How does a change in the dry point of gasoline affect its octane rating and sulfur content?
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As the title suggests, I earnestly request the guidance of experts! Thank you
Theoretically, it should not affect the octane rating; however, if the mixture is too dry, the vehicle will emit black smoke during combustion.
Perhaps gasoline with a low initial boiling point and a higher content of olefins will have a higher octane rating, but the effect of the dry point is not significant. Dry content and sulfur content. . ? ? Waiting for the marked answer
Theoretically, 80% of the sulfur content is in the heavier components; a higher sulfur content also results in a higher dry point for gasoline.
When the dry point increases, the sulfur content generally rises as well, but this holds true provided that the properties of the raw materials do not change. If the density of the raw materials decreases, then an increase in the dry point has little effect on the sulfur content. Additionally, it is also related to the adjustments made during distillation; the specific relationship needs to be determined by analyzing the operating conditions of the facility as a whole
This post was last edited by mjl25mp6 on 2011-5-2 09:16. Well, guys above, let me try to answer this question! Let’s start with octane rating. As we know, the octane rating of gasoline varies depending on its composition. For RON, the olefin content in gasoline has the greatest impact on it ； For mon, the branching degree of the gasoline component has the greatest impact on it. So, an increase in the gasoline boiling range, or in other words, the dry point, will affect the distribution of PONA in gasoline, which in turn affects changes in the octane rating of gasoline. Simply put, in terms of product separation in a catalytic fractionator, as the dry point increases, the content of olefins in gasoline decreases, as does the content of alkanes and naphthenes; only the content of aromatics increases as the dry point rises. The effects of changes in the proportions of various components on these two octane numbers can be easily compared, but it is more difficult to determine their impact on our RON+MON/2 value. Regarding sulfur in gasoline, its distribution is such that it is present in higher concentrations in heavier grades of gasoline, especially in the components with boiling points above 180 degrees. Reducing the dry point of gasoline can affect the distribution of some of this sulfur, but it comes at the cost of a lower gasoline yield; therefore, we usually opt for posterior refining processes rather than altering the cut points to influence sulfur distribution. By the way, there are devices for separating crude gasoline, but they are used for the selective hydrogenation of the light gasoline components.
For finished gasoline, there is no inherent relationship between its dry point and its octane rating or sulfur content. Dry point is an indicator of the boiling range or volatility of gasoline, and it is related to the heaviness or lightness of the components that make up gasoline. Octane number is an indicator of its anti-knock property, and it is a parameter related to the chemical reaction characteristics of the gasoline components. Sulfur content refers to the amount of sulfur-containing impurities in gasoline. Some components of gasoline may exhibit certain regularities related to their specific properties, but for finished gasoline, such regularities are not apparent depending on the blending components used. Unless one component makes up a large proportion. The typical composition of regular gasoline consists of the following components: straight-run gasoline, catalytic cracked gasoline, reformed gasoline, hydrogenated gasoline, alkylated gasoline, MTBE, etc., which is related to the processing procedures in refineries.
Reply to 7# mjl25mp6 Thank you! Then I’ll ask a more specific question: How does the change in the dry point of gasoline that is not the result of hydrodesulfurization affect its octane rating and sulfur content? (Naphtha and C4 mixture to improve gasoline octane rating)?) Please ask
The use of light hydrocarbons for non-hydrogenation reforming to produce high-octane gasoline is a rather unique technology! OP, where is this device? What scale? I want to go and take a look!
The dry point theory of gasoline has no effect on octane rating; a lower dry point corresponds to a lower sulfur content.