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1.
BrΦnsted酸离子液体催化废油脂制备生物柴油   总被引:4,自引:0,他引:4  
采用磺酸类BrΦnsted酸离子液体作为催化剂,研究了不同工艺条件下催化废油脂制备生物柴油的过程. 以地沟油为原料,醇/油摩尔比12:1,催化剂用量为油质量的2%,在140℃下反应5 h,产物中脂肪酸甲酯的含量达到86.8%. 在同样的反应条件下,催化剂重复使用9次后其活性无明显变化. 该催化剂对废油脂制备生物柴油具有较高的催化活性和良好的重复使用性能.  相似文献   

2.
提出了一种清洁、环境友好的餐饮业废油脂制备生物柴油的方法和工艺.以磁性固体超强酸SO2-4/TiO2-Fe3O4为非均相催化剂,以餐饮业废油脂为原料与甲醇进行酯交换反应制备生物柴油;利用三因素一次回归正交设计实验方法,考察了反应温度、甲醇用量、催化剂用量对废油脂酯转化率的影响,确定了制备生物柴油的最佳反应条件;通过对实验结果的处理,求出了回归方程;数理统计分析表明回归方程可靠适用;同时利用IR、XRD、SEM、EDS等对磁性固体超强酸SO2-4/TiO2-Fe3O4催化剂的结构进行了表征.与传统的均相催化剂(H2SO4、NaOH) 相比,磁性固体超强酸具有催化活性高、易于分离、可重复使用的特点,是制备生物柴油的环境友好型固体酸催化剂.  相似文献   

3.
废弃油脂超临界法制备生物柴油研究   总被引:2,自引:0,他引:2  
以废弃油脂为原料,利用超临界法制备生物柴油.通过单因素实验及正交实验研究了醇油摩尔比、反应压力、催化剂用量、反应时间、反应温度等因素对生物柴油产率的影响.结果表明,在实验范围内各影响因素对生物柴油产率作用的大小依次为:反应温度>反应压力>催化剂用量>反应时间>醇油摩尔比.废弃油脂超临界法制备生物柴油的最佳工艺条件为:反应温度240℃,反应压力10MPa,反应时间6min,催化剂用量0.06%,醇油摩尔比40/1.在此条件下,生物柴油产率达到99.37%.  相似文献   

4.
B酸离子液体[HSO_3-bpy]CF_3SO_3催化麻疯油制备生物柴油   总被引:1,自引:0,他引:1  
以麻疯油为原料,离子液体[HSO3-bpy]CF3SO3为催化剂通过酯交换反应制备生物柴油。通过正交实验考察了催化剂用量、醇油摩尔比、反应温度、反应时间等4个因素对反应的影响。同时以[HSO3-bpy]CF3SO3为催化剂兼溶剂,优化了生物柴油的合成条件。结果显示:反应温度为140℃、催化剂用量为油脂质量的5%、醇油摩尔比为15:1、反应5h,单次酯交换制备生物柴油,收率可达到90.4%,在相同的反应条件下,催化剂重复使用6次后其催化活性无明显变化,且产品质量达到美国ASTM生物柴油标准的相关指标。  相似文献   

5.
本文主要研究固体酸催化剂催化废油脂酯交换反应,利用浸渍法制备浓硫酸固载活性炭催化剂。同时对催化剂进行红外光谱表征和热重分析。最后通过单因素实验控制反应条件来制备生物柴油,得到酯交换的适宜反应条件为:n(醇)/n(油)=20/1,m(催化剂)/m(油)=5/100,t(反应时间)=4 h,T(反应温度)=75℃,在此条件下,生物柴油的产率为89.93%。  相似文献   

6.
文章采用与硫酸性质相近的固体酸硫酸氢钠作催化剂,催化野油菜籽油制备生物柴油。综合考察了反应时间、催化剂用量、醇油摩尔比、反应温度对生物柴油得率的影响,进而以正交试验优化得到利用野油菜籽油制备生物柴油的最佳条件:反应时间15 h,催化剂用量为油脂重量的9%,醇油摩尔比12∶1,反应温度130℃。在此条件下,生物柴油的得率达到98.06%,并且催化剂重复使用三次以上生物柴油得率无明显变化。采用气相色谱-质谱(GC/MS)联用分析,所制生物柴油主要成分为8-十八烯酸甲酯和9,12-十六碳二烯酸甲酯。产品达到柴油机燃料用调和用生物柴油国家标准(BD100)国家标准。  相似文献   

7.
高酸值废油脂的对甲苯磺酸催化乙酯化反应   总被引:1,自引:0,他引:1  
邓秀琴  喻育红 《应用化工》2013,42(6):1114-1117
以价格低廉易得的废油脂为原料制备生物柴油,不但能带来巨大的经济效益,而且符合绿色环保的产业发展要求。但是废油脂通常具有较高的酸值,因此在以碱催化酯交换法制备生物柴油之前,需对高酸值原料油进行降酸处理。考察了相关条件对油脂预酯化反应的影响。结果表明,最佳条件为:催化剂加入量为4%,反应时间为90 min,带水剂加入量为10%,乙醇醇酸摩尔比为6∶1。  相似文献   

8.
用密闭的高压反应器,研究了以浓H_2SO_4为催化剂,在高于甲醇正常沸点的条件下,餐饮废油一步法直接甲酯化制备生物柴油技术。重点考查了反应温度、反应时间、催化剂用量和醇油比等因素对生物柴油制备反应的影响。结果表明,提高反应温度能强化生物柴油的制备过程,促进目的产物脂肪酸甲酯的生成,使高酸值的原料经一次反应直接转化为生物柴油。当催化剂浓H_2SO_4用量为1.0%(质量)、醇油摩尔比为8∶1、在120℃反应2h后,生物柴油的最高收率达到86.0%。该方法能缩短工艺流程,显著减少反应时间,提高餐饮废油脂利用的经济效益,具有显著的优点。  相似文献   

9.
以不同油脂为原料制备生物柴油,对各类催化剂催化活性进行了研究;利用气相色谱及化学分析法,对各类催化剂进行了优化组合。结果表明,对于酸值低于10的油脂,碱性催化剂由于催化效果好,反应时间短,是首选的理想催化剂;而对于酸值高于10的油脂,无论酸性还是碱性催化剂,均难于在短时间内完成酯化反应。自配的NG催化剂,在质量分类(相对油脂质量)为0.1%,反应温度180℃,反应时间为2 h的条件下,反应转化率达到93%,有望作为亚临界状态下制备生物柴油理想的催化剂。  相似文献   

10.
以浓硫酸为改性剂,采用化学键合方法对固体分子筛4A表面进行磺化改性。以此为催化剂催化油酸-菜籽油模拟的高酸值油脂-甲醇酯交换反应制备生物柴油。结果表明,反应体系在65℃,醇/油摩尔比为16∶1条件下反应6h,生物柴油产率可达到88.39%,比相同条件下未改性的分子筛4A和浓硫酸催化高酸油脂制备的生物柴油产率明显提高。  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   

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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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   

20.
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   

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