本文關(guān)鍵詞： 鉬硫簇合物 鉬氧硫簇合物 多孔分子篩 負(fù)載 加氫脫硫　出處：《安徽工業(yè)大學(xué)》2016年碩士論文　論文類型：學(xué)位論文

【摘要】：多核鉬硫簇的特殊結(jié)構(gòu)使其具有豐富的活性硫原子,如穩(wěn)定的橋硫原子和活性相對較高的端硫原子,從而使得多核鉬硫簇合物在加氫脫硫和電化學(xué)析氫等方面具有廣泛的應(yīng)用。本論文中共制備了5個多核鉬硫簇合物((Et4N)2[Mo3S9]、(HNEt3)2[Mo3S7(mba)3]、(NH4)2[Mo3S13]·nH2O、(NH4)2[Mo2S12]·2H2O、(Et4N)2[Mo2S10])和6個多核鉬氧硫簇合物((Me4N)2[Mo2S6O2]、Cs2[Mo4S4O4(C4O6)2]、(Me4N)4[Mo6S14O6]、K3(Me4N)[Mo6S6O6(OH)4(C2O4)3]、Cs2[Mo8S8O8(OH)10]、(Me4N)[Mo9S8O12])。為了避免均相催化中存在的穩(wěn)定性差,重復(fù)利用率低以及難回收等問題,采用浸漬法將上述多核鉬硫簇合物和鉬氧硫簇合物負(fù)載到分子篩SBA-15上得到負(fù)載型催化劑。通過紅外光譜(IR)、X-射線衍射(XRD)、透射電鏡(TEM)等方法對負(fù)載型催化劑的結(jié)構(gòu)進(jìn)行表征和分析。結(jié)果表明:兩種系列負(fù)載催化劑都很好地保持了分子篩的介孔結(jié)構(gòu)性質(zhì),多核鉬硫簇合物和鉬氧硫簇合物均勻地分散在分子篩SBA-15上。以噻吩作為催化底物,系統(tǒng)地考查了系列負(fù)載型多核鉬硫簇合物催化劑在不同條件下的加氫脫硫催化效果。結(jié)果表明:在280℃、18小時、1.0 MPa氫氣壓力下兩類負(fù)載型催化劑能夠表現(xiàn)出較好的催化效果,而且具有較好的多次循環(huán)的綠色催化效果,其中硫單元S22-個數(shù)較多的簇合物(NH4)2[Mo3S13]·nH2O、(NH4)2[Mo2S12]·2H2O和(Me4N)4Mo6S14O6表現(xiàn)出相對較好的催化效果。機(jī)理分析表明:多核鉬硫簇合物中S22-單元對加氫脫硫反應(yīng)的催化活性具有促進(jìn)作用,硫單元S22-在氫氣作用下生成高活性的加氫基團(tuán)-SH,氫原子從-SH基團(tuán)上轉(zhuǎn)移到噻吩的碳原子上生成四氫噻吩,完成加氫過程。簇合物上的S在氫氣作用下以H2S的形式脫去產(chǎn)生空位,與此同時四氫噻吩上的硫進(jìn)攻此空位并與Mo結(jié)合完成脫硫的步驟。
[Abstract]:The special structure of the polynuclear molybdenum sulfur cluster makes it rich in active sulfur atoms, such as stable bridged sulfur atoms and relatively high active terminal sulfur atoms. Therefore, the polynuclear molybdenum sulfur cluster has been widely used in hydrodesulfurization and electrochemical hydrogen evolution. [Mo3S9. [Mo3S7(mba)3. [Mo3S13] 路NH _ 4H _ 2O _ 2. [Mo2S12] 路2H _ 2O _ 4N _ 2. [(Mo2S10) and 6 polynuclear molybdenum oxysulfide clusters. [Mo2S6O2] ,Cs2. [Mo4S4O4(C4O6)2. [Mo6S14O6). [Mo6S6O6(OH)4(C2O4)3] ,Cs2. [Mo8S8O8(OH)10 (Me4N). [In order to avoid the problems of poor stability, low reuse rate and difficult recovery in homogeneous catalysis, Mo9S8O12]. The polynuclear molybdenum sulfur cluster and molybdenum oxide sulfur cluster were loaded on the molecular sieve SBA-15 by impregnation method to obtain the supported catalyst. The structure of the supported catalyst was characterized and analyzed by TEM and TEM. The results showed that the mesoporous structure of the molecular sieve was well maintained by the two series of supported catalysts. The polynuclear molybdenum sulfur cluster and the molybdenum oxide sulfur cluster were uniformly dispersed on the molecular sieve SBA-15 with thiophene as the catalyst substrate. The catalytic effects of a series of supported polynuclear molybdenum sulfur cluster catalysts on hydrodesulfurization under different conditions were systematically investigated. The results showed that the catalyst was at 280 鈩，

本文編號：1451181