国产bbaaaaa片,成年美女黄网站色视频免费,成年黄大片,а天堂中文最新一区二区三区,成人精品视频一区二区三区尤物

首頁> 外文學(xué)位 >Oligomerization of methane to higher hydrocarbons using microwave heating and microwave plasmas.
【24h】

Oligomerization of methane to higher hydrocarbons using microwave heating and microwave plasmas.

機(jī)譯：使用微波加熱和微波等離子體將甲烷低聚為高級(jí)烴。

獲取原文
獲取原文并翻譯 | 示例
  • 摘要
  • 著錄項(xiàng)
  • 相似文獻(xiàn)
  • 相關(guān)主題

摘要

Catalytic microwave heating and microwave plasmas processes have been used as for the oligomerization of methane to higher hydrocarbons.; Microwave-Induced Oligomerization (MIO) of methane to higher hydrocarbons has been the focus of very few fundamental studies. Our primary goal was to understand what factors control such MIO processes, and their effect on catalysts activities and product distribution. Optimization of reactor types, modes of operation (contact times, pulse vs. continuous), catalyst pretreatment, and addition of dielectrics have been used to optimize conversion and selectivity. Product analyses by gas chromatography mass spectrometry methods, and catalysts characterization by TPR, TPD, BET, XPS and XRD studies before and after reaction. The microwave heating oligomerization experiments have shown that nickel, iron powder, and activated carbon can act as selective catalysts for oligomerized products of methane. Oligomers ranging from C2 to C6 hydrocarbons (benzene) have been prepared in good selectivity depending on the nature of diluent, type of catalyst, catalyst pretreatment and the power levels used in the microwave reactor. The use of He as diluent gas favors the oligomerization of methane via microwave heating. Data suggest that the dielectric constant is not the most important factor in the oligomerzation of methane via microwave heating. Conversion and activities of materials we used were not proportionally related to the surface area of the catalysts. Changes in catalysts structure, composition, morphology, particle size, surface area, before and after reaction, were correlated with catalysts activity and procust distribution. Microwave plasmas were used to activate C-H bonds in methane molecules. The major products observed in these earlier reactions are C2H2, C2H4, and C2H 6. We examined the effect of pressure (1--50 Torr), flow rate, and applied power (0--120 W), presence of dielectric materials, type of cavity (Beenakker or Evenson), cavities in series or in parallel, expansion and compression effects, as well as the presence of a radical initiator (I 2, in this case) on the product distribution of methane oligomerization via microwave plasmas. The Beenakker cavity is more efficient than the Evenson cavity. The Beenakker cavity with or without He favors the formation of C 4S when using C2H4 and C2H2 as a feed. The Evenson cavity favors the formation of C4S and C 6S when using ethylene as a feed and the formation of C7S and C8S when using acetylene. (Abstract shortened by UMI.)
機(jī)譯：催化微波加熱和微波等離子體工藝已用于將甲烷低聚為高級(jí)烴。微波誘導(dǎo)甲烷向低級(jí)烴的低聚反應(yīng)（MIO）一直是很少的基礎(chǔ)研究的重點(diǎn)。我們的主要目標(biāo)是了解哪些因素控制了這種MIO工藝及其對(duì)催化劑活性和產(chǎn)物分布的影響。反應(yīng)器類型，操作模式（接觸時(shí)間，脈沖與連續(xù)），催化劑預(yù)處理和電介質(zhì)添加的優(yōu)化已用于優(yōu)化轉(zhuǎn)化率和選擇性。反應(yīng)前后通過氣相色譜質(zhì)譜法進(jìn)行產(chǎn)物分析，并通過TPR，TPD，BET，XPS和XRD研究對(duì)催化劑進(jìn)行表征。微波加熱低聚實(shí)驗(yàn)表明，鎳，鐵粉和活性炭可以作為甲烷低聚產(chǎn)物的選擇性催化劑。已經(jīng)根據(jù)稀釋劑的性質(zhì)，催化劑的類型，催化劑的預(yù)處理以及微波反應(yīng)器中使用的功率水平，以良好的選擇性制備了從C 2至C 6的烴（苯）的低聚物。使用He作為稀釋氣體有助于通過微波加熱使甲烷低聚。數(shù)據(jù)表明介電常數(shù)不是通過微波加熱甲烷低聚的最重要因素。我們使用的材料的轉(zhuǎn)化率和活性與催化劑的表面積沒有成比例的關(guān)系。反應(yīng)前后催化劑結(jié)構(gòu)，組成，形態(tài)，粒徑，表面積的變化與催化劑活性和過程分布有關(guān)。微波等離子體用于激活甲烷分子中的C-H鍵。在這些較早的反應(yīng)中觀察到的主要產(chǎn)物是C2H2，C2H4和C2H6。我們研究了壓力（1--50 Torr），流速和施加功率（0--120 W），介電材料的存在，腔的類型（Beenakker或Evenson），串聯(lián)或并聯(lián)的腔，膨脹和壓縮效應(yīng)，以及自由基引發(fā)劑（在這種情況下為I 2）的存在，通過微波等離子體在甲烷低聚產(chǎn)物分布中發(fā)揮作用。 Beenakker腔比Evenson腔更有效。當(dāng)使用C2H4和C2H2作為進(jìn)料時(shí)，有或沒有He的Beenakker腔都有利于C 4S的形成。當(dāng)使用乙烯作為進(jìn)料時(shí)，Evenson腔有利于C4S和C 6S的形成，而使用乙炔時(shí)則有利于C7S和C8S的形成。 （摘要由UMI縮短。）

著錄項(xiàng)

相似文獻(xiàn)

  • 外文文獻(xiàn)
  • 中文文獻(xiàn)
  • 專利
獲取原文

客服郵箱：kefu@zhangqiaokeyan.com

京公網(wǎng)安備：11010802029741號(hào) ICP備案號(hào)：京ICP備15016152號(hào)-6 六維聯(lián)合信息科技 (北京) 有限公司?版權(quán)所有

  • 客服微信

  • 服務(wù)號(hào)