Octane Research Papers - Academia.edu (original) (raw)

The octane number of gasoline is one of the most important measures of gasoline quality to predict accurately the octane ratings of blending gasolines. This measured on a scale that ranges from that equivalent to isooctane (octane number... more

The octane number of gasoline is one of the most important measures of gasoline quality to predict accurately the octane ratings of blending gasolines. This measured on a scale that ranges from that equivalent to isooctane (octane number of 100) to that of n-heptane (octane number of zero) octane no is effected by the saturates, aromatics, and olefins contents of gasoline. We take it as a standard and measure octane number by comparison with this standard. The accurate octane blending method will optimize the blending of gasoline components, when gasoline components are blended together, we will calculate the octane number of the blend with different octane number of the component or if the four components are of equal octane number. The blend octane number may be greater than, equal to or less than that calculated from the volumetric average of the octane numbers of the blend components, which indicates nonlinear blending. Blending would be linear if octane number of a blend was equal to that predicted by summing the octane numbers of the components in proportion to their concentrations. In practices, the discrepancies between the octane numbers of blends and the linearly predicted values have been correlated by specific empirical equations and these have been used to correct the linear predictions.

The octane enhancement of light straight run naphtha is one of the significant solid acid catalyzed processes in the modern oil refineries due to limitations of benzene, aromatics, and olefin content in gasoline. This paper aims to... more

The octane enhancement of light straight run naphtha is one of the significant solid acid catalyzed processes in the modern oil refineries due to limitations of benzene, aromatics, and olefin content in gasoline. This paper aims to examine the role of various catalysts that are being utilized for the isomerization of light naphtha with an ambition to give an insight into the reaction mechanism at the active catalyst sites, and the effect of various contaminants on catalyst activity. In addition, different technologies used for isomerization process are evaluated and compared by different process parameters.

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... more

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 ori stream and lower cost can be developed.
This review covers recent developments in reforming catalysts, process
reaction chemistry and mechanism. It also highlights prospective areas of
research.

The purpose of this paper is to review recent studies on catalytic conversion of benzene in reformate by hydrogenation, hydroisomerization, and alkylation. Refineries throughout the world are facing challenges in meeting new fuel... more

The purpose of this paper is to review recent studies on catalytic conversion of
benzene in reformate by hydrogenation, hydroisomerization, and alkylation.
Refineries throughout the world are facing challenges in meeting new fuel
specifications; one of them is benzene content in motor gasoline. Almost all the
proposed benzene reduction processes are within the naphtha processing area,
since the reformate is the major source of benzene (typically in the range 2.5-8.0
vol.%), as well as the major component in the gasoline pool. The catalytic
conversion approach discussed in this paper is the most flexible one since it allows
accurate monitoring of the benzene without altering the operation of the reformer
unit. The present paper also briefly compares the costs of various benzene
reduction options and their impact on refinery economics.

Excess molar enthalpies for the ternary system 1, 4-dioxane (1)+ n-octane (2)+ cyclohexane (3) and for the three constituent binary systems have been measured by a Calvet microcalorimeter at 303.15 K and ambient pressure. The experimental... more

Excess molar enthalpies for the ternary system 1, 4-dioxane (1)+ n-octane (2)+ cyclohexane (3) and for the three constituent binary systems have been measured by a Calvet microcalorimeter at 303.15 K and ambient pressure. The experimental binary results were ...

Catalytic naphtha reforming is the technology that combines catalyst, hardware, and process to produce high-octane reformate for gasoline blending or aromatics for petrochemical feedstocks. Reformers are also the source of much needed... more

Catalytic naphtha reforming is the technology that combines catalyst, hardware, and
process to produce high-octane reformate for gasoline blending or aromatics for
petrochemical feedstocks. Reformers are also the source of much needed hydrogen for hydroprocessing operations. Several commercial processes are available worldwide, and the licensing of technology for semiregenerative and continuous reforming is dominated by UOP and Axens (formerly IFP) technologies.
The main difference between commercial reforming processes are catalyst
regeneration procedure, catalyst type, and conformation of the equipment. Currently,
there are more than 700 commercial installations of catalytic reforming units worldwide, with a total capacity of about 11.0 million barrels a day. About 40% of this capacity is located in North America followed by 20% each in western Europe and the Asia—Pacific region. Table 1 presents a regional distribution of catalytic reforming capacity worldwide[1].
This chapter presents an overview of latest developments in reforming technology,
describes major licensed processes, and includes recent introductions of reforming
catalysts.

The hydroisomerization of n-octane has been catalyzed by different zeolitic structures with large pore size (12 MR). It has been seen that channel topology, chemical composition, crystal size, and adsorption properties are of paramount... more

The hydroisomerization of n-octane has been catalyzed by different zeolitic structures with large pore size (12 MR). It has been seen that channel topology, chemical composition, crystal size, and adsorption properties are of paramount importance for improving the isomerization activity and selectivity. Nanocrystalline beta zeolite (30 nm) with large pore size (0.66 × 0.67 and 0.56 × 0.56 nm), and high aluminum content (Si/Al = 16), was the best catalyst to produce multibranched isomers. Cracking reactions also occur together with isomerization and the product distribution will depend on the rate constant and relative activation energies of isomerization, desorption, and cracking. Furthermore, a complete kinetic study of n-octane isomerization has been carried out with beta zeolite, and kinetic rate constants, heats of adsorption, and activation energies have been determined for each individual isomerization step. The rate of isomerization of n-octane to monobranched products was found to be faster than the rate of cracking of dibranched products and the rate of isomerization of mono- to dibranched products. It should be possible to obtain high yields of dibranched alkanes by distillation and recycling units, or by using membrane reactors.

Compositions of polymers (polyethylene and polyuretane) and fillers (initial silica and silicas modified with: N-2-aminoethyl-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxy-silane, 3-merkaptopropyltrimethoxysilane,... more

Compositions of polymers (polyethylene and polyuretane) and fillers (initial silica and silicas modified with: N-2-aminoethyl-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxy-silane, 3-merkaptopropyltrimethoxysilane, octyltriethoxysilane) were examined by inverse gas chromatography at 383K. Small amounts of the following test solutes were injected to achieve the infinite dilution conditions: pentane, hexane, heptane, octane, nonane, dichloromethane, chloroform, carbon tetrachloride and 1,2-dichloroethane.The retention times for these test solutes were determined

Gasoline is a complex mixture that possesses a quasi-continuous spectrum of hydrocarbon constituents. Surrogate fuels that decrease the chemical and/or physical complexity of gasoline are used to enhance the understanding of fundamental... more

Gasoline is a complex mixture that possesses a quasi-continuous spectrum of hydrocarbon constituents. Surrogate fuels that decrease the chemical and/or physical complexity of gasoline are used to enhance the understanding of fundamental processes involved in internal combustion engines (ICEs). Computational tools are largely used in ICE development and in performance optimization; however, it is not possible to model full gasoline in kinetic studies because the interactions among the chemical constituents are not fully understood and the kinetics of all gasoline components are not known. Modeling full gasoline with computer simulations is also cost prohibitive. Thus, surrogate mixtures are studied to produce improved models that represent fuel combustion in practical devices such as homogeneous charge compression ignition (HCCI) and spark ignition (SI) engines. Simplified mixtures that represent gasoline performance in commercial engines can be used in investigations on the behavior of fuel components, as well as in fuel development studies. In this study, experimental design was used to investigate surrogate fuels. To this end, SI engine dynamometer tests were conducted, and the performance of a high-octane, oxygenated gasoline was reproduced. This study revealed that mixtures of iso-octane, toluene, n-heptane and ethanol could be used as surrogate fuels for oxygenated gasolines. These mixtures can be used to investigate the effect of individual components on fuel properties and commercial engines performance.