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1.
通过高温煅烧三聚氰胺的方法制备氮化碳。以氮化碳,甲酸为催化剂、过氧化氢为氧化剂、DMF为萃取剂超声氧化萃取脱除模拟油中的二苯并噻吩(DBT)。考察了反应温度、反应时间、氧化剂加入量、催化剂加入等因素对脱硫率的影响。结果表明,当模拟油:双氧水:甲酸的体积比为100∶3∶6、氮化碳为0.03 g、反应温度为50℃、反应时间为20 min、萃取剂DMF剂油比为0.25∶1时,二苯并噻吩的脱除率可以达到82.2%。催化剂重复使用3次后,脱硫率仍然保持在75%。  相似文献   

2.
通过简单加热并搅拌甲基咪唑盐酸盐和草酸的混合物合成了甲基咪唑盐酸盐/草酸([HMIM]Cl/H_2C_2O_4)型酸性低共熔溶剂,以[HMIM]Cl/H_2C_2O_4为萃取剂和催化剂、H_2O_2为氧化剂催化氧化法脱除模拟油中的二苯并噻吩,考察不同的脱硫体系、反应温度、催化剂加入量、氧硫比、模拟油中含硫化合物类型对脱硫率的影响。实验表明,在反应温度为40℃、模拟油量为5 ml、[HMIM]Cl/H_2C_2O_4加入量为1.25 ml、O/S=12、反应时间为140 min的最佳反应条件下二苯并噻吩的脱除率可以达到92.2%。动力学分析表明,该氧化脱硫体系符合一级反应动力学方程。循环使用7次后催化剂的活性没有明显降低。  相似文献   

3.
以磷钨酸和蔗糖为原料,利用水热法制备了H_3PW_(12)O_(40)@C。采用XRD、SEM、FT-IR对其结构进行表征。以H_3PW_(12)O_(40)@C为催化剂,过氧化氢为氧化剂,1-丁基-3-甲基咪唑氟硼酸盐([Bmim]BF_4)离子液体为萃取剂氧化脱除模拟油中的二苯并噻吩。对氧化脱硫体系进行了优化,结果表明,在模拟油为5.0 m L,n(H_2O_2)/n(S)为8,催化剂质量为0.04 g,离子液体用量为1.50 m L,反应温度为60℃,反应时间为180 min的最优条件下,二苯并噻吩的脱除率达到81.3%。同时,考察了催化剂的循环使用性能并对氧化脱硫机理进行研究。  相似文献   

4.
通过简单加热并搅拌甲基咪唑盐酸盐和草酸的混合物合成了甲基咪唑盐酸盐/草酸([HMIM]Cl/H2C2O4)型酸性低共熔溶剂,以[HMIM]Cl/H2C2O4为萃取剂和催化剂、H2O2为氧化剂催化氧化法脱除模拟油中的二苯并噻吩,考察不同的脱硫体系、反应温度、催化剂加入量、氧硫比、模拟油中含硫化合物类型对脱硫率的影响。实验表明,在反应温度为40℃、模拟油量为5 ml、[HMIM]Cl/H2C2O4加入量为1.25 ml、O/S 12、反应时间为140 min的最佳反应条件下二苯并噻吩的脱除率可以达到92.2%。动力学分析表明,该氧化脱硫体系符合一级反应动力学方程。循环使用7次后催化剂的活性没有明显降低。  相似文献   

5.
采用高温煅烧MoO_3和g-C_3N_4混合物制备了不同MoO_3含量的MoO_3/g-C_3N_4催化剂。采用X射线粉末衍射(XRD)、傅里叶红外光谱(FTIR)、扫描电镜(SEM)和N2吸附脱附对催化剂的结构和性能进行了表征。以MoO_3/g-C_3N_4作为催化剂,H_2O2为氧化剂,离子液体为萃取剂研究了反应体系的氧化脱硫性能。这项研究中考察了不同煅烧温度下制得的催化剂、负载量、氧化剂使用量、催化剂加入量、反应温度、萃取剂使用量、反应时间、硫化物类型等不同反应参数对脱硫率的影响。结果表明,在H_2O2的使用量为0.2m L,MoO_3/g-C_3N_4加入量为0.03g,1-乙基-3-甲基咪唑硫酸乙酯离子液体1.0m L,反应温度为70℃,反应时间60min的最佳工艺条件下,24%-MoO_3/g-C_3N_4催化剂脱硫率可以达到94.8%,催化剂循环使用5次后活性没有明显下降。此外,研究了MoO_3/g-C_3N_4在离子液体中的催化氧化反应机理。  相似文献   

6.
《应用化工》2022,(10):2527-2532
使用溴化1-苄基-3-甲基咪唑与硅钨酸沉淀反应制备了一种杂多酸盐催化剂,采用红外光谱对催化剂进行物性表征,采用萃取耦合氧化反应体系考察催化剂用量及不同体系对脱硫效果的影响。结果表明,最佳条件下二苯并噻吩(DBT)的脱除率为90.28%,且不同温度下DBT的脱除率均大于苯并噻吩(BT)。同时通过反应动力学研究得出该体系中的二苯并噻吩氧化反应为一级反应,表观活化能为21.262 kJ/mol。  相似文献   

7.
通过简单加热1-乙基-3-甲基咪唑硫酸乙酯(EMIES)离子液体和3-苯丙酸(C_9H_(10)O_2)的混合物,制备了一系列酸性低共熔溶剂EMIES/nC_9H_(10)O_2(n=0.25,0.5,1,2,4)。通过FTIR,~1H NMR和TGA的表征,确定EMIES/nC_9H_(10)O_2的结构。以该低共熔溶剂为催化剂和萃取剂,H_2O_2为氧化剂,组成氧化-萃取脱硫体系,用于脱除模拟油中的硫化物。考察了原料配比、反应温度、氧硫比(O/S)、低共熔溶剂加入量和不同硫化物对脱硫性能的影响。结果表明,在EMIES和C_9H_(10)O_2摩尔比为1∶1,反应温度为50℃,O/S比为8,低共熔溶剂加入量为1.5 g和模拟油5 ml的反应条件下,二苯并噻吩、4,6-二甲基二苯并噻吩和苯并噻吩的脱除率分别为94.8%、91.6%和46.4%。低共熔溶剂可循环使用6次,活性无明显下降。此外,对该氧化-萃取脱硫体系的脱硫机理进行了探讨。  相似文献   

8.
考察了1-乙基-3-甲基咪唑溴络合氯化亚铁([EMIM]Br-FeCl2)离子液体对含有噻吩(TS)、苯并噻吩(BT)和二苯并噻吩(DBT)模拟油及FCC汽油的萃取脱硫效果。实验结果表明:在40℃条件下萃取4 h,当剂油质量比为2∶1时,噻吩的脱除率为25.6%;当剂油质量比为2∶5时,苯并噻吩的脱除率达到72.4%,二苯并噻吩的脱除率达到79.9%。按剂油质量比2∶1应用于实际汽油,单级萃取脱硫率为50.3%~54.5%,5级萃取脱硫率为89.3%~91.3%。对使用过的离子液体进行再生处理,再生后离子液体可以使用10次以上。  相似文献   

9.
采用溶胶-凝胶法制备锰离子改性的Si O2负载的磷钼酸催化剂,并采用傅里叶红外光谱(FT-IR)、X射线衍射(XRD)和扫描电镜(SEM)等对催化剂进行表征。考察了催化剂用量、过氧化氢用量、反应温度和反应时间等对模型油(苯并噻吩和二苯并噻吩)和直馏柴油氧化脱硫的影响。结果表明:锰离子改性后,催化剂仍然保持了磷钼酸的Keggin型结构,其活性中心的分散度和比表面积均增加;不同反应条件对模型油的氧化脱硫均有影响,且二苯并噻吩(DBT)较苯并噻吩(BT)更易脱除。正交试验结果显示,各因素对柴油脱硫率的影响由大到小依次为反应时间催化剂用量过氧化氢用量反应温度。在催化剂0.15 g,过氧化氢0.25 mL和反应温度70℃的条件下,反应时间4 h后,直馏柴油的脱硫率达90.3%,油品回收率不低于98%。  相似文献   

10.
以二氧化硅负载硼钨酸(HBW)为催化剂,H2O2为氧化剂,以苯并噻吩(BT)模拟柴油中有机硫化物,考察了二氧化硅负载硼钨酸在H2O2为氧化剂存在下氧化脱硫的催化活性,探索了反应温度、反应时间、催化剂负载量和氧化剂V(H2O2)与模拟柴油V(O)比对脱硫率的影响。实验结果表明:二氧化硅负载硼钨酸对苯并噻吩模拟柴油脱硫的最佳条件为硼钨酸负载量75%,反应时间2 h,反应温度50℃,V(H2O2)∶V(O)=1∶5,BT的脱硫率达到97.6%。  相似文献   

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12.
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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14.
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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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.
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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