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1.
工业煤半焦经880℃水蒸气活化、等体积浸渍硝酸钙溶液、干燥、煅烧制得新型低温Ca/AC脱硫剂。考察了制备参数(煅烧温度和载钙量)对脱硫活性的影响,并对脱硫剂进行了XRD表征。结果表明:经300℃煅烧的Ca/AC脱硫剂具有最高的脱硫活性,低于300℃煅烧,前驱体可能未完全分解,高于300℃煅烧,可能会使骨架炭烧失,二者均导致脱硫活性降低。Ca/AC脱硫剂适宜的载铁量为3%-7%,大于7%担载量使脱硫剂中钙利用率下降,脱硫活性下降。  相似文献   

2.
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   

3.
采用直接煅烧法、还原法及添加脱硫剂煅烧法对电解锰压滤渣进行了高温脱硫,研究了不同方法得到的脱硫产物的物相、残硫量和活性,并比较了几种方法的工业适用性。结果表明:直接煅烧法的脱硫渣和坩埚粘连严重,实际操作困难;加入煤粉并没有改善脱硫渣和坩埚的粘连问题,且脱硫渣中残硫量高;石灰石虽能减弱脱硫渣和坩埚的粘连,但由于生成惰性物质石英,降低了脱硫渣的活性;采用铝矾土作为脱硫剂进行脱硫,脱硫渣的残硫量低,脱硫渣和坩埚不粘连,脱硫渣活性高。铝矾土添加量为42%(质量分数),脱硫温度为1 250 ℃,脱硫保温时间为5 min时,脱硫渣中硫含量为0.089 4%(质量分数),达到脱硫要求。  相似文献   

4.
复合金属氧化物脱除羰基硫的研究   总被引:6,自引:0,他引:6  
采用共沉淀法制备铁锰复合金属氧化物脱硫剂,从温度、空速和羰基硫浓度几个方面考察对脱硫剂脱硫性能的影响.实验结果表明,该脱硫剂在250℃~350℃,强还原性气氛下,具有较高的有机硫脱硫精度和较大硫容.实验还考察了氧化锌、氧化铜、氧化镍和氧化铈几种添加剂对脱硫剂脱硫效果影响,结果表明,脱硫剂中添加氧化镍和氧化铈后脱硫精度有较大提高,出口羰基硫浓度低于0.1×10-6,添加氧化铜和氧化锌的脱硫精度为0.2×10-6;此外,添加氧化锌脱硫剂硫容较大,穿透硫容为25%,而添加氧化铈的脱硫剂硫容相对较小.  相似文献   

5.
金属氧化物助剂对Cu/AC脱硫活性的影响   总被引:4,自引:0,他引:4  
活性焦担载氧化钢新型Cu/AC脱硫剂,在工业锅炉烟气最适宜的脱硫温度下具有高的脱硫活性.为进一步提高Cu/AC对SO2的吸附硫容,制备了一系列添加不同金属氧化物助剂的脱硫剂,并对其在 200 ℃下的脱硫活性分别进行了评价.结果表明,添加 K, Na或 Al后的脱硫剂硫容出现明显增加,且对高载铜量脱硫剂硫容增加幅度明显高于低载铜量脱硫剂.借助 TPD和 XRD表征技术,发现添加 K, Na, Al助剂后硫容的增加并非源于所添加 K, Na, Al与 SO2的反应,主要归因于硝酸铜与 K, Na或 Al盐溶液的共同浸渍,改善了铜物种在 AC表面的分散性,从而提高了活性.  相似文献   

6.
采用钢厂的废物赤泥为活性成分,添加不同的黏结剂及造孔剂制备出了高温煤气脱硫剂。对制备的脱硫剂的脱硫活性和机械强度进行了测试与表征。结果表明,以赤泥为原料制备的脱硫剂是一种性能优良的脱硫剂。黏结剂的添加不仅能够提高脱硫剂的抗粉化性能,而且也可通过改变脱硫剂的织构来影响脱硫效果,分别添加三种黏结剂后,脱硫剂的机械强度最高的由188 N/cm提高到230 N/cm。同时通过对脱硫剂的硫容和穿透曲线进行的综合考察,发现高机械强度的脱硫剂,并不一定有高的硫容和脱硫效率,而适宜的强度能够提高脱硫剂的脱硫效率。  相似文献   

7.
CuO脱硫剂脱除SO2的工艺条件研究   总被引:3,自引:0,他引:3  
用干混法制备了一系列以CuO为主要活性组分的SO2脱硫剂,考察了脱硫剂反应条件对脱硫活性的影响。结果表明,烟气中的O2对于CuO脱硫剂的活性有显著的促进作用,能增加脱硫剂硫容;脱硫剂显示较高活性的温度范围350~500 ℃;空速在1 800~4 200 h-1操作范围内,脱硫剂可维持较高且比较稳定的硫容。  相似文献   

8.
通过优化制备工艺和制备条件,提高氧化锌脱硫剂的脱硫性能。以乙二酸和乙酸锌为原料,采用固相法制备了乙二酸锌前驱体;添加助剂和粘结剂后,通过微波焙烧制备了氧化锌中高温煤气脱硫剂。采用单因素法研究了微波功率、焙烧温度、焙烧时间以及活性组分质量分数对脱硫剂性能的影响,并利用响应面法探讨了各因素及其交互作用对脱硫剂穿透时间和硫容的影响,确定了氧化锌脱硫剂的最佳制备工艺:微波功率1 300 W,焙烧温度550℃,焙烧时间60 min,活性组分质量分数30%。采用回归分析法建立了回归模型,并通过试验验证了模型的可靠性。结果表明:模型预测值与实测值接近;焙烧温度、焙烧时间和活性组分质量分数对脱硫剂穿透时间有显著的影响;焙烧温度和焙烧时间、焙烧温度和活性组分质量分数二者的交互作用均比较显著。  相似文献   

9.
高活性镍基加氢催化剂是以硅藻土为载体、镍为活性组分采用共沉淀法制备的催化剂。考察了硅藻土比表面积、镍与硅藻土质量比、催化剂前驱体煅烧温度、催化剂前驱体还原温度等条件对催化剂活性的影响。通过实验数据分析,最终确定了高活性镍基加氢催化剂的最佳制备条件:硅藻土比表面积为284.2 m2/g,镍与硅藻土质量比为0.8,催化剂前驱体煅烧温度为500℃,催化剂前驱体还原温度为600℃。在此条件下制备的镍基加氢催化剂最优,经过棕榈油加氢评价后碘值最小,说明催化剂活性最高。  相似文献   

10.
用共沉淀法制备脱氧脱硫双功能精脱硫剂前驱物,按一定比例加入催化剂助剂、粘接剂及扩孔剂混捏成型,经500~550℃焙烧得脱氧脱硫双功能精硫剂成品。考察了温度、压力和硫含量对活性的影响。结果表明,在温度不高于200℃,空速3000 h~(-1),压力≥0.5 MPa的条件下,可将焦炉气和转炉混合气中的总硫脱至0.03 mg/m~3,O_2脱至0.03%以下;长周期实验和工业应用表明,双功能精脱硫剂具有脱氧脱硫精度高,活性稳定性好的特点。  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   

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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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