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1.
使用树脂为载体,合成了6种新的双铁(Ⅲ)催化剂,成功的模拟了可溶性甲烷单加氧酶(MMO)的双核铁中心.这是首次使用树脂作为载体合成模拟MMO的非均相催化剂.在室温下以乙腈为溶剂,30%的过氧化氢或特丁基过氧化氢做氧化剂,环己烷或乙苯作为底物的反应中,催化剂具有MMO相似的催化活性.其中,使用大孔氨甲基树脂为载体合成的催化剂能有效地催化乙苯氧化得到较好的转化率(总收率达69.9%,TON值达55.3).同时研究了树脂的颗粒大小及阴离子供体对催化性能的影响.使用粒径0.675~0.280 mm的树脂和ClO-4的阴离子供体所合成的催化剂具有很好的催化活性.最后探讨了催化剂的回收和再利用.  相似文献   

2.
大孔吸附树脂合成及从甜叶菊中提取分离甜菊甙的研究   总被引:4,自引:1,他引:4  
本文合成了一系列用于从甜叶菊提取液中吸附分离甜菊甙的大孔吸附树脂,测定了它们的孔结构参数及吸附量,并比较了吸附量较高的五种树脂的循环使用性能及解吸性能。实验结果表明,M-35树脂吸附量大,解吸率高,用树脂法工艺制备的甜菊甙产品纯度高,质量好。  相似文献   

3.
含酮基吸附剂对莱鲍迪甙A的吸附选择性研究   总被引:1,自引:1,他引:0  
合成了一系列具有不同骨架结构的中极性含酮基大孔吸附树脂,研究了树脂极性与骨架结构的关系,讨论了树脂对甜菊糖中两种主要糖甙甜菊甙及莱鲍迪甙A的吸附能力和吸附选择性,并设计通过树脂柱的动态色层法从甜菊甙含量高的甜菊糖中成功地分离出高莱鲍迪甙A糖产品.  相似文献   

4.
实验考察D072型阳离子交换树脂在交换柱中脱除过氧化氢中微量金属阳离子的动态行为.通过改变料液流速、高径比、料液中交换离子浓度及料液组成等参数,绘制不同条件下的透过曲线,以此考察D072型树脂对过氧化氢中金属阳离子的动态交换性能,从而确定适宜的工艺条件,为工业化生产提供科学依据.  相似文献   

5.
合成了以苯乙烯-二乙烯苯为骨架的若干叔胺型弱碱性树脂,研究了胺化反应条件,胺化试剂及交联度等对叔胺产碱树脂功能单一性的影响,测定了强碱交换量低的叔胺树脂的滴定曲线特征,找到了适合作为热再生树脂弱碱组分的单功能基叔胺树脂的合成条件。  相似文献   

6.
获得高级醇的途径主要有脂肪酸加氢法及高级酯类用金属钠还原法,因技术较复杂,所得产品的成本甚高.用羰基合成法制取高级醇的研究在国内、外曾经进行,尚不成熟.  相似文献   

7.
N263萃淋树脂的合成及其在金矿液分析中的应用   总被引:9,自引:0,他引:9  
合成了N_(263)萃淋树脂,并测定了该树脂的一些性能。用合成的N_(263)树脂分离、富集矿石中的金,在5%~20%王水介质中均可定量吸附。上柱流速2ml·min~(-1),以2.0%硫脲-1.0mol·L~(-1)盐酸作洗脱液,洗脱液流速0.5ml·L~(-1),用过氧化氢破坏硫脲后,硫代米蚩酮光度法测定金。金在10~200μg范围能定量回收,回收率达98%。方法选择性好,树脂可重复使用15次以上。  相似文献   

8.
绿色氧化剂过氧化氢   总被引:5,自引:0,他引:5  
作为氧化剂,过氧化氢反应时不产生污染产物,可称为绿色氧化剂,因而受到人们越来越多的重视。本文简述了过氧化氢化学,包括其结构、性质、氧化机理、合成工艺的发展、过氧化氢的延伸产品及其最新应用。  相似文献   

