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1.
研究了采用浸渍法制备的ZnO/γ-Al2O3、CuO/γ-Al2O3、γ-Al2O3以及商业Fe2O3脱硫剂对沼气中甲硫醇(CH3SH)的深度脱除性能。结果表明,CuO/γ-Al2O3的脱除性能优于γ-Al2O3、ZnO/γ-Al2O3及商业Fe2O3脱硫剂,但仍无法在较高的空速(GHSV 1200 h-1)下一步完成高浓度CH3SH的深度脱除。为此提出了两段深度脱除法,第一段采用廉价但活性较低的Fe2O3,第二段采用昂贵但高活性的CuO/γ-Al2O3,可将沼气中摩尔分数为100×10-6的CH3SH降低到10×10-9以下,从而能够满足PEMFC分布式电站的要求。还考察了沼气中水分的影响,当水分为2%时,对两段深度脱除法的影响不大。  相似文献   

2.
制备了K2 O-CuO-NiO/γ-Al2 O3羰基硫(COS)转化吸收双功能脱硫剂,并以丙烯为原料,考察脱硫剂在不同条件下脱除液态丙烯中COS的性能,结果表明,与传统的水解-脱硫工艺相比,该脱硫剂可一步脱除烯烃中的COS,具有脱硫净化度高、硫容大和工艺简单等优点.  相似文献   

3.
以前驱物工业活性ZnO和碱式碳酸锌分解的ZnO为脱硫剂活性组分,在引入结构助剂γ-Al_2O_3、碱性助剂K2CO3改性的基础上,制备出转化吸收型氧化锌基脱硫剂。在300℃、空速2000h–1及常压下,考察了活性组分ZnO前驱物种类及不同前驱物制备的助剂γ-Al_2O_3对氧化锌基脱硫剂脱除硫化物性能的影响。结果表明:改性氧化锌基脱硫剂的孔隙结构和碱性显著影响其脱硫性能。与工业活性ZnO制备的氧化锌脱硫剂相比,以碱式碳酸锌分解的ZnO制备的脱硫剂对硫化氢的脱除效率和穿透硫容更高,穿透硫容约增加10倍。不同前驱物制备的γ-Al_2O_3对氧化锌基脱硫剂脱硫性能有较大影响。其中,拟薄水铝石分解的γ-Al_2O_3显著提高了氧化锌基脱硫剂脱硫性能,穿透硫容达12.18%。以碱式碳酸锌分解ZnO为活性组分,添加拟薄水铝石分解的γ-Al_2O_3和碱性助剂K2CO3制备的改性氧化锌基脱硫剂对COS的脱除起到转化与吸收作用,COS转化率达99.98%,穿透硫容为4.03%。  相似文献   

4.
以纳米CuO/ZnO作为去除H2S的活性组分,考察了反应温度、空速、氧分压等反应条件和掺铜量对纳米CuO/ZnO脱硫性能的影响,并分析了CuO对脱硫剂脱硫机理的影响。结果表明:脱硫剂TZ2(Cu:Zn物质的量比为1:18.40)有较高的脱硫性能;空速越低脱硫性能越高;反应温度由25℃升高到120℃,脱硫性能先下降后升高,120℃的脱硫性能略高于25℃;氧分压为10%时,有最佳的脱硫性能;CuO的加入增大了脱硫产物向多硫化物及单质硫的转化。  相似文献   

5.
郝少军  吴锋  陈实  孙杰  刘媛 《辽宁化工》2004,33(3):127-129,179
研究了甲醇水蒸气重整制氢反应过程中各种因素对Cu/ZnO/Al2O3催化剂的活性和选择性的影响.结果表明:Cu/Zn比为2.0的催化剂在250℃反应时,催化剂效果较好,最合适反应条件是:压力0.1 MPa,温度250℃,n(H2O)∶n(CH3OH)=1.0~1.2,液体流速0.1 mL/min.在Cu/ZnO/Al2O3催化剂上,甲醇水蒸气重整、甲醇分解和水气转换反应随反应条件的不同而发生相互抑制或促进作用.  相似文献   

6.
用共沉淀法加浸渍法制成Ni质量分数分别为0,5%,10%的Cu - Zn - Ni/Al2 O3复合三元脱硫剂,通过天然气脱硫实验,研究了它们的脱硫性能.实验结果表明,合适的Ni含量会增强Cu - Zn-Ni/Al2O3脱硫剂的超深度脱硫性能(小于10×10-9m3/m3),并且随着温度的升高,脱硫性能逐渐增强,最终会...  相似文献   

7.
以活性炭(AC)为载体,用FeSO_4·7H_2O为原料,采用沉淀法制备Fe负载脱硫剂,通过XRD、FTIR、FE-SEM、ICP、H_2-TPR等方法对脱硫剂进行表征。从制备方法和焙烧温度的角度,研究脱硫剂低温脱除CS_2的性能以及造成其差异的原因。结果表明:采用FeSO_4先沉淀后焙烧,焙烧气氛是氮气的γ-Fe_2O_3/AC-N_2法生成的γ-Fe_2O_3结晶度最高,并且有效地增加了活性炭表面碱性基团数量,提高了负载量和分散性,使脱硫效果大大提升,当焙烧时有O_2存在会生成α-Fe_2O_3降低脱硫剂脱除CS_2的活性;使用γ-Fe_2O_3/AC-N_2法焙烧温度在500℃时,结晶度最高,脱硫剂的脱硫效果最好,吸附量达到40.41mg/g,当温度超过500℃时生成了Fe_3O_4,降低了脱硫效果,用4种动力学模型对γ-Fe_2O_3/AC在活性炭载体上的脱硫过程进行动力学描述,发现Elovich模型可以更好地描述CS_2在脱硫剂上的脱硫过程,其化学控制是主要因素。  相似文献   

8.
用热重法研究了还原后的NT70 5型脱硫剂脱除合成气中H2 S的脱硫反应本征动力学。在很强的还原氛围中 ,4 0 0℃的条件下 ,脱硫剂中的Fe2 O3 被还原为Fe3 O4,并进一步还原为FeO ,最终还原为单质Fe。实验采用 10 0 12 0目的小颗粒 ,在 2 80 4 0 0℃范围内 ,原料气H2 S质量浓度为 0 995 5 2 g/m3 的条件下进行。实验数据用未反应收缩核模型处理 ,结果表明 ,小颗粒脱硫剂的脱硫反应速率为化学反应控制 ,脱硫反应为一级反应  相似文献   

9.
SQ105型精脱硫剂的实验室研究   总被引:1,自引:1,他引:0  
介绍了SQ105型脱硫剂常温脱除H2S、COS和CH3SH的实验室研究以及在不同气体中脱除COS的性能。结果表明,该脱硫剂在常温条件下脱除COS的反应速率较低;反应温度40 ℃时,该脱硫剂显示较好的脱除COS性能,具有硫容大、脱除率高和气氛效应小的特点。  相似文献   

10.
利用等体积浸渍法制备了一系列Fe/γ-Al2O3催化剂。在温度为30℃时考察了催化剂中Fe含量对苯酚模拟废水COD去除率的影响,发现Fe0.01/γ-Al2O3具有较高的催化活性。研究了苯酚废水的初始pH,反应温度,是否添加H2O2以及是否通入空气时Fe0.01/γ-Al2O3催化剂的性能。结果表明,在反应初始pH为3,温度为30℃,加入100μL H2O2并通入空气的条件下,反应1 h后,苯酚废水COD的去除率最高,约为65%。给出了苯酚在催化剂表面的降解反应模型。  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   

13.
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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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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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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