首页 | 官方网站   微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
以阜新天然沸石为原料,利用X射线荧光光谱仪(XRF)、红外光谱(IR)、差热(DT)对其进行分析.研究了焙烧改性、酸改性、碱改性、盐改性和有机改性等方法对沸石除氟效果的影响,并对改性沸石的除氟机理进行了探讨.结果表明:采用450℃焙烧4h,1.0 mol/L氢氧化钠浸泡24h,1.5 mol/L硫酸铝钾浸泡36 h的方法复合改性沸石,沸石粒度为40 ~ 60目,静态除氟固液比为5∶100(g∶mL),可使10 mg/L的模拟废水氟离子浓度降低到1.0 mg/L以下,达到国家饮用水含氟标准.  相似文献   

2.
研究应用酸碱处理,硫酸铁浸泡等方法来改性天然沸石,探讨其除氟性能,并得到了最佳的改性途径:40~80目斜发沸石用去离子水冲洗、烘干,然后在1.38 mol/L硫酸溶液中搅拌、浸泡24 h,洗净烘干,最后在Fe~(3+)浓度为1.5 mol/L的硫酸铁溶液中煮沸、搅拌2 h.采用静态和动态相结合的方法确定了影响沸石除氟的多种因素,并对除氟过程的吸附模式、热力学性质进行了研究.  相似文献   

3.
改性沸石去除中低放废水中痕量放射性核素的研究   总被引:1,自引:0,他引:1  
研究了天然沸石的改性及其去除模拟中低放废水中痕量放射性核素的性能.将预处理好的天然沸石在浓度为0.25 mol/L的NaCl溶液中浸泡并在25℃、转速为200 r/min下恒温振荡24h,洗净烘干后得到钠型改性沸石.研究了吸附时间、溶液pH、沸石投加量和竞争离子对沸石吸附Co2+的影响,得到了最佳吸附条件:Co2+起始...  相似文献   

4.
游新国  张晓宁 《辽宁化工》2011,40(3):221-224,229
以不同方法制备Al改性沸石,对氟过量饮用水进行吸附试验,考察其处理效果。试验结果显示,不同改性沸石对含氟水的吸附效果有差异,其中复合Al改性沸石的吸附效果最好,在以3.00 mol/L盐酸浸泡10 h,0.20 mol/L硫酸铝浸泡7 h的最优制备条件下,复合Al改性沸石对初始F-离子浓度1.63 mg/L的含氟水的去除率可达45.21%,出水F-离子浓度为0.893 mg/L。且复合Al改性沸石对高浓度含氟水也有较好的吸附效果。研究结果表明,复合Al改性沸石制备方法可行,常规含氟地下水源水经其吸附处理后含氟量在1.00 mg/L以下,可达到国家生活饮用水卫生标准。  相似文献   

5.
苏少龙  刘建 《应用化工》2013,(2):205-209
以沸石分子筛为骨架原料,通过在不同类型的铝盐溶液中交换吸附,使分子筛载铝,获得了具有配体交换结合氟性能的改性分子筛,研究了不同类型分子筛载铝改性条件及改性分子筛除氟性能。结果表明,用硝酸铝溶液改性各分子筛效果最好,而用其改性的各分子筛中,改性5A分子筛除氟效果显著,对于氟的静态饱和吸附量为29.940 1 mg/g,且不易受pH和多种共存离子的影响。改性5A分子筛的最佳除氟条件:温度40℃,吸附时间100 min,反应物物料配比为0.03~0.05 g/L氟溶液(氟离子浓度为10 mg/L)。流动除氟实验表明,利用改性5A分子筛除氟可把氟离子浓度降低到小于1 mg/L,达到国家饮水标准。  相似文献   

6.
对天然沸石和Fe Cl3改性沸石的物化特性进行表征,并研究其对磷酸盐的吸附效能和机理。结果表明:改性后沸石的晶体形貌、表面性能和化学成分发生变化。在粒径为0.3~0.6 mm、投加量为50 g/L、磷酸盐初始质量浓度为50 mg/L、温度为25℃、p H=7、吸附时间为10 h的条件下,天然沸石和改性沸石对磷酸盐的去除率分别为24.3%、98.45%。改性沸石的再生能力较强。Freundlich、热力学模型和再生实验结果表明改性沸石对磷酸盐的吸附以物理吸附为主。  相似文献   

7.
采用氯化钠离子交换和氯氧化锆沉积-沉淀两步法改性天然沸石,得到具有脱除水中氨氮和磷的双功能锆钠改性天然沸石(Zr-Na/Zeolite)。考察了Zr-Na/Zeolite在不同pH、氨氮和磷初始质量浓度和温度下对氨氮溶液、含磷溶液及氮磷共存溶液的吸附情况。结果表明,Zr-Na/Zeolite能够在保持Na改性沸石(Na/Zeolite)优良的吸附氨氮性能的基础上,极大地提高吸附磷的能力。在不同pH下,Zr-Na/Zeolite吸附氨氮和磷的效果呈现不同的规律。对于氨氮,水溶液pH在4~8时Zr-Na/Zeolite具有最佳吸附性能,最高吸附量达到4.5 mg/g。对于含磷阴离子,脱磷能力随pH的升高而降低,吸附量从pH=2时的4.71 mg/g降到pH=10时的2.20 mg/g。当Zr-Na/Zeolite投加量为0.2 g,氨氮和磷初始质量浓度从10 mg/L提高到200 mg/L时,氨氮和磷的吸附量分别从1.42和2.46 mg/g提高到11.60和11.80 mg/g。溶液温度从25℃升高到45℃时,氨氮的吸附量提高了10%,磷的吸附量提高了11%。磷和氨氮的吸附过程符合准二级动力学模型。0.1 mol/L Na OH和1.0 mol/L Na Cl混合溶液可以再生Zr-Na/Zeolite,循环吸附14次后,吸附效率几乎保持不变。  相似文献   

8.
改性沸石除氟的动态实验研究   总被引:1,自引:0,他引:1  
为将阴离子型改性沸石应用于实际,通过动态吸附实验,对用改性沸石除氟技术的可行性进行了研究。实验对影响除氟的pH、水力停留时间、溶液中可能共存的阴离子竞争影响、前水的氟浓度的几个主要的因素水平进行了实验分析。得出在原水pH为7.7、水力停留时间为80 min、氟离子浓度为5 mg/L时改性沸石除氟动态平衡吸附量最佳。溶液中的阴离子SO42-对除氟效果影响较大  相似文献   

9.
采用氯化钠离子交换和氯氧化锆沉积沉淀两步法改性天然沸石,得到具有脱除水中氨氮和磷的双功能锆钠改性天然沸石(Zr-Na/Zeolite),考察了不同pH、溶液初始质量浓度和温度下Zr-Na/Zeolite对氨氮溶液、含磷溶液及氮磷共存溶液的吸附情况。结果表明,Zr-Na/Zeolite能够在保持Na改性沸石(Na/Zeolite)优良的吸附氨氮性能的基础上,极大地提高吸附磷的能力。在不同pH下,Zr-Na/Zeolite 吸附氨氮和磷的效果呈现不同的规律。对于氨氮,水溶液pH在4~8时具有最佳吸附性能,最高吸附量达到4.5 mg/g。对于含磷阴离子,脱磷能力随pH的升高而降低,吸附容量从pH=2时的4.71 mg/g降到pH=10时的2.20 mg/g。溶液初始质量浓度从10 mg/L提高到200 mg/L时,氨氮和磷的单位吸附容量分别从1.42和2.46 mg/g提高到11.6和11.8 mg/g,去除率分别从57.0%和98.2%降低到23.2%和23.6%。溶液温度从25 ℃升高到45 ℃,氨氮的吸附容量提高了10%,磷的吸附容量提高了11%。磷和氨氮的吸附过程符合准二级动力学模型。0.1 mol/L NaOH和1.0 mol/L NaCl混合溶液可以再生Zr-Na/Zeolite,循环吸附14次,吸附效率几乎保持不变。  相似文献   

10.
为提高沸石对氨氮废水的处理能力,对沸石进行了优化改性,探讨了改性剂种类、改性剂浓度和不同改性操作方法对沸石去除氨氮的影响。结果表明,经氢氧化钠和氯化钠溶液改性的沸石,其氨氮去除性能有明显提升,而磷酸处理后的沸石对氨氮的去除无明显作用,且加热搅拌对沸石改性的效果优于混合静置的方法。采用1.5 mol/L的氢氧化钠溶液浸渍沸石、搅拌加热1 h后,可获得最佳的改性沸石,强化的离子交换作用使得沸石对水中的氨氮有良好的去除效果。室温下,在初始氨氮浓度为50 mg/L的溶液中投加4 g/L的改性沸石,反应2 h后,氨氮的去除率可达90%,且反应后溶液的pH变为弱碱性,更利于氨氮的析出。耗竭的沸石用0.9 mol/L的氯化钠溶液进行解吸并再生,经3次解吸和再生后,沸石的解吸率为86.3%,吸附容量约为原沸石的70%。  相似文献   

11.
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   

12.
13.
14.
15.
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   

16.
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   

17.
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   

18.
Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

19.
20.
Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号