9.
高分子固载化螯合钛酸酯的合成及酯化催化性能研究   总被引:4,自引:1,他引:4  
将高分子载体聚苯乙烯二乙醇胺树脂与乙二胺钛酸二丁酯反应,制得高分子固载化螯合钛酸酯催化剂,并对其在高沸点酯的合成反应中的催化性能进行了研究,结果表明它具有良好的催化活性,易与产品酯分离,可以回收及重复使用。  相似文献   

10.
用Mitsunobu反应及丙烯酰氯酰化反应制备了用于固相有机合成的载体REM树脂,将REM树脂与苄胺加成,考查了所合成REM树脂的反应性能,并通过元素分析测定氮含量,推出REM树脂的烯丙基固载量。利用所合成的REM树脂进行了与胺、酚的加成反应动力学研究。结果表明,REM树脂与脂肪族伯胺和促胺的加成反应能够进行,与苯胺不发生反应;REM树脂与酚不能发生亲核加成反应。  相似文献   

11.
The influence of process parameters on the epoxidation of 2-buten-1-ol with 30 % hydrogen peroxide using the titanium silicalite TS-1 is presented. The studies were carried out under autogenic pressure (in autoclave). Methanol was used as a solvent in this process. The influence of temperature, 2-buten-1-ol to hydrogen peroxide mole ratio, amount of solvent used, TS-1 catalyst content, and reaction time on the reaction was studied. The major product of this reaction, 2,3-epoxybutan-1-ol (EB), has numerous applications in chemical industry.  相似文献   

12.
含氧化叔胺侧基的水溶性酚醛树脂的合成与成像性能   总被引:1,自引:0,他引:1  
本实验通过一锅、两步法制备改性酚醛树脂.首先利用环氧酚醛树脂F-44与二甲胺反应,得到叔胺化酚醛树脂,叔胺化树脂被双氧水氧化后得到最终目标产物,即含强极性氧化叔胺基团的酚醛树脂.实验表明,该新型树脂易溶于水和一些强极性溶剂,如四氢呋喃、乙二醇独甲醚和N,N-二甲基甲酰胺等.在热的作用下,树脂能够分解并失去水溶性,但仍可溶于一些有机溶剂.由该树脂与830 nm激光增感染料匹配使用,树脂体系对红外光敏感,并能够通过中性水显影得到较为清晰的阴图型图像,表明该树脂有望用于免化学处理热敏激光成像领域.  相似文献   

13.
Detection of hydrogen peroxide is of industry interest and of biological importance. Here we report a new approach to hydrogen peroxide measurement using multilayer modified microcantilevers. Through a layer-by-layer nanoassembly technique, horseradish peroxidase was intercalated into a nanoscale multilayer assembly on one surface of microcantilevers. These enzyme-functionalized microcantilevers deflected in response to hydrogen peroxide concentrations in the nanomolar level. The magnitudes of bending were proportional to the concentrations of hydrogen peroxide. Furthermore, our study also showed that microcantilever technique may be used as a novel, more sensitive tool for the study of the conformational or structural changes of enzymes or proteins on surfaces.  相似文献   

