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1.
Kinetic regularities of methylmercaptan production from dimethyl sulfide and H2S in the presence of -Al2O3 have been studied under gradientless conditions. A stepwise reaction mechanism is suggested implying that the catalyst surface is methoxylated by methyl sulfide and then CH3O groups interact with H2S. The kinetic equation obtained describes fairly well this process on the nonhomogeneous catalyst surface. H2S -Al2O3. , , CH3O- H2S. , .  相似文献   

2.
The reaction of DDQ with imidazole in acetonitrile is a two-step process. The formation of an anion radical is followed by slow substitution of Cl atoms to form diaminobenzoquinone. Kinetics of the second step is reported. . - Cl CN- . .  相似文献   

3.
The effect of strong metal-support interaction (SMSI) has been studied over Rh/TiO2 as a model catalyst. Adsorbability variations during SMSI state generation have been found to be due to the production of Rh–Ti alloy. - Rh/TiO2. , SMSI Rh–Ti.  相似文献   

4.
Factors leading to abnormally high fractal dimension D of silica surfaces measured by adsorption of aliphatic alcohols have been analyzed. , D .  相似文献   

5.
The dehydroxylation of 3610 cm–1 OH groups in HZSM-5 zeolite and in two Ni and Mo modified catalysts containing the same zeolite has been studied at 673 K. The presence of water vapor is a necessary condition of dehydroxylation, the extent of which depends on the number and duration of breaks consisting in cooling to room temperature and reheating to 673 K with evacuation. OH HZSM-5, Ni Mo- , 3610 cm–1, 673 . , 673 .  相似文献   

6.
Liquid-phase alkylation of p-tert-butylphenol (TBP) and p-cresol by olefins and benzyl chloride in the presence of solid heteropoly acids (HPA) H3PW12O40 and 25% H3PW12O40/SiO2 at 100–150°C provides high yields of mono- and disubstituted products. HPAs are more active than H2SO4, easily separated from the reaction mixture and can be used repeatedly. -- () - () H3PW12O40 25% H3PW12O40/SiO2 100–150°C - - . , H2SO4, - - .  相似文献   

7.
The oxidation of MnEDTA2–. (EDTA=ethylenediaminetetra-acetate) by hexachloroiridate(IV) has been studied in concentrated electrolyte solutions at 298 K. The estimation of the activity coefficients of the species from the Stokes-Robinson hydration theory indicates that the observed salt effects have their origin in a greater destabilization of the initial state with respect to the transition state when increasing salt concentration. MnEDTA2– (EDTA= ) (IV) . -, , .  相似文献   

8.
Some general dependences of the injection volumes of reaction components on time have been derived for the feedback controlled chemical reactor. .  相似文献   

9.
Kinetic study of C2H4 polymerization on reduced V2O5/Al2O3 catalysts revealed that the rate equation can be expressed as V=k exp (-Y) KaPE/(1+KaPE) in the temperature range of –20 to 70°C. The deactivation constant, , was found to have a close relation with the yield and molecular weight of the polymer. C2H4 V2O5/Al2O3 –20 +70°C : Vp=k·exp(-Yp)·KaPe/(1+KaPe). .  相似文献   

10.
The second-order rate constants, activation parameters and primary deuterium isotope effects are reported for the proton-transfer reactions from di (4-nitrophenyl)-methane to sodium ethoxide, iso-propoxide and t-butoxide in appropriate alcohols. The mechanism for the reaction is discussed. , -(4-) , - . .  相似文献   

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