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不同结构硫化钼催化剂上酚类模型化合物的加氢脱氧 总被引:5,自引:0,他引:5
Several MoS2 catalysts of different structure, prepared by in situ decomposition of ammonium heptamolybdate (AHM) and molybdenum naphthenate (MoNaph), and by MoS2 exfoliation (TDM), were characterized by BET, X-ray diffraction (XRD), Energy Dispersive X-ray (EDX) and transmission electron microscopy (TEM). The analysis showed that MoS2 structure was dependant upon the preparation procedure. The activity of the catalysts was determined by measuring the hydrodeoxygenation (HDO) of phenol, 4-methylphenol and 4-methoxyphenol using a batch autoclave reactor operated at 2.8 MPa of hydrogen and temperatures ranging from 320-370℃. By comparing the conversion, the reactivity order of the catalysts was: AHM〉TDM-D〉MoNaph〉thermal〉MoS2 powder〉 TDM-W. Also, the effect of reaction temperature on the HDO conversion was explained in terms of equilibrium of reversible reaction kinetics. The main products of the HDO for phenolic compounds were identified by gas chromatography/mass spectrometry (GC/MS). The results showed that the product distribution and the HDO selectivity were correlated with the reaction temperature. Two parallel reaction routes, direct hydrogenolysis and combined hydrogenation-hydrogenolysis, were confirmed by the analysis of the product distribution. High temperature favored hydrogenolysis over hydrogenation for HDO of phenol and 4-methoxyphenol, whereas for 4-methylphenol the reverse was true. 相似文献
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结构片断法计算离子型表面活性剂的HLB值 总被引:1,自引:0,他引:1
运用结构片断法计算离子型表面活性剂的疏水值logP,并将疏水值概念引入Davies基团贡献法以代替该模型中亲油基的基团数,从而建立了计算离子型表面活性剂HLB值的新模型为:HLB=7+∑亲水基基团数-∑疏水基logP。通过与文献列举的17个不同系列离子型表面活性剂的HLB值对照表明,该新模型的计算值与文献值的平均相对偏差为1.68%。采用非线性方法拟合了烷基硫酸钠,烷基磺酸钠和烷基三甲基溴化铵3类典型离子型表面活性剂的CMC和HLB的关系,并得到了其关联方程,拟合结果表明,由新模型得到的关联方程其复相关系数R2>0.988。 相似文献
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流动注射-分光光度法测定环境水样中微量铀 总被引:6,自引:0,他引:6
在硝酸介质中,铀(Ⅵ)可与2-(3-羧基苯偶氮)-7-(4-氯-2-膦酸基苯偶氮)-1,8-二羟基-3,6-萘二磺酸(CPA-mK)迅速反应生成蓝色配合物,据此建立了一种新的测量微量铀的流动注射光度法。方法的检出限为0.032mg/L,U(Ⅵ)量在0~35mg/L范围内符合比尔定律。方法用于测定环境水样中微量铀,结果满意。 相似文献
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利用金属制品生产过程中所产生的盐酸酸洗废液,进行非氯氧化法制取三氯化铁的工业试验研究,探讨了温度及压力、搅拌方式、催化剂的加入方式及加入量等对FeCl_3制备反应的影响,并对蒸发浓缩的效果及工艺的稳定性作了分析。 相似文献
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以碱共沉淀法制备Mg-Al水滑石,然后采用浸渍法负载活性组分Pt,经焙烧、氢气还原得到Pt/Al_2O_3与Pt/Mg O-Al_2O_3催化剂,采用XRD、N2吸附-脱附、FT-IR、H2-TPR和Py-IR等分析Mg O的加入对Pt/Al_2O_3催化剂结构性能的影响,并在甲基环己烷连续脱氢反应中对比两种催化剂活性。结果表明,Pt/Mg O-Al_2O_3催化剂比表面积小于Pt/Al_2O_3催化剂,且表面基本无酸性活性中心,但表现出与Pt/Al_2O_3催化剂相同的脱氢活性。在Pt负载质量分数2%、催化剂用量0.5 g、甲基环己烷0.1 m L·min-1纯样进料和325℃反应10 h后,原料平均转化率79.9%,脱氢产物只有甲苯,对应的产氢速率192.8 mmol·(g-metal·min)-1,表现出优良的脱氢活性。 相似文献
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