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1.
将酸碱盐改性的TS-1分子筛用于甲乙酮(MEK)氨氧化反应中,考察了改性物质、反应温度、原料摩尔比、催化剂用量和后续反应时间对反应的影响及催化剂的重复使用与再生性能.结果表明: Zn(NO3)2改性的TS-1为适宜催化剂,较优的工艺条件是反应温度为70 ℃,n(NH3)∶ n(MEK)∶ n(H2O2)=3.5∶ 1∶...  相似文献   

2.
ZrO2-MnO2-ZnO supports were prepared by the co-precipitation method,and then Ni-Na/ZrO2-MnO2-ZnO catalysts were prepared by the impregnation method.In this paper,the reactions to synthesize methyl isopropyl ketone and diethyl ketone by the one-step synthesis method over this catalyst were studied,and meanwhile,the impact of the catalyst preparation conditions and the reaction conditions on catalyst performance was also investigated.It was observed that under the conditions when Ni loading was 25%,calcination temperature was 400℃ and reduction temperature was 410℃,this catalyst had good catalytic performance on the reaction.The suitable reaction conditions were achieved:reaction temperature was 400℃;reaction at atmospheric pressure;liquid hourly space velocity of raw material of 0.5 h 1 ;and the molar ratio of(methanol)/(methyl ethyl ketone)/(water) was equal to 1/1/1.Under such conditions,the conversion of methyl ethyl ketone could achieve 41.7%,and the overall selectivity of methyl isopropyl ketone and diethyl ketone could achieve 83.3%,which was comparable to the conversion of 38.1% and the selectivity of 82.2% achieved by using palladium as the active material.The good stability made this catalyst have good prospects for industrial application.  相似文献   

3.
吴建一  马金兴 《化学世界》2001,42(9):477-479
在相转移催化剂的作用下 ,2 -丁酮由 3 0 %的双氧水氧化制取过氧化甲乙酮。通过正交试验和考察原料配比、反应温度、相转移催化剂用量、反应时间对产品质量的影响 ,确定了最佳工艺条件为 n双氧水 ∶n丁酮 =1 .5∶ 1 ,相转移催化剂采用三乙基苄基氯化铵 ,用量占总质量的 0 .4% ,在氨基磺酸的催化下 ,反应温度 5℃左右 ,反应时间 3 0 min,稀释剂用邻苯二甲酸二丁酯 ,产品经测定 ,对不饱和聚酯的凝胶时间适宜并稳定 ,产品活性氧含量高。  相似文献   

4.
Combustion of dilute toluene and methyl ethyl ketone over Mn‐doped ZrO2 catalysts prepared using different precipitating agents, such as tetra‐alkyl ammonium hydroxides and NH4OH, having Mn/Zr ratios from 0.05 to 0.67, and calcined at different temperatures has been thoroughly investigated. The Mn‐doped ZrO2 catalyst shows high toluene or methyl ethyl ketone combustion activity, particularly when its ZrO2 is in cubic form, when its Mn/Zr ratio is close to 0.2, and when it is prepared using tetra‐methyl ammonium hydroxide as a precipitating agent and calcined at 773 K. Copyright © 2005 Society of Chemical Industry  相似文献   

5.
丁酮肟由于其低毒、低污染和高脱氧效果而被用作防结皮剂、锅炉的除氧剂和脱酮肟基硅烷交联剂的生产原料,然而丁酮肟及其二元混合体系的密度与黏度却鲜有报道。本文利用密度瓶,测定了丁酮肟-丁酮、丁酮肟-环己烷和丁酮肟-正己烷三个二元体系在(293.15~303.15)K、常压条件下的密度,用乌氏黏度计测定了三个二元混合体系在(293.15~303.15)K、常压条件下的黏度。对不同温度下混合密度与组成的关系,通过多项式方程进行了拟合;对不同温度下混合黏度与组成的关系,分别通过Grunberg-Nissan和Eyring-UNIQUAC方程进行了拟合,并给出了回归系数和平均相对偏差。本文数据和关联可为丁酮肟相关工业过程的设计、模拟和优化提供便利。  相似文献   

6.
以煤基乙酸下游产品乙酸甲酯为原料, 在Cu-Zn-Al催化剂上加氢制取乙醇, 利用气相色谱仪对产品进行定性、定量分析。分别考察了反应温度、反应压力、乙酸甲酯液时空速、氢气与乙酸甲酯摩尔比等操作因素对乙酸甲酯转化率和目标产物乙醇选择性的影响。实验结果表明, 最佳工艺操作参数为:反应温度240℃, 反应压力8MPa, 乙酸甲酯液相体积空速1h-1, 氢气与乙酸甲酯的摩尔比9:1。在最优工艺条件下, 乙酸甲酯的单程转化率为95.5%, 目的产物乙醇的选择性为94.6%。液体产品的平衡组成为:甲醇38.12%, 乙醇59.52%, 乙酸甲酯0.86%, 乙酸乙酯1.29%。数据表明:在乙酸甲酯加氢制乙醇反应过程中, Cu-Zn-Al催化剂对羰基加氢的活性较高, 对乙醇具有较高的选择性, 同时能够有效抑制主要副产物乙酸乙酯的生成。  相似文献   

