共查询到20条相似文献,搜索用时 78 毫秒
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研究了以偏硼酸为催化剂的环十二烷常压空气氧化制环十二醇、酮的反应规律,采用鼓泡搅拌釜作为反应器,在间歇操作方式下,通过改变通氧速率、搅拌转速、反应温度、催化剂用量,测定了反应液中烷、醇、酮的浓度随反应时间的变化关系,得到了醇、酮选择性与烷转化率的关系,确定了适宜的工艺操作条件。在连续操作方式下,通过改变烷的进料速度,测得了反应产物中烷、醇、酮的浓度随空时的变化关系,并与间歇操作获得的实验结果进行了比较。 相似文献
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综述Salen-Mn配合物,手性酮,生物酶催化剂催化的不对称环氧化反应研究进展情况,详细介绍了酮催化剂的发展趋势。 相似文献
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研究了以偏硼酸为催化剂的环十二烷空气液相氧化制取环十二烷醇(酮)的工艺条件对氧化过程的转化率、选择性及收率的影响。提出了连续氧化操作更为合理的设想,并给出相应的工艺条件。 相似文献
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钼基催化剂在烯烃液相环氧化反应中的应用研究进展 总被引:1,自引:1,他引:0
介绍了钼络合物催化剂、固载化的钼络合物催化剂及MoO3基的固体钼催化剂在烯烃液相环氧化反应中的应用。以有机过氧化物为氧化剂时,不同的钼基催化剂均表现出很好的催化性能,其中络合物中的配体对其催化性能有很大影响,并且可以通过引入手性配体实现对烯烃的不对称环氧化,而固体钼催化剂的性能则与载体上钼物种的种类密切相关。但绝大多数钼催化剂对H2O2参与的环氧化反应没有活性,开发对H2O2有催化活性的钼基催化剂是一个重要的研究方向。 相似文献
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文章制备了水溶性的四(4-甲基吡啶基)锰卟啉(MnTM4PyP),然后通过浸渍法在水溶液中将锰卟啉负载到蒙脱土上制备了锰卟啉/蒙脱土催化剂(MTM4PyP/MT)。在室温条件下,用此固载型卟啉作为催化剂选择性催化氧气环氧化烯烃到相应的环氧化物。试验结果表明此催化剂可以高活性、高选择性地催化烯烃的环氧化反应,而且可以多次重复使用。 相似文献
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Michael J. Walker 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1991,50(3):369-377
The paper describes the properties of a number of novel variants of sodium perborate bleach suitable for laundry and automatic dish wash detergent formulations, highlighting their advantages over standard commercial products, and offering further opportunities of product differentiation for the detergent manufacturers. 相似文献
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L. T. Murray 《Journal of the American Oil Chemists' Society》1968,45(7):493-496
Presently two classes of fabric bleaching agents, the chlorine and oxygen types, are employed in home laundering. Although
these two classes of bleaches are employed, there is a vast difference in their effectiveness. The chlorine bleaches function
well under most time and temperature conditions practiced in fabric laundering in the United States, but equivalent effectiveness
with the oxygen type can only be obtained under longer time or higher temperature use conditions.
This paper represents a review of the relative performance and cost of the two classes and concentrates on the considerable
research activity of the last 20 years, directed toward finding routes to increased bleaching effectiveness with sodium perborate.
The chemistry of these approaches, consisting primarily of the use of the so-called organic activators and metal ion catalyst
systems, is discussed along with a discussion of effectiveness, cost, and potential utility. 相似文献
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四乙酰乙二胺对过硼酸钠活化作用的研究 总被引:1,自引:0,他引:1
研究了四乙酰乙二胺(TAED)对过硼酸钠(SPB)在低温下释氧和漂白的活化作用及影响因素,对特种污布进行了漂白试验。结果表明:由于TAED的存在,SPB可在40℃-60℃内很好地发挥漂白活性。 相似文献
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以硼砂和消石灰为原料制备偏硼酸钙(CaO·B_2O_3·6H_2O),同时得到富含偏硼酸钠的母液.在一定温度下将母液蒸发结晶得固体偏硼酸钠,再与30%的过氧化氢在稳定剂存在下经反应、过滤及干燥制备出四水过硼酸钠(NABO_3·4H_2O),最后经减压脱水制得一水过硼酸钠(NaBO_3·H_2O).通过对物料配比、反应温度、反应时间、液固比及稳定剂的种类进行考察,确定了适宜的工艺条件,即配料摩尔比n(NaBO_2·4H_2O):n(H_2O_2)=1∶1.1,液固比3.3∶1(mL/g),反应温度25~30℃,反应时间60~75 min,稳定剂为聚丙烯酸.在此工艺条件下制得的四水过硼酸钠产品含B2_O_3 22%~24%、NAB0_3·4H_2O≥96%、活性氧含量在10%以上,Fe≤0.004%;脱水得到的一水过硼酸钠产品的活性氧为15%左右. 相似文献
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Halil Demir 《Korean Journal of Chemical Engineering》2011,28(10):2002-2008
Model-free and model-fitting methods have been applied to data for nonisothermal and isothermal decomposition of sodium perborate tetrahydrate to sodium metaborate. The kinetic triplet (f(a), A and E) of sodium perborate tetrahydrate was found by model fitting method defined with a single step reaction, which has an excellent fit for nonisothermal data and obeys different kinetic models and yields highly uncertain values of Arrhenius parameters. The isothermal and nonisothermal data for thermal decomposition of sodium perborate tetrahydrate to sodium perborate monohydrate and sodium metaborate were evaluated by model-free isoconversional method. The complex nature of multi-step process of sodium perborate tetrahydrate to sodium metaborate was more easily indicated by using wide temperature range in nonisothermal isoconversional method. 相似文献
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G. E. M. Moussa S. O. Abdalla 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1970,20(8):256-260
The oxidation of 1,1,2-triphenylbut-1-ene by chromium trioxide in acetic anhydride gives 1,2-epoxy-1,1,2-triphenylbutane with fission products and 1,1,2-triphenylacetylethylene. Cis- and trans-1-p-chlorophenyl-1,2-diphenylprop-1-ene yield crystalline epoxides in satisfactory yields under similar conditions. The epoxides are stable towards aqueous sulphuric acid. 1,1,2-Triphenylethylene, 1,1-di-(p-chlorophenyl)-2-phenylethylene and 1,1-di-(p-bromophenyl)-2-phenylethylene are similarly oxidised but the epoxides are hydrated to the glycols by the action of aqueous sulphuric acid. Chromic acid in aqueous sulphuric acid brings about oxidative fission of the double bond without any rearrangement. 相似文献
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Prashant N. Mandare 《Chemical engineering science》2003,58(7):1125-1133
Semi-batch reactive precipitation of sodium perborate tetrahydrate was studied in a stirred reactor. Effect of hydrodynamic parameters and reactant concentrations on the average crystal size was examined and it was found that secondary nucleation plays a dominant role in deciding the final crystal size. The data of average crystal size was correlated with power consumption per unit mass and solid loading. 相似文献