体,利用等体积浸渍法负载杂多酸制备3种不同负载型杂多酸吸附剂,采用傅里叶红外光谱和氮气吸附-脱附法对吸附剂负载状态进行了表征。将制备的负载型吸附剂用于焦化蜡油中碱性氮化物的脱除,考察了负载量、反应时间、反应温度和剂油质量比对焦化蜡油脱氮率的影响。结果表明,磷钨酸负载质量分数为40%、反应温度为50℃、反应时间为50min、剂油质量比为1:4的条件下,负载型杂多酸吸附剂能有效脱除焦化蜡油中的碱性氮化物,脱氮率达到89.07%,脱氮油收率达95.54%.  相似文献   

10.
采取了络合脱氮法和吸附脱氮法,以甲苯为稀释溶剂,对煤焦油进行脱氮研究.考察了反应时间、反应温度、剂油比等条件对煤焦油中碱性氮化物脱除的影响.实验结果表明:络合脱氮法反应温度80℃、反应时间30min、剂油比为1∶1的条件下,煤焦油中碱性氮化物的脱除率可达到73.34%,煤焦油的收率达到82.00%.树脂吸附法在剂油为0.8时,对碱性氮化物的脱除率最高,可达到95.1%.  相似文献   

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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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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   

16.
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   

17.
建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。  相似文献   

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