本文關鍵詞： 超臨界水 苯酚 多壁碳納米管 Materials studio的模擬　出處：《昆明理工大學》2016年碩士論文　論文類型：學位論文

【摘要】：隨著人類社會的發(fā)展和社會文明的進步,人類對新型材料和可再生能源的需求越來越高。新型材料和能源的開發(fā)利用可以極大地推進世界經(jīng)濟和人類社會的發(fā)展進步。所以,研發(fā)獲得新型材料和可再生能源,一直以來都是研究學者關注的重要課題之一。本文即是在前人對納米材料碳納米管的制備和應用等研究的基礎上,在超臨界水中以碳納米管為載體,在多壁碳納米管內(nèi)部負載金屬Ru制備出了一種新型非均相催化劑用于超臨界水中苯酚的催化氣化制氫檢測其活性。其主要研究結果與結論如下：(1)超臨界水中制備多壁碳納米管內(nèi)部負載金屬Ru(Ru/MWCNTs)催化劑。通過超臨界兩步水熱合成法成功地將金屬Ru負載在了多壁碳納米管內(nèi)部,而濕浸漬法、微波多元醇合成法、溶膠凝膠法等方法只能將負載物負載在碳納米管表面。兩者相比,多壁碳納米管內(nèi)部負載金屬Ru(Ru/MWCNTs)催化劑在催化活性及選擇性方面具有更廣的應用。本文中一共選用了六種碳納米管,分別成功地將4 wt%,2 wt%及1 Wt%的金屬Ru負載在了六種碳納米管的內(nèi)部。(2)催化劑Ru/MWCNTs的活性研究：超臨界水中苯酚的催化氣化。本文中對催化劑Ru/MWCNTs進行了HR-TEM和XPS表征。HR-TEM表征結果直觀地表明,無機的金屬Ru粒子成功地負載到了多壁碳納米管的內(nèi)部。對于Ru/(60-100nm,5um) MWCNT催化劑,HR-TEM結果表明,金屬Ru粒子在60-100nm多壁碳納米管內(nèi)部均勻分布。1wt%Ru/(60-100nm,5μm) MWCNT催化劑用于超臨界水中苯酚的催化氣化,其碳轉化率甚至超過了商業(yè)催化劑(Ru/C,5wt%Ru). Ru/MWCNTs催化劑用于超臨界水中苯酚的催化氣化,可以得到70%以上的碳轉化率和100%的氣化率,是無催化劑狀態(tài)下超臨界水苯酚催化氣化的近十倍左右。有趣的是,金屬Ru粒子限制在碳納米管內(nèi)部,使超臨界水中苯酚催化氣化的產(chǎn)品C2H6和H2的生成量明顯增加。這說明,通過超臨界兩步水熱合成法制備出將金屬Ru納米顆粒密封在碳納米管內(nèi)部的催化劑呈現(xiàn)較高的催化活性和選擇性。(3) Materials Studio計算機軟件模擬催化劑Ru/MWCNTs制備的過程機理。本研究一共做了兩個模型晶胞：300個水分子的與300個水分子和6個RuCl3分子的。計算結果表明,兩個模型分子的能量隨著溫度的升高而升高,并且300個水分子和6個RuCl3分子的動能、勢能、總能高于300個水分子的。這表明,隨著溫度的升高,超臨界水的密度和分子間力降低,但分子間距離的增加,從而導致該氫鍵的數(shù)目減小,并且溶質(zhì)擴散阻力變?nèi)酢亩贸鼋Y論,在低溫時,RuCl3溶液分子在水中擴散并且均勻分布,隨著溫度的迅速升到380℃達到超臨界狀態(tài),RuCl3溶液分子快速沉降,分子間的距離增加,導致RuCl32溶液分子不溶于水,使停留在碳納米管中間的缺陷部分及兩端的RuCl3溶液分子進入到碳納米管內(nèi)部。
[Abstract]:With the development of human society and the progress of social civilization. Human demand for new materials and renewable energy is increasing. The development and utilization of new materials and energy can greatly promote the development and progress of the world economy and human society. Research and development of new materials and renewable energy has been one of the most important research topics. This paper is based on the previous research on the preparation and application of carbon nanotubes (CNTs). Carbon nanotubes were used as carriers in supercritical water. A novel heterogeneous catalyst was prepared in the presence of metal Ru in multi-walled carbon nanotubes (MCNTs) for catalytic gasification of phenol in supercritical water to detect its activity. The main results and conclusions are as follows: 1). RuRu-MWCNTssupported metal catalysts were prepared in supercritical water. Metal Ru was successfully loaded in multi-walled carbon nanotubes by supercritical two-step hydrothermal synthesis. However, wet-impregnation method, microwave polyol synthesis method, sol-gel method and other methods can only load the support on the surface of carbon nanotubes. There are six kinds of carbon nanotubes (CNTs) in this paper, which have been widely used in the catalytic activity and selectivity of the multi-walled carbon nanotubes (MwCNTs) supported by metal Ruo / Ru-MWCNTs. in this paper, there are six kinds of carbon nanotubes. 4 wt% was successfully obtained respectively. 2wt% and 1Wt% metal Ru loaded on the inner of six carbon nanotubes. Study on the activity of Ru/MWCNTs catalyst:. Catalytic gasification of phenol in supercritical water. In this paper, HR-TEM and XPS characterization of the catalyst Ru/MWCNTs. HR-TEM characterization results show intuitively. Inorganic metal Ru particles were successfully loaded into the multi-walled carbon nanotubes (MCNTs). HR-TEM results showed that the Ru particles were successfully loaded into the multi-walled carbon nanotubes (MCNTs). The metal Ru particles are uniformly distributed in 60-100 nm multi-walled carbon nanotubes. 5 渭 m) MWCNT catalyst was used to catalyze the gasification of phenol in supercritical water, and its carbon conversion was even higher than that of commercial catalyst Rup / C. The catalytic gasification of phenol in supercritical water with Ru/MWCNTs catalyst for 5 wtt can yield more than 70% carbon conversion and 100% gasification rate. It is about ten times higher than the catalytic gasification of phenol in supercritical water without catalyst. Interestingly, the metal Ru particles are confined to the carbon nanotubes (CNTs). The production of C _ 2H _ 6 and H _ 2 in the products of phenol catalytic gasification in supercritical water was obviously increased. The catalysts sealed by metal Ru nanoparticles inside carbon nanotubes were prepared by supercritical two-step hydrothermal synthesis. The catalysts showed high catalytic activity and selectivity. The Materials Studio computer software was used to simulate the process mechanism of the preparation of catalyst Ru/MWCNTs. In this study, two model cells were made. Of 300 water molecules and 300 water molecules and 6 RuCl3 molecules. The energy of the two model molecules increases with the increase of temperature, and the kinetic energy and potential energy of 300 water molecules and 6 RuCl3 molecules are always higher than that of 300 water molecules. With the increase of temperature, the density and intermolecular force of supercritical water decrease, but the distance between molecules increases, which results in the decrease of the number of hydrogen bonds and the weakening of solute diffusion resistance. The molecules of RuCl3 solution diffuse and distribute uniformly in water. With the rapid rise of temperature to 380 鈩，

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