What Is Naphtha? Properties, Functions, & How to Process It

When it comes to refined petroleum products, you might also hear about naphtha. Naphtha is a general term to describe petroleum products, either the purified or unpurified ones. This article discusses naphtha, including its types, functions, and how to process it. Thus, read this article until the end!

What Is Naphtha?

Naphtha is a hydrocarbon liquid processed from crude oil. This product belongs to organic compounds and is frequently called crude oil distillate. According to the Pipeline Rules of Thumb Handbook, naphtha fills about 15–30% of crude oil weight.

Naphtha is an important feedstock in the petrochemical industry because it is used to produce chemicals, such as butadiene, ethylene, and propylene.

After that, those chemicals will be used for manufacturing consumer products, such as solvents, fuels, plastics, rubbers, and many more. Since it is a crucial feedstock, the world demand for petroleum is predicted to increase in 2025.

Data on Statista forecasts that in 2025, global oil demand will reach 105 million barrels per day. Typically, naphtha is desulfurized and made with a catalyst to produce high-octane naphtha. Then, it is mixed with other components to make gasoline.

Naphtha can be manufactured with several methods, such as distillation, fractionation, solvent extraction, hydrogenation cracking, olefin polymerization, and alkylation. Yet, naphtha can be produced using mixed substances from various processes.

The Properties of Naphtha

Naphtha has certain properties that make it distinct from other fractions, such as:

Volatile: Naphtha is a volatile fraction. It is often used to increase the octane rating of gasoline in the catalytic reforming process.
Hydrocarbon composition: Naphtha has 5–12 carbon atoms and consists of a mixture of aromatic, naphthenic, and aliphatic hydrocarbons. Light naphtha has 5–6 carbon atoms, while heavy naphtha has 6–12 carbon atoms.
Flammability: This material is very flammable, making it the main component of fuel oil production, such as gasoline and kerosene.
Colorless: It is colorless but can also be reddish-brown like gasoline.
Typical odor: It has a typical hydrocarbon or gasoline-like smell.
Various boiling points: The boiling point of naphtha ranges from 30 to 200 degrees Celsius. Light naphtha has a boiling point of about 30–90 degrees Celsius, while heavy naphtha has a boiling point of about 90–200 degrees Celsius.

Types of Naphtha

Naphtha is divided into three main grades: light, heavy, and aromatic naphthas. Here is the complete explanation of each type:

1. Light Naphtha

Light naphtha, or paraffinic naphtha, is a paraffinic hydrocarbon-rich naphtha. It is usually used for making petrochemical feedstocks, such as propylene and ethylene.

Light naphtha has a boiling point of 30–90 degrees Celsius and contains 5–6 carbon atoms. Typically, light naphtha is utilized for making fuels, like gasoline, coatings, solvents, and paints.

2. Heavy Naphtha

Heavy naphtha, or naphthenic naphtha, is a crude oil fraction having a boiling point of 90–200 degrees Celsius. Generally, it contains cycloalkane and alkane. Yet, some of this naphtha also contains aromatics.

This naphtha has a low Research Octane Number (RON), so it needs to be processed to increase its content. The general property of heavy naphtha is that it is highly volatile. This material is usually used to make engine oil, solvents, and asphalt.

3. Aromatic Naphtha

Aromatic naphtha contains many aromatic components. It can be smoky, carcinogenic, and toxic. Aromatic naphtