摘要:

In the liquid phase methanol synthesis process, syngas reacts in the presence.of fine catalyst particles slurried in the oil phase, in a three phase slurry reactor system. A method for activating high concentration ( ⩽25 wt. %) of the CuO-ZnO-Al2O3catalyst in the catalyst-oil slurry has been successfully developed. This catalyst activation process can be of crucial significance in the research and development of the methanol synthesis process in a liquid entrained reactor.

ISSN:0884-3759    

DOI:10.1080/08843759608947608

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

The reaction between CO2and CH4was carried out in a fixed-bed continuous flow reactor over y-alumina supported nickel metal, reaction temperature was 773-1073°K and reaction pressure 0.1-0.13MPa with different ratios of CH4C02. Catalysts were characterized by SEM, XRD, XPS and IJTA. It was found that Ni/y-alumina had higher activity, selectivity and stability when it was made in strong acid(pH⩽2) or strong base (pH⩽ll) solution. In this reaction syngas with lower ratios of H2/CO was produced.

ISSN:0884-3759    

DOI:10.1080/08843759608947609

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Quantitative description of the correlations between some characteristics (density, viscosity, asphaltene and sulfur contents, stability ) of the vacuum residues and products of their visbreaking, and of the changes in the feed properties as a result of visbreaking in a real commercial visbreaker was done. The asphaltenes contents is higher in the petroleum products having higher density and viscosity. The higher the feed viscosity, the higher the visbreakate viscosity, but also the higher the relative decrease in the viscosity. There is no correlation between stability and the asphaltenes contents both for the feed and for the visbreakate. The higher the asphaltenes contents in the feed, the lower the relative increase in the asphaltenes contents during visbreaking. It indicates prevailing reactions of condensation of the asphaltenes precursors (resins, etc.) for the light stocks. For heavier stocks, cracking of the asphaltenes plays more significant role; starting from the asphaltene content in the feed of 7-9 %, reactions of the condensation and cracking are approximately of the same rate, and increase in asphaltene content takes place mainly due to concentrating them in the visbreaking residue as a result of distillation of the visbroken product. Two groups of feedstocks may be defined from the point of view of their behavior in visbreaking: low-sulfurized (Scl%) andhigh-sulfurized ones (S⩽2%). In the feedstocks with low sulfur contents, the asphaltenes contents increases sharply, whereas for the high-sulfurized stocks the relative increase in the asphaltenes contents is low.

ISSN:0884-3759    

DOI:10.1080/08843759608947610

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Hydrodesulfuization of benzothiophene has been investigated over a Ni-Mo/y-A1203catalyst. Kinetic data were taken in a flow microreactor system at temperatures of 180 to 260 °C and 2.0 MPa hydrogen pressure, at various weight hourly space time. From the data, kinetic midel after Langmuir-Hinshelwood relationship kinetics were developed to predict the rate of disappearance of benzothiophene and that for formation of the dihydrobenzothiophene as a intermediate product.

ISSN:0884-3759    

DOI:10.1080/08843759608947611

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

The present work describes a study of the liquefaction and pyrolysis of a Southern Brazilian mineral coal and its derived asphaltenes, using conversion systems developed in our laboratory.

ISSN:0884-3759    

DOI:10.1080/08843759608947612

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Mosshauer spectroscopy (MES) has been used to study the characteristics of iron catalysLs preireated in different ways for Fischer-Tropsch (F-T) synthesis. The Mosshauer spectrum results showed that the fine particle of α-Fe2o3is the main phase of oxide catalyst. Catalysts preireated in H2:CO ratio of 2.1 syngas at 250°C and under 0.5 MPa with the gas hourly space velocity of 1500 h−for 32 h in a fixed-bed reactor resulted in the reduction of 91% of iron to Fe3o4, FeO and X-FC5C2- The κ-Fe5s2content of reacted catalyst increased greatly as compared with reduced catalyst, while FeO and Fe3o4contents decreased. The Fe3O4content of catalyst poisoned by oxygen increased as compared with reduced catalyst. FeS2is the main phase of catalyst poisoned at high COS concentration, while FeS is the main phase of catalyst poisoned by COS al low concentration. The Fe3o4content decreased with the increase of sulfur fed to catalyst. The deactivation rate is related to the composition of the catalyst treated in concentrations.

ISSN:0884-3759    

DOI:10.1080/08843759608947613

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

A three step process is proposed for stabilizing thermal residues and bitumens, such as visbreaker residues, and for upgrading SR bitumens used to produce stable polymer-modified bitumens.

ISSN:0884-3759    

DOI:10.1080/08843759608947614

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Two vacuum residues of heavy petroleum blends and residues of the products of their visbreaking, on a commercial unit, were investigated by means of column chromatography, cryoscopic analysis, elemental analysis, NMR spectroscopy, etc. An increase in the contents of asphaltenes and saturated, increase in asphaltenes/polar components ratio, and decrease in the aromatics contents during visbreaking were observed for both kinds of feed. The N/C ratio increased, the S/C ratio did not change significantly. Most of the nickel and vanadium were concentrated in the asphaltenes and aromatics. The length of the paraffinic chains of the saturated decreases during visbreaking from about 50 to 30 carbon atoms. The number of carbon atoms per alkyl chain and the number of naphthenic rings in the average molecule of the aromatics decreased, whereas the number of aromatic rings increased. About 2/3 of the total aromatic carbon in the aromatics are non-bridged. The average asphaltenes molecule contains about 36-38 aromatic rings (mostly condensed), 5-7 naphthenic rings and 12-16 alkyl substituents having relatively short (n = 5-6) chains. Two contrary processes, relating asphaltenes, take place during visbreaking: 1) cracking of asphaltenes, which results in a decrease in their content and molecular weight, decrease in the number of the side chains and their length, and increase in asphaltenes aromaticity; 2) asphaltenes formation from the polar components of the feed. The resulting process may be expressed both in a decrease and in an increase in the asphaltenes content. Reactions of condensation of the asphaltenes precursors (resins, etc.) prevail for the light stocks. For heavier stocks, cracking of the asphaltenes plays a more significant role, and the increase in asphaltenes content takes place mainly due to concentrating them in the visbreaking residue as a result of the distillation of the visbroken product.

ISSN:0884-3759    

DOI:10.1080/08843759608947615

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:0884-3759    

DOI:10.1080/08843759608947616

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor