Interface synergy between IrOx and H-ZSM-5 in selective C–O hydrogenolysis of glycerol toward 1,3-propanediol
作者:Xiaoyue Wan、Qi Zhang、Mingming Zhu、Yi Zhao、Yongmei Liu、Chunmei Zhou、Yanhui Yang、Yong Cao
DOI:10.1016/j.jcat.2019.06.025
日期:2019.7
of glycerol toward 1,3-PDO in the absence of acid additives. The results revealed the necessity to control the Ir domain dispersions, Ir0/Ir3+ ratio and the amounts of overall acid/Brönsted acid sites. Activity depended linearly on the amount of overall and Brönsted acid sites, and 1,3-PDO selectivity increased in the presence of Ir-induced Brönsted acid sites, denoted as Ir-O(H)-H-ZSM-5. We speculate
羟基的位点选择性脱氧代表了获得具有工业潜力的有价值的功能化生物基化合物的基本过程。在这种情况下,具有挑战性的任务之一是在大量水存在下将生物柴油衍生的甘油直接转化为新兴的聚合物工业的关键组成部分1,3-丙二醇(1,3-PDO)。本文中,通过研磨辅助浸渍程序制备了在不存在亲氧金属氧化物的情况下负载在H-ZSM-5上的单金属铱,并尝试将其作为有效的可循环催化剂,用于甘油在水相中选择性地氢解成1,3-羟基。在没有酸添加剂的PDO中。结果表明控制Ir域分散度Ir 0 / Ir 3+的必要性比例和总酸/布朗斯台德酸位的数量。活性线性地取决于总酸位和布朗斯台德酸位点的数量,在Ir诱导的布朗斯台德酸位点存在下,以Ir-O(H)-H-ZSM-5表示的1,3-PDO选择性增加。我们推测的IrO(H)-H-ZSM-5通过的IrO之间的界面协同相互作用产生X和H-ZSM-5通过氢溢出和反向氢溢出根据文献报道。基于
Oxidation of alkanes
申请人:Holtcamp W. Matthew
公开号:US20060293539A1
公开(公告)日:2006-12-28
Alkanes are oxidised to oxygenates such as carboxylic acids with molecular oxygen employing a two component catalyst system which uses a liganded heavy metal compound and a mixed metal oxide.
烷烃通过使用含有配体的重金属化合物和混合金属氧化物的双组分催化剂系统,被氧化为羧酸等含氧化合物。
Dual modification of TiNb<sub>2</sub>O<sub>7</sub> with nitrogen dopants and oxygen vacancies for selective aerobic oxidation of benzylamine to imine under green light
作者:Zhuobin Yu、Eric R. Waclawik、Zhijian Wang、Xianmo Gu、Yong Yuan、Zhanfeng Zheng
DOI:10.1039/c6ta11061d
日期:——
orbital band above the O 2p valence band and oxygen vacancy (Vo) levels were formed by the ethanol treatment. The photocatalytic performance of modified Vo–N–TiNb2O7 towards selectiveaerobicoxidation reactions under green light (475–600 nm, peaked at 525 nm) was measured. It exhibits a high conversion of benzylamine (above 90%) at 80 °C over 24 h with selectivity for N-benzylidenebenzylamine greater than
通过简单的水热法和随后的热处理制备TiNb 2 O 7粉末。V ø -N-的TiNb 2 ö 7用NH生成3和乙醇双重治疗。NH 3处理在O 2p价带上方产生了一个新的N 2p轨道带,并且通过乙醇处理形成了氧空位(V o)水平。改性的V o –N–TiNb 2 O 7的光催化性能测量了在绿光(475–600 nm,峰值在525 nm)下对选择性好氧氧化反应的影响。它在80°C的条件下在24小时内显示出高的苄胺转化率(超过90%),在绿灯下对N-亚苄基苄胺的选择性大于95%,这比未改性和单改性的TiNb 2 O 7更好。建议双重修饰改变TiNb 2 O 7的电子能带结构并导致更窄的带隙,这应该是增强的光催化活性的原因。
Mixed metal oxide catalysts and processes for their preparation and use
申请人:Wang Kun
公开号:US20080161602A1
公开(公告)日:2008-07-03
A catalyst for the oxidation of an alkane, alkene or mixtures thereof. The catalyst includes a mixed-metal oxide having the formula Mo
a
V
b
Nb
c
Te
d
Sb
e
O
f
wherein, when a=1, b=0.01 to 1.0, c=0.01 to 1.0, d=0.01 to 1.0, e=0.01 to 1.0, and f is dependent upon the oxidation state of the other elements, the catalyst further characterized by having at least two crystal phases, the first crystal phase being an orthorhombic M1 phase and the second crystal phase being a pseudo-hexagonal M2 phase, the orthorhombic M1 phase present in an amount between greater than 60 weight percent to less than 90 weight percent. The catalysts disclosed herein exhibit a chemisorption of NH
3
of less than about 0.2 mmole per gram of metal oxide.
Efficient synthesis of niobium pentoxide nanowires and application in ethanolysis of furfuryl alcohol
作者:Zhenwei Zhang、Peng Wang、Zeying Wu、Chuanjun Yue、Xuejiao Wei、Jiwei Zheng、Mei Xiang、Baoliang Liu
DOI:10.1039/d0ra00085j
日期:——
Nb2O5 nanowires with high specific surface area and crystallinity were prepared by using ammonium oxalate and an acetic acid solvent system. The nanomaterial was applied in ethanolysis of furfuryl alcohol (FA), and the yield of the product, 2-(ethoxymethyl)furan (FEE), achieved was up to 79.6%. Compared to mesoporous Nb2O5 materials and other porous materials, the residence time of FEE on the surface
采用草酸铵和乙酸溶剂体系制备了具有高比表面积和结晶度的Nb 2 O 5纳米线。该纳米材料应用于糠醇(FA)的乙醇分解,产物2-(乙氧基甲基)呋喃(FEE)的收率高达79.6%。与介孔Nb 2 O 5材料和其他多孔材料相比,FEE在催化剂表面的停留时间较短,乙酰丙酸乙酯(EL)的产率较低。此外,高温煅烧处理可以改变纳米线表面的酸位和酸度类型分布。通过XRD、NH 3 -TPD、IR、TG-DTA测定方法发现,经过300 ℃处理后,Nb 2 O 5纳米线表面的弱酸位和中强酸位减少,且酸位减少。强酸含量相对较高。根据催化性能测试数据和酸度测定,得出结论:更多的弱酸和中强酸位点促进了糠醇向FEE的转化,强酸位点促进FEE进一步转化为EL。