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1.
水蒸气-微波法制备颗粒活性炭新工艺   总被引:10,自引:0,他引:10  
研究了以椰壳炭化料为原料 ,采用水蒸气 微波法制备颗粒活性炭的可行性。探讨了微波功率、活化时间及水蒸气流量对活性炭性能的影响。得到了水蒸气 微波法制备颗粒活性炭的最佳工艺条件 :微波功率 70 0W、活化时间 3min、水蒸气流量 4.8mL/min。用此工艺条件制得的活性炭碘吸附值 10 31mg/g、亚甲蓝脱色力 10mL/0 .1g、得率 60 .8%。该工艺所需活化时间为传统方法的 1/60 ,得率为传统方法的 2倍左右。  相似文献   

2.
微波辐射-水蒸气法制备烟杆基颗粒活性炭   总被引:11,自引:1,他引:10  
研究了以烟杆废弃物为原料,炭化过程中所产生的木焦油为主的复合粘结剂,采用微波辐射-水蒸气法制备颗粒活性炭的可行性。探讨了微波功率、活化时间以及水蒸气质量流量对颗粒活性炭吸附性能和得率的影响。得到了微波辐射-水蒸气法制备颗粒活性炭的最佳工艺:微波功率700 W,活化时间40 m in,水蒸气质量流量1.70 g/m in。此工艺条件制得的颗粒活性炭,碘吸附值1 060.81 mg/g,亚甲基蓝吸附值175 mL/g,得率30.83%。同时,测定了该颗粒活性炭氮吸附,通过BET法计算了活性炭的比表面积,并通过DFT表征了活性炭的孔结构。结果表明:该活性炭为微孔型,BET比表面积为1 109.22 m2/g,总孔容为0.613 1 mL/g。  相似文献   

3.
探讨了活化温度、活化时间、水蒸气流量对再生后活性炭吸附性能和得率的影响,得到了最佳工艺条件:活化温度1 000℃,活化时间60 min,水蒸气流量2.23 g/min。该工艺条件下再生活性炭的碘吸附值1 174.37 mg/g,亚甲基蓝吸附值200 mL/g,得率为62.87%。再生后活性炭的吸附指标达到国家一级品的标准,其中亚甲基蓝吸附值是国家一级品标准的2.22倍。同时,测定了该活性炭氮吸附,通过BET计算了活性炭的比表面积,通过密度函数理论(DFT)表征了活性炭的孔结构。结果表明:该活性炭为微孔型,BET比表面积为1 254.51 m2/g,总孔容为0.592 6 mL/g。  相似文献   

4.
微波加热烟杆氢氧化钾活化法制备活性炭的研究   总被引:1,自引:0,他引:1  
研究了微波加热烟杆氢氧化钾活化法制备微孔活性炭的新工艺.采用正交实验研究了相关因素对活性炭得率和吸附性能的影响,确定了最佳工艺条件.该工艺将传统方法的预热、干燥、炭化和活化简化为一个过程,所需要的活化时间是传统方法的1/13,产品的亚甲基蓝吸附值是国家一级标准的2.56倍.同时测定了该活性炭的氮吸附等温线,通过H-K方程和密度函数理论(DFT)表征了活性炭的孔结构.结果表明:该活性炭为微孔型,BET比表面积为1402 m2·g-1,总孔容为0.6855 mL·g-1.采用扫描电镜和透射电镜分析了活性炭的微观结构,与氮吸附测定的结果较为一致.  相似文献   

5.
研究了以焦化除尘粉为原料,采用水蒸气为活化剂制备活性炭的可行性.利用正交实验探讨了活化温度、活化时间、水蒸气流量等对活性炭吸附性能的影响.结果表明:影响除尘粉基活性炭制备的主次因素为活化温度、活化时间、水蒸气流量;制备除尘粉基活性炭的最佳条件为活化温度850.C,活化时间90 main,水蒸气流量10.73 mL/min,制备除尘粉基活性炭的碘吸附值为490.5215 mg/g,产率为35.16%.  相似文献   