7.
在小型装置上,采用M-3催化剂,对丙酮加氢合成MIBK的工艺条件进行了研究。考察了反应温度、压力、空速对反应的影响,确定了适合于该反应的最佳条件。并对M-3催化剂进行了7 200 h寿命试验。结果表明,寿命试验全程丙酮平均转化率为30.68%,MIBK选择性为94.71%。M-3催化剂具有耐温性能好、温度使用范围宽、催化活性高、使用寿命长的优点。  相似文献   

8.
Epoxidized methyl acetoricinoleate (EMAR) was generated by epoxidation of methyl acetoricinoleate (MAR) in the presence of formic acid and hydrogen peroxide by using ionic liquids as catalysts, and the product was characterized by means of infrared spectroscopy and mass spectrometry. The efficiencies of four different catalysts, 1‐methylimidazole hydrogen sulfate salt ([Hmim]HSO4), 1‐methylpyrrolidone hydrogen sulfate salt ([Hnmp]HSO4), phosphoric acid, and sulfuric acid, were compared. The effects of the formic acid/MAR molar ratio, hydrogen peroxide/MAR molar ratio, reaction temperature, reaction time, and catalyst dosage on the epoxy value of EMAR were investigated by single‐factor experiments.  相似文献   

9.
Methyl methacrylate (MMA) was successfully grafted onto rubber‐wood fiber in a free‐radical solution polymerization initiated by ferrous ion and hydrogen peroxide. The effects of the reaction parameters (reaction temperature, reaction period, influence of hydrogen peroxide, ferrous ammonium sulfate, and monomer concentrations) were investigated. The grafting percentage showed dependency on H2O2, Fe2+, and monomer concentrations, as well as reaction temperature and reaction period. The optimum reaction temperature was determined to be about 60°C and the reaction period was 60 min. The optimum concentration of H2O2 was 0.03M and optimum amounts of Fe2+ and MMA were 0.26 mmol and 2.36 × 10?2 mol, respectively. Poly(methyl methacrylate) (PMMA) homopolymer was removed from the graft copolymer by Soxhlet extractor using acetone. The presence of PMMA on the fiber was shown by FT‐IR spectroscopy and gravimetric analysis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2499–2503, 2003  相似文献   

10.
使用甲乙酮肟和苯酚分别对聚醚型聚氨酯预聚体进行封端,然后与端氨基非异氰酸酯基聚氨酯预聚体嵌段扩链,制备聚氨酯膜。分析了甲乙酮肟和苯酚的封端温度、解封温度和封端效果;分别考察了封闭剂对膜力学性能与热性能的影响。结果表明,差示扫描热量法显示苯酚和甲乙酮肟的封端反应温度分别为100 ℃和80 ℃;从封闭效果、膜的力学性能及环保角度分析比较,甲乙酮肟作聚醚型预聚体的封闭剂优于苯酚,甲乙酮肟封闭预聚体扩链后膜的拉伸强度为25.1 MPa,断裂伸长率为424 %;热重分析表明膜的热性能基本不受封闭剂种类的影响。  相似文献   

11.
Synthesis and properties of new initiating systems formed from commercially available ketones, glycols, and hydrogen peroxide (60%) are presented. In preparation of free radical initiators methyl ethyl ketone, which was oxidized by hydrogen peroxide, was used. Reaction was carried out in etanodiol or 1,4‐butanodiol as diluent. The obtained initiators with cobalt octoate as a promotor were applied for crosslinking of the commercially available unsaturated polyester resin. Properties of the resin were compared with those obtained while it was hardened by the typical curing system containing methyl ethyl ketone hydroperoxide and cobalt octoate. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 2238–2243, 2003  相似文献   

12.
Formation of methyl ethyl ketazine is a distinct case of homogeneous catalyzed gas–liquid–liquid reactions. Kinetics studies of methyl ethyl ketazine formation has been carried out in a semi‐batch reactor. The effects of temperature and catalyst concentration on the percentage yield of ketazine have been studied extensively. The yield of ketazine is found to increase with increase in temperature and then levels off. Increase in catalyst concentration favours the formation of ketazine. The conversion of peroxide is found to increase with increase in temperature thus indicating that chemical reaction is rate‐limiting step in the system. The desired temperature for carrying out the reaction is found to be 60°C and the required catalyst to peroxide ratio is 2.5. The activation energy for the reaction is 24.5 kJ/mol.  相似文献   

13.
过氧化甲乙酮合成研究   总被引:2,自引:0,他引:2  
研究了在酸性催化剂存在下,以邻苯二甲酸二丁酯作溶剂,由双氧水和甲乙酮作用制取过氧化甲乙酮溶液的工艺,并得到最佳工艺条件。结果表明,产品性能优良。  相似文献   