14.
A MEMS methanol reformer heated by decomposition of hydrogen peroxide   总被引:1,自引:0,他引:1  
Kim T  Hwang JS  Kwon S 《Lab on a chip》2007,7(7):835-841
This paper presents the design, fabrication and evaluation of a micro methanol reformer complete with a heat source. The micro system consists of the steam reforming reactor of methanol, the catalytic decomposition reactor of hydrogen peroxide, and a heat exchanger between the two reactors. In the present study, catalytic decomposition of hydrogen peroxide is used as a process to supply heat to the reforming reactor. The decomposition process of hydrogen peroxide produces water vapor and oxygen as a product that can be used efficiently to operate the reformer/PEMFC system. Cu/ZnO was selected as a catalyst for methanol steam reforming and Pt for the decomposition of hydrogen peroxide. Incipient wetness method was used to load catalysts on a porous support. Catalyst loaded supports were inserted in the cavity made on the glass wafer. The performance of the methanol steam reforming system was measured at various test conditions and the optimum operation condition was sought. At the optimum condition, the hydrogen selectivity was 86.4% and the thermal efficiency was 44.8%. The product gas included 74.1% H(2), 24.5% CO(2) and 1.4% CO and the total volume production rate was 23.5 ml min(-1). This amount of hydrogen can produce 1.5 W of power on a typical PEMFC.  相似文献   

15.
陈彤  付真金  祝良芳  胡常伟  田安民 《化学学报》2003,61(11):1701-1703
设计制备了Ni-Zr-Ce/Al_2O_3催化剂,研究了其上用H_2O_2直接将苯氧化胺化 合成苯胺的活性。发现在常压、50 ℃的温和条件下,该催化剂对苯、氨水与 H_2O_2直接氧化胺化生成苯胺有较好活性,并且其对苯胺的选择性远远大于对苯酚 的选择性。提高反应原料中氨水对苯的比例,能提高苯胺的收率,且不会增加苯酚 的生成量。本方法能耗低,原子利用率高,为苯胺的绿色合成提供了一条新的路径 。  相似文献   

16.
Amberlite IRA 900 anion-exchange resin modified with manganese-tetrakis(sulphophenyl)-porphine has been used as a catalyst instead of peroxidase for the determination of hydrogen peroxide by the reaction 2H(2)O(2) + N,N-diethylaniline + 4-aminoantipyrine (catalyst)--> quinonoid dye (lambda(max) 550 nm) + 4H(2)O. The apparent molar absorptivity for hydrogen peroxide was 1.1 x 10(4) 1.mole(-1).cm(-1), coefficient of variation 0.7%. This value is approximately 84% of that obtained by the use of peroxidase as catalyst. Similar conditions to those in the enzymatic reaction were suitable for use of the modified resin as catalyst, and the results show it to be a good substitute for peroxidase in this reaction system.  相似文献   

17.
A nonenzymatic method was developed for the detection and quantification of hydrogen peroxide using metallic sols obtained by the reduction of silver compounds with sodium borohydride in the presence of a surface stabilizer. These sols changed color on exposure to aqueous solutions of hydrogen peroxide. The nature of the stabilizer used in sol preparation affects spectral characteristics of the final product formed in the reaction with hydrogen peroxide. In the case of polyvinyl pyrrolidone, the intensity of the surface plasmon resosnance absorption band at 405 nm decreased. In using cetyltrimethylammonium bromide, a signal at 519 nm appeared along with the similar decrease in the absorption band at 408 nm. The band intensity depends on the concentration of hydrogen peroxide. The described phenomena can form a basis for the development of procedures for the qualitative and quantitative determination of hydrogen peroxide in water bodies.  相似文献   

18.
Mulokozi AM 《Talanta》1973,20(12):1341-1344
The interference by excess of peroxide seriously affects the reliability of chromium determination procedures involving prior oxidation of the element with sodium or hydrogen peroxide. Some of the methods used to overcome this problem are either cumbersome or unreliable. A method for quantitative and rapid isolation of chromate from alkaline peroxide solutions is now presented. This involves sorption of chromate on a strongly basic anion-exchange resin. The interfering peroxide is washed away with 2% aqueous sodium hydroxide solution.  相似文献   

19.
The influence of perchloric acid and hydrogen peroxide concentrations on the elution rates of vanadium and titanium from Dowex-50W X 8 resin was studied. The amounts of perchloric acid and of hydrogen peroxide were adjusted to provide an optimum eluent for the separation of vanadium from the irradiated titanium (TiO2) target.  相似文献   

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