Natural Gas and Polymers: Properties, Uses, and Impacts
Natural Gas: Properties, Uses, and Impacts
Natural gas is a mixture of hydrocarbons with a high proportion of methane, often found in oil fields. The methane content in natural gas typically ranges from 75 to 95% of the total volume, hence it’s often called methane gas. Other components include ethane, propane, butane, nitrogen, carbon dioxide, hydrogen sulfide, helium, and argon.
Key Characteristics of Natural Gas
- It is between 35 to 40% lighter than air.
- It is tasteless, colorless, and odorless.
- It is non-toxic.
- It has relatively low flammability.
- It generates relatively clean combustion.
- Liquefaction point: -161°C.
- Calorific value: Complete combustion of one cubic meter of natural gas generates about 9,300 kilocalories.
Importance of Natural Gas
Natural gas is used as domestic and industrial fuel. Besides its high calorific value and controlled combustion that produces little pollution, it’s also used as feedstock in the petrochemical industry to obtain ammonia, methanol, ethylene, propylene, and butadiene.
Environmental Impact
Exploration wells are often located in diverse ecosystems. The process uses a lot of water to cool the drill, which is then deposited in contaminated wells, potentially reaching rivers and the sea. Oil transportation can lead to accidents and spills, especially in water bodies, altering marine ecosystems.
Economic Impact
The exploitation of oil and natural gas has replaced wood and coal as primary energy sources. However, the uneven distribution of oil on the planet has created economic disparities between countries.
Polymers: Types and Applications
A polymer is a substance whose molecules are multiples of low molecular weight units called monomers.
Common Polymers
Polyethylene (PE)
Polyethylene is chemically the simplest polymer, represented by its repeating unit (CH2-CH2)n. Due to its high global production, it is one of the cheapest and most common plastics. It is chemically inert and produced from the polymerization of ethylene.
Polypropylene (PP)
Polypropylene is a partially crystalline thermoplastic obtained from the polymerization of propylene (or propene). It is used in a wide variety of applications, including food packaging, textiles, laboratory equipment, automotive components, and transparent films.
Polystyrene (PS)
Polystyrene (PS) is a thermoplastic polymer obtained from the polymerization of styrene. There are four main types:
- Glass PS: Transparent, rigid, and brittle.
- High-impact polystyrene: Strong and opaque.
- Polystyrene foam: Very lightweight.
- Extruded polystyrene: Expanded, similar to foam but more dense and waterproof.
Polyurethane (PU)
Polyurethane is a polymer obtained by the condensation of polyols with polyisocyanates. It is divided into two groups: thermosetting and thermoplastic (thermoplastic polyurethane).
Polyvinyl Chloride (PVC)
Polyvinyl chloride (PVC) is a thermoplastic polymer that appears as a white material. It begins to soften around 80°C and decomposes above 140°C. It is both a polymer and a resin resulting from the polymerization of vinyl chloride or chloroethylene.