Petroleum Gases and Gas Hydrates

Name: Petroleum Gases and Gas Hydrates
Author: KnowledgeCity

Explore the differences between naturally occurring gases, created gases, and clathrates

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Course: On-Demand

Let's apply concepts of physical and chemical properties to petrochemicals, as we move on to petroleum gases. Hydrocarbon gases are the carbon and hydrogen-based petroleum products that end up as gases at room temperature, or may be dissolved in crude oil due to pressure. We've discussed the main hydrocarbons used for fuel, heating and other commercial uses, methane, ethane, propane and butane. These are naturally occurring gases in petroleum deposits. Gases processed from refineries include ethylene, propylene and butylene. Now let's look at the physical and chemical properties of hydrocarbon gases together. Methane is the smallest natural gas and butane is the largest in this series. Ethylene is the smallest unsaturated hydrocarbon gas and butylene or 1-butene for this comparison, is the largest. If you notice the physical properties trends illustrated in the table, you'll see that the melting points don't vary much, say for butane and ethylene, that's because the change in phase from solid to liquid doesn't vary much across different hydrocarbons. However, if you look at boiling points, you'll notice that they increase as the number of carbons increases. Likewise, as the number of carbons increases, the molecular weight increases in direct proportion. You'll also notice that the specific gravity increases as the size of the molecule increases. Critical temperature follows this same upward trend, but the differences are more dramatic. These points are all dependent on the individual equilibrium curves of each compound. Critical pressure is a little different. Much like melting point, it doesn't exhibit the same trends depending on individual pressure equilibrium curve data. These are just examples of what we can tell about hydrocarbon gases from their physical properties. Let's look at what their chemical properties can tell us. In this table, you'll notice that as the size of the molecule increases in the natural gas, the heat of combustion goes up. This makes sense since the energy released due to combustion increases with size and there's more to combust. The alkenes are slightly different. Ethylene and propylene have negative heats of combustion, which means these are endothermic reactions that don't give off heat due to combustion. Endothermic means the reaction requires energy to form carbon dioxide and water. Butylene or 1-butene is the only one of those hydrocarbon alkene gases that is exothermic. The enthalpy of formation ends up being the opposite sign of the heat of combustion. For instance, with methane, the heat of combustion is a positive value because energy is released when ignited, however enthalpy is negative, because the heat is released from the system due to the reaction. Ethylene is the opposite. In the reverse direction, ethylene can be hydrogenated into ethane and create an exothermic reaction. The formation ethylene requires energy instead of releasing it, so it's positive. Other than these trends in chemical properties, all hydrocarbon gases have a flammability rating of four, which means they all rapidly vaporize and ignite in ambient conditions.

Essential Provider : KnowledgeCity 5 Lessons · 19m in Arabic, English

Course Description

In this course on Petroleum Gases, we will discuss the properties of petroleum gases, gases that are naturally occurring, and those created by the refining process.

We will look at both hydrocarbon gases and non-hydrocarbon gases. Each type of petroleum gas has a variety of uses and applications that will be examined. We will look at those uses and the economic impact of each of those gases as well as the environmental impact of the petroleum gases. With hydrocarbon gases we will learn about naturally occurring gases, such as methane, propane, and butane, as well as those gases that occur due to the refining process. For each of the gases discussed we will examine physical properties and the chemical properties. We will also examine the physical and chemical properties of non-hydrocarbon gases. We will discuss hydrogen sulfide and learn what sour gas is, and we will spend part of our time learning about carbon dioxide and helium among other gases.

What You'll Learn

Analyze the chemical properties of petroleum gases
Understand the physical properties of petroleum gases
Examine how the refining process creates petroleum gases
Distinguish between hydrocarbon and non-hydrocarbon gases
Learn about hydrogen sulfide, sour gas, carbon dioxide, and helium
Evaluate the economic and environmental impact of petroleum gases

Key Takeaways

Petroleum gases include both naturally occurring gases and gases created by the refining process.
Hydrocarbon gases covered include methane, propane, and butane, while non-hydrocarbon gases include hydrogen sulfide, carbon dioxide, and helium.
Each type of petroleum gas has a variety of uses and applications, along with distinct economic and environmental impacts.
The course examines both the physical and chemical properties of hydrocarbon and non-hydrocarbon gases.
Sour gas is associated with hydrogen sulfide, which is explored as part of the non-hydrocarbon gases.

Frequently Asked Questions

What does this course cover?

It covers the properties of petroleum gases, including naturally occurring gases and those created by the refining process, looking at both hydrocarbon gases (such as methane, propane, and butane) and non-hydrocarbon gases (such as hydrogen sulfide, carbon dioxide, and helium), along with their uses, applications, and economic and environmental impact.

What topics are included in the lessons?

The lessons cover Hydrocarbon Gases, Non-Hydrocarbon Gases, Occurrence and Composition, Identification, and Economic Significance.

What is sour gas in this course?

The course discusses hydrogen sulfide and explains what sour gas is as part of its coverage of non-hydrocarbon gases.

What skills does this course relate to?

It relates to Liquefied Petroleum Gas, Natural Gas, Petroleum Engineering, Petroleums, Petroleum Geology, and Petroleum Engineering Certification.

Does the course cover the environmental impact of petroleum gases?

Yes, the course examines the environmental impact of the petroleum gases as well as the economic impact of each of the gases discussed.