本文選題：水滑石 + 納米釕催化劑　； 參考：《北京化工大學(xué)》2017年碩士論文

【摘要】：鎳基催化劑在反應(yīng)過程中存在結(jié)構(gòu)坍塌,活性組分失活的現(xiàn)象,以氧化鋁為鋁源,原位生長(zhǎng)水滑石材料,在其表面負(fù)載釕納米顆粒,實(shí)現(xiàn)釕納米顆粒的高分散,用于生物質(zhì)平臺(tái)分子5-羥甲基糠醛選擇性加氫性能研究。此外,制備三元鎳銅鋁水滑石,通過焙燒和還原獲得高分散的鎳銅雙金屬催化劑用于生物質(zhì)衍生物乙酰丙酸乙酯氫轉(zhuǎn)移加氫性能研究。水滑石(LDHs)是一種二維層狀材料,因具有組成元素和比例可調(diào)變、制備方法豐富、催化活性優(yōu)異的特性而得到科研工作者們的廣泛關(guān)注。目前,在催化、光電、環(huán)境污染、阻燃、生物傳感、醫(yī)藥等方面吸引了科研人員的深入研究。本文利用原位生長(zhǎng)法制備了鎳鋁水滑石(NiAl-LDHs),利用水滑石載體的豐富孔道,通過硼氫化鈉還原法高分散負(fù)載釕納米顆粒,將制備的催化劑用于5-羥甲基糠醛選擇性加氫性能研究。此外,合成三元鎳銅鋁水滑石(NiCuAl-LDHs),焙燒還原制備鎳銅雙金屬催化劑,結(jié)構(gòu)仍能保持,將催化劑用于乙酰丙酸乙酯氫轉(zhuǎn)移加氫性能研究,進(jìn)一步分析了催化劑的結(jié)構(gòu)與活性之間的關(guān)系。(一)利用原位生長(zhǎng)法制備的NiAl-LDHs材料表面含有大量羥基,通過硼氫化鈉一步還原法將釕納米顆粒負(fù)載在NiAl-LDHs表面。經(jīng)過XRD、SEM、HRTEM、BET、XPS等表征手段,證明釕納米顆粒在載體表面均勻分散,并且與載體之間的相互作用十分強(qiáng)烈。另外,NiAl-LDHs豐富的孔道結(jié)構(gòu)和較高的比表面積,有利于實(shí)現(xiàn)貴金屬釕的高分散。特別的是,制備的Ru/NiAl催化劑能夠在以氫氣為氫源的條件下高效催化5-羥甲基糠醛生成2,5-二甲基呋喃,催化劑在重復(fù)利用五次后,催化活性沒有發(fā)生顯著降低。(二)利用原位生長(zhǎng)法制備三元鎳銅鋁水滑石(NiCuAl-LDHs)前體,經(jīng)過焙燒、還原合成高分散的鎳銅雙金屬催化劑。通過XRD、STEM、BET、TPD、FT-IR、XPS等表征手段,分析了催化劑結(jié)構(gòu)與活性之間的關(guān)系。研究結(jié)果顯示催化劑中高分散的鎳銅雙金屬納米顆粒和催化劑表面酸堿性位的協(xié)同作用,使得鎳銅雙金屬催化劑可以在常壓氮?dú)�、異丙醇作氫源的條件下(220℃ atm N2)高效催化乙酰丙酸乙酯氫轉(zhuǎn)移加氫生成γ-戊內(nèi)酯。并且,催化劑在重復(fù)利用五次后,催化活性沒有發(fā)生顯著降低。
[Abstract]:During the reaction, the structure of nickel based catalyst collapsed and the active component was deactivated. The hydrotalcite material was grown in situ with aluminum oxide as the source. The high dispersion of ruthenium nanoparticles was realized by loading ruthenium nanoparticles on the surface of the catalyst. It was used to study the selective hydrogenation of 5-hydroxymethyl furfural. In addition, ternary nickel-copper-aluminum hydrotalcite was prepared, and highly dispersed Ni-Cu bimetallic catalysts were prepared by roasting and reduction for hydrogen transfer hydrogenation of ethyl levulinate, a biomass derivative. Hydrotalcite (LDHs) is a kind of two-dimensional layered material, which is widely concerned by researchers because of its variable composition and proportion, rich preparation methods and excellent catalytic activity. At present, catalysis, photoelectricity, environmental pollution, flame retardancy, biosensor, medicine and so on have attracted more and more researchers. In this paper, Ni-Al hydrotalcite NiAl-LDHsN was prepared by in-situ growth method. The selective hydrogenation of 5-hydroxymethylfurfural was studied by using the rich pore channels of hydrotalcite carrier and highly dispersed supported ruthenium nanoparticles by sodium borohydride reduction method. In addition, the structure of Ni-Cu bimetallic catalyst prepared by the synthesis of nickel-copper-aluminum hydrotalcite, NiCuAl-LDHsN, was prepared by roasting reduction. The catalyst was used to study the hydrogen transfer hydrogenation of ethyl levulinate. The relationship between the structure and activity of the catalyst was further analyzed. (1) the surface of NiAl-LDHs prepared by in-situ growth method contains a large number of hydroxyl groups. Ruthenium nanoparticles are loaded on the surface of NiAl-LDHs by one step reduction of sodium borohydride. The results showed that ruthenium nanoparticles dispersed uniformly on the surface of the support and the interaction with the support was very strong. In addition, the rich pore structure and high specific surface area of NiAl-LDHs are conducive to the realization of high dispersion of precious metal ruthenium. In particular, the prepared Ru/NiAl catalyst can efficiently catalyze the formation of 5 hydroxymethyl furfural into 2'5 '-dimethylfuran under the condition of hydrogen as the hydrogen source, and the catalytic activity of the catalyst does not decrease significantly after being reused for five times. (2) the precursor of nickel-copper-aluminum hydrotalcite NiCuAl-LDHswas prepared by in-situ growth method and calcined to form highly dispersed Ni-Cu bimetallic catalyst. The relationship between the structure and activity of the catalyst was analyzed by means of XPS and other characterization methods. The results show that the highly dispersed Ni-Cu bimetallic nanoparticles and the acid-base sites on the surface of the catalyst make the Ni-Cu bimetallic catalyst can be used in nitrogen at atmospheric pressure. The hydrogen transfer hydrogenation of ethyl levulinate to 緯 -pentanolactone was efficiently catalyzed by isopropanol at 220 鈩，

本文編號(hào)：1957555