14.
成分比例不同的MEKP固化不饱和聚酯树脂研究   总被引:2,自引:0,他引:2  
通过45,50,55和60℃等温DSC固化研究了成分(过氧化氢、MEKP单体和二聚体)比例不同的过氧化甲乙酮(MEKP)对不饱和聚酯树脂(UP)固化诱导期、峰值时间和固化率的影响,并讨论了固化引发机理。结果发现,过氧化氢质量分数较少、单体和二聚体质量比为1.5∶1的MEKP对UP固化有利。  相似文献   

15.
水合肼中间体丁酮连氮的合成工艺研究   总被引:2,自引:0,他引:2  
以丁酮、氨气和过氧化氢为原料,研究了在催化剂条件下水合肼中间体丁酮连氮合成的不同工艺条件;考察了催化剂种类及其用量、反应时间、反应温度、双氧水用量各因素对反应收率的影响,结果显示,当催化剂选用甲酰胺,催化剂用量0.5mol,反应时间6h,双氧水用量为0.5mol时,反应温度60℃,丁酮连氮收率达到83.49%。  相似文献   

16.
采用金属Mn对铜锌铝催化剂进行改性,以二氟乙酸乙酯加氢制备2,2-二氟乙醇的反应体系评价催化剂性能,考察工艺条件对催化剂上二氟乙酸乙酯转化率和2,2-二氟乙醇选择性的影响。结果表明,反应温度对催化剂活性影响最大,其次是氢酯比,反应压力和原料空速对产物的选择性影响较小。在反应温度200℃、反应压力4.0 MPa、空速0.1 mL·(g·h)~(-1)和氢与酯物质的量比为60条件下,2,2-二氟乙醇选择性100%,二氟乙酸乙酯转化率72.3%。催化剂稳定性好,连续运行900 h仍然保持较好的催化活性。  相似文献   

17.
The influence of the technological parameters on the course of the epoxidation of allyl alcohol with 30% H2O2 in the presence of titanium silicalite TS‐2 catalyst and methanol as a solvent was studied. The process was performed in an autoclave at the autogenic pressure. The influence of temperature in the range 20–120 °C, molar ratio of allyl alcohol/H2O2 (1:1–10:1), methanol concentration in the reaction mixture (10–80% w/w), catalyst TS‐2 concentration (0.1–2.0% w/w) and reaction time (1–8 h) were investigated. The functions describing the process were: selectivity of transformation to glycidocidol in relation to allyl alcohol consumed, selectivity of transformation to organic compounds in relation to hydrogen peroxide consumed, conversions of allyl alcohol and hydrogen peroxide. Copyright © 2007 Society of Chemical Industry  相似文献   

18.
In this paper, nine different catalysts have been used for the epoxidation of methyl oleate with hydrogen peroxide as oxidant. The prepared catalysts were mostly based on supported systems niobia–alumina and niobia–silica. Experimental runs were carried out in a lab-scale reactor, keeping constant operating parameters such as reaction temperature (80?°C) and time (5 h), and molar ratio between oxidant and methyl oleate (equal to 4). Runs aimed at the quantitative evaluation of system conversion, yield and selectivity. Nb2O5/SiO2 were found to be active in epoxidation reaction, in particular the catalyst with intermediate niobia loading (6% w/w) showed very high conversion (77%) even if with a very low selectivity to epoxides (30%). Instead, regarding the system based on Nb2O5/Al2O3, both better activity and selectivity were reached. In particular, the material containing 12% of Niobia yielded the highest values for conversion (83%) and selectivity (89%). The results have been critically discussed through the outcomes of a deep characterization of the catalytic materials, carried out through porosimetric, X-ray diffraction, ultra violet and visible diffuse reflection, and Raman microscopy analyses. The discussion highlighted the more relevant parameters able to influence the activity of niobia-based catalysts in the methylesters epoxidation.  相似文献   

19.
过氧化甲乙酮合成工艺的探讨   总被引:1,自引:0,他引:1  
着重介绍了以磷酸做催化剂,用过氧化氢和丁酮为原料,室温下制备过氧化甲乙酮,在获取大量实验数据的前提下,确定生产过氧化酮的最佳工艺条件。  相似文献   

20.
在以强酸型离子交换树脂为催化剂和过氧化氢为氧化剂的清洁工艺条件下,首次研究了选择性氧化苯甲硫醚生成苯甲亚砜的反应,优化得到了合成苯甲亚砜的最佳工艺条件为:反应底物苯甲硫醚8 mmol、反应溶剂甲醇10 mL、反应温度为常温、反应时间为8 h、催化剂用量为底物摩尔量的50%、过氧化氢与底物摩尔比为1.0∶1.0。此反应的转化率和选择性均大于99.9 %,催化剂重复使用15次未见其活性和选择性明显下降。在类似的反应条件下, 其它4种硫醚也被高效和选择性地氧化为相应的亚砜。  相似文献   

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