摘要:

Catalytic reforming of naphtha remains the key process for production of high octane gasoline and aromatics (BTX) which are used as petrochemicals feedstocks. The increased demand for these products has led refiners to investigate ways for improving the performance of the reforming process and its catalysts. Moreover, in order to comply with environmental restrictions, the reduction in lead content would require further increase in the reformate octane number. In response to these requirements, refiners and catalyst manufacturers are examining the role of the catalysts in improving the selectivity to aromatics and in octane enhancement. By understanding the chemistry and the mechanism of the reforming process, higher performance catalysts with longer life on stream and lower cost can be developed.

ISSN:0884-3759    

DOI:10.1080/08843759108942250

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

The effect of temperature and NiCl2-KCl-LiCl (14:36:50 molar percentages) catalyst on tetralin7sol;naphthalene ratio in the absence and presence of Beypaian lignite was determined. The amounts or tctralin and naphthalene present in the liquid products were determined by gas chromatography. The tetralin/naphthalene ratio decreased from 49 to 47 and 31 in noncatalytical experiments performed in the absence of lignite at 270°C 300°C and 360°C, The lowest tetralin/naphthalene ratio was observed at 360/C and this indicated that the highest amount of hydrogen radicals was supplied by tetralin at this temperature. Therefore it was reasonable to assume that the highest conversion to liquid products might have occurred at this temperature. While the amount of catalyst added was increased from 0.00 to 0.50 the tetralin/naphthalene ratio decreased to its minimum values for all the experiments done at 275°C, 300°C and 360°C. In experiments with coal the tetralin/naphthalene ratio was about 5 times smaller than the value of the ratio in experiments without coal. This indicated that, in the presence of coal, the tetralin→ naphthalene reaction was strongly forced to proceed in the direction of the arrow.

ISSN:0884-3759    

DOI:10.1080/08843759108942251

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Contact angle measurements were carried out in coal ranks of 32.1 and 32.2/n-alkane film - air bubble - aqueous diacetone solution systems. In these studies n-alkanes in homological series from n-hexane to n-hexadecane and aqueous diacetone alcohol solutions in concentration range from 0 to 10% were used. On the basis of obtained results the adhesion work of aqueous diacetone alcohol solutions to coal surface precovered with n-alkane film was calculated from the modified Young equation. These investigations showed that an increase of n-alkane film thickness causes a decrease of the wettability of low-rank coals as well ob a decrease of the adhesion work of aqueous diacetone alcohol solutions to coal/n-alkane film surface. An increase of the may be also stated, that an increase of the quantity of diacetone alcohol molecules adsorbed on coal surface precovered by a small amount of hydrocarbon causes a decrease of the adhesion work, but when the coal surface is precovered by a big amount of hydrocarbon the adhesion work is increased.

ISSN:0884-3759    

DOI:10.1080/08843759108942252

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

A logical next step in verifying the viability of emerging oil shale technologies in the United States is an engineering-scale demonstration. A joint industry-government study recently completed for a proof-of-concept demonstration at Colorado Tract C-b revealed the cost and benefits of such a demonstration using modified in situ (MIS), circulating fluidized bed combustion (CFBC) and above ground retorting (AGR) processes. A partnership between industry and local, state, and federal governments is being proposed to carry out the program.

ISSN:0884-3759    

DOI:10.1080/08843759108942253

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Differential Scanning Calorimetry (D.S.C.) has been used to characterize the thermal behavior of various paving asphalts and their chromatographic fractions. In a single determination, several parameters, such as the glass transition temperature of the hydrocarbon matrix and the crystallized fractions, may be determined with good reproducibility. The glass transition is attributed to the aromatic and one part of the saturated fractions. The rest of the satured fraction has been found responsible for the endoihermal effect observed on warming which corresponds to the dissolution into the matrix. A method of determination of the crystallized fractions is described, and a comparison with the L.C.P.C. (Laboratoire Central des Ponts et Chaussdes - French Highway Administration Laboratory) method is made. The L.C.P.C. method was found to underestimate the real percentage of the crystallized fractions.

ISSN:0884-3759    

DOI:10.1080/08843759108942254

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Atmospheric pressure pyrolysis for the production of liquids and gases from black liquor and its calcium salts and acidic precipitate have been carried out in a little stainless steel tube. Yields, sum of liquid and gas products, from black liquor and its calcium salts and acidic precipitate were 44.7 %, 52.0 % and 59.1 % of dry basis respectively. The precipitates obtained from black liquor by acidifying with hydrochloric acid and passing carbon dioxide have been polymerized in aqueous acetone containing formaldehyde and ammonia, and converted a polymeric resin.

ISSN:0884-3759    

DOI:10.1080/08843759108942255

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

ISSN:0884-3759    

DOI:10.1080/08843759108942256

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

ISSN:0884-3759    

DOI:10.1080/08843759108942249

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor