合成气直接制取低碳烯烃的铁基负载型催化剂的制备与性能

采用浸渍法制备了合成气直接制取低碳烯烃的铁基负载型催化剂,在固定床反应器中考察了载体、助剂、焙烧温度及反应温度与压力、原料气空速对催化性能的影响,并对其进行了表征. 结果表明,焙烧温度对催化剂活性有重要影响,FeK/ZSM-5催化剂经500℃焙烧3 h后具有最佳的催化活性,提高反应压力可明显提高活性,而增加原料气空速活性明显降低;添加助剂K和Mn明显提高了催化剂的低碳烯烃选择性,在H2/CO=2(j)、反应温度380℃、压力1.0 MPa、原料气空速4400 h-1条件下,FeMnK/ZSM-5可将CO转化率从Fe/ZSM-5催化剂的18.7%升至63.8%, C2=~C3=选择性从4.8%升至14.1%.     

钴基催化剂的制备及性能评价

以γ-Al_2O_3为载体,采用等体积浸渍法制备F-T合成钴基催化剂,在F-T合成小型固定床反应装置评价催化剂。考察并优化了钴源、焙烧温度、钴负载量、反应温度和原料气空速等工艺条件对催化荆活性和F-T合成产物收率的影响,测试了Co/γ-Al_2O_3催化剂的稳定性。结果表明,最佳制备条件:以硝酸钴为钴源,焙烧温度400℃,钴负载质量分数10%。在温度230℃、压力2 MPa、原料气组成n(H_2)∶n(CO)=2和反应空速1 800 h~(-1)的条件下,进行60 h运转实验,CO转化率可达69.1%,C_5~+烃收率高达89.6%。     

C3H6选择性催化还原NO催化剂 Ag/γ-Al2O3的研究

采用低负载量的(0～3%)Ag/γ-Al2O3体系作为C3H6选择性催化还原(C3H6-SCR)NO的催化剂,考察了银负载量、反应温度、空速对NO转化率的影响.同时对于原料气中氧的作用进行了研究.结果表明:银负载量为1.5%时,催化剂表现出最高的反应活性;在考察的条件范围内,原料气中含氧对NO的还原有促进作用,适宜的氧浓度为0.27%;反应温度的过高会导致还原气中C3H6大幅度转化为CO2.     

喷雾干燥铁催化剂F-T合成反应的研究

采用转环式无梯度反应器对沉淀 -喷雾干燥技术相结合制备的 Fe- Cu- K- Si O2 催化剂在反应温度 2 5 0℃～ 2 80℃ ,压力 0 .5 MPa～ 1 .5 MPa,H2 /CO比 0 .1 9～ 1 .35和原料气空速 1 0 0 0h-1～ 2 5 0 0 h-1的条件下对 Fisher- Tropsch合成反应性能进行了考察 .结果表明 ,该催化剂具有较高的 F- T反应活性和水煤气交换 ( WGS)反应活性 ,产物烃分布显示出高的烯烃选择性 ,说明该条件有利于初级烯烃的脱附和低碳烃的生成 ,一定程度上减少了烯烃再吸附的链增长反应 .还考察了各种反应条件对产物碳数分布的影响 ,并观察到了运行过程中催化剂较低的失活速率 .     

RFT-2固定床费托合成催化剂中试应用研究

对RFT-2固定床费托合成催化剂进行中试应用研究,对其反应性能和运转稳定性能进行考察。结果表明,在合成气空速750～800h-1、原料气转化率93%左右的工况下,C3＋烃类选择性达90%以上,C5＋液体烃选择性达86%以上,催化剂具有较好的反应性能;在超过1 000 h的稳定性运转考察过程中,催化剂活性、选择性未见明显...     

C5抽余液选择性加氢工艺研究

通过对C5抽余液选择性加氢的工艺条件试验,考察了入口温度、氢油体积比、体积空速和反应压力等主要工艺条件对反应转化率的影响。得出适宜的工艺条件:在稀释进料,C5/环己烷为1/2,反应入口温度为44℃,氢油体积比(对原料C5)为500∶1,体积空速(对C5原料)为1.0 h-1,反应压力为基准+2.0 MPa,加氢后的C5组分中二烯烃及炔烃总含量小于1.0%。1 000 h的稳定性实验证明该催化剂具有很好的活性稳定性。     

Pd／Al2O3催化剂上裂解C5馏分选择性加氢反应研究

研究了负载在Al2O3载体上的贵金属钯（Pd）基催化剂在裂解C5馏分中选择性加氢反应中的性能。结果表明,Pd／Al2O3催化剂上可进行选择性加氢的反应条件区域为压力0．5～1．0MPa、体积空速2—4h^-1、氢油体积比100：1～300：1和反应温度为55—65℃,在此反应条件下,炔烃能被完全加氢去除,同时二烯烃发生部分转化,转化产物主要为单烯烃,其中二烯烃转化的产物主要是热力学相对稳定的单烯烃;在选定的反应条件中,随温度升高、压力增加、氢油比增加,炔烃、二烯烃转化率提高;而随液时空速增加,二烯烃转化率有所下降;在各反应条件中,温度和压力对催化剂加氢性能影响较为显著;制备的Pd／Al2O3催化剂对于炔烃和二烯烃具有好的选择性加氢能力,可能原因一方面是由于反应条件选择较缓和,另一方面是原料中硫的存在。     

烯烃歧化制备α-烯烃新方法研究

制备了一种负载型Re基催化剂Re2O7/γ-Al2O3,用于直链内烯烃与乙烯歧化制备α-烯烃。结果表明,以C11～C12直链内烯烃为原料,反应温度60℃,反应体积空速1 h-1,反应压力3 MPa的条件下,C11～C12烯烃的单程转化率达到90.0%,歧化选择性达到85.98%。     

Cd改性拉长石催化甲烷裂解制C2烃

以Cd改性拉长石(Cd/Lab)为甲烷裂解催化剂制C2烃,通过XRD、XPS、TEM及GC对催化剂的结构、形貌和催化性能进行了表征与测试。利用固定床反应装置考察了金属掺杂量、反应温度、原料气空速等因素对拉长石催化甲烷裂解制C_2烃的影响。结果表明,当原料气空速为1 L/h、反应温度1073 K时,天然拉长石和Cd质量分数为1.0%的Cd改性拉长石催化甲烷裂解的转化率分别为3.32%和6.41%,且C_2烃的选择性99%。XRD、XPS、TEM等表征和催化性能结果表明,Cd2+进入到拉长石的碱金属位点,证明拉长石催化甲烷裂解的有效活性位点是碱金属位点。     

用于合成气制高值产物的InZrOx 氧化物制备及性能

以四水合硝酸铟和五水合硝酸锆为原料，通过共沉淀法和水热法制备InZrOx氧化物，并在最佳制备条件下探究煅烧温度对合成氧化物的影响，与SAPO-34分子筛结合为双功能催化剂用于用于合成气催化转化制高值产物。采用XRD、SEM-EDS、HRTEM、XPS和BET对氧化物的织构性质、晶体结构、形貌特征及表面电荷进行表征与测试，并在固定床反应器中系统研究了空速、原料气氢碳比（物质的量）、氧化物与分子筛质量比、反应温度及反应压力对催化效果的影响规律。结果表明，共沉淀法得到的氧化物在各方面表现均优于水热法，最佳煅烧温度为550 ℃。在空速为2000 mL/(gcat·h)、原料气氢碳比（物质的量）为3：1、m(InZrOx)：m(SAPO-34)=1：1、400 ℃、3 MPa的反应条件下，CO转化率为67.58%，高值产物选择性为70.81%[C2-4=选择性为37.74%、液体燃料（C5+）烃类选择性为33.07%]，C2-4=收率可达23.98%，副产物CO2选择性仅为5.99%。     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

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.     

2005～2006年国外塑料工业进展

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。     

2007～2008年世界塑料工业进展

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.