6.
以酚醛树脂为原料,氢氧化钾为活化剂,采用炭化活化一步法工艺制备酚醛树脂基活性炭.采用TG-DTA、FTIR、N2-BET等表征手段对炭化活化过程、表面官能团、比表面积和孔结构进行了测试和分析.结果表明:碱脂比为2:1,活化温度为750℃,活化时间为60 min工艺条件下制备的酚醛树脂基活性炭对亚甲基蓝和碘的吸附值分别为186 mL·g-1和1 417.96 mg·g-1;所制备的活性炭以微孔为主,其比表面积为1 667 m2·g-1,孔容1.182 cm3·g-1.平均孔径1.835 nm.  相似文献   

7.
研究了制备梧桐树叶基活性炭的影响因素。以深秋梧桐树叶为原料,采用微波辐照磷酸活化法制备了梧桐树叶基活性炭,并对影响梧桐树叶基活性炭吸附性能的因素进行了研究。选取微波功率、辐照时间、液固比、活化剂浓度为影响因素,以碘吸附值作为评价指标,通过正交实验确定了梧桐树叶基活性炭的最佳制备条件;分析了各影响因素对梧桐树叶基活性炭性能的影响程度。以碘吸附值作为评价指标,最佳水平组合为微波功率800 W、辐照时间8 min、活化剂浓度80%、液固比为3 mL.g-1,在此条件下制备的梧桐树叶基活性炭碘吸附值大于618.78 mg.g-1。各影响因素对梧桐树叶基活性炭性能的影响程度依次为活化时间>液固比>微波功率>磷酸浓度。  相似文献   

8.
水蒸气活化法制备稻壳活性炭的研究   总被引:1,自引:0,他引:1  
研究了水蒸气活化法制备稻壳活性炭的工艺条件,探讨了炭化温度、活化温度、活化时间和水蒸气用量对活化效果的影响。最佳工艺条件为:炭化温度 450℃、活化温度 900℃、活化时间 90 min和水蒸气用量为炭化料的1.5倍,制备的活性炭碘吸附值 844 mg/g,亚甲基蓝吸附值 138 mL/g,产品得率 13.9%。这些指标与木质活性炭相当。且投资少,能耗低,具有良好的经济效益与社会效益。  相似文献   

9.
研究了以烟秆废弃物为原料,木焦油为主的复合黏结剂,采用微波辐射二氧化碳法制备颗粒活性炭的可行性.系统探索了微波功率,活化时间以及二氧化碳流量对颗粒活性炭吸附性能和产率的影响,得到了微波辐射二氧化碳法制备颗粒活性炭的最佳工艺条件:微波功率700W,活化时间70min,二氧化碳流量0.15L/min.用此工艺条件制得的颗粒活性炭,碘吸附值为960.30mg/g,亚甲基蓝吸附值13mL/0.1g,产率为43.37%.同时,测定了该颗粒活性炭氮气吸附,通过BET法计算了活性炭的比表面积,并通过DFT表征了活性炭的孔径结果.结果表明,该活性炭为微孔型,BET比表面积为986.65m^2/g,总孔容为0.5152mL/g.  相似文献   

10.
微波加热化学活化法制备活性炭的优化工艺研究   总被引:2,自引:2,他引:0  
研究了微波加热条件下碳酸钾活化制备活性炭的工艺流程。以碳酸钾为活化剂,微波为热源,采用正交试验,研究了浸渍时间、活化剂浓度、微波功率、微波加热时间对活性炭产品性能碘吸附值、亚甲基蓝吸附值、得率的影响规律,得到了最佳工艺条件,即微波功率600 W、微波加热时间6 min、碳酸钾浓度0.20 g/mL、浸渍时间24 h。制得活性炭的碘吸附值可达1189.68 mg/g、亚甲基蓝吸附值190 mL/g、得率29.48%,在该工艺条件下,制备的活性炭试样比表面积为1186.10 m2/g,总孔容积0.624 cm3/g,微孔容积0.407 cm3/g,吸附性能较国家标准有所提高。  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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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   

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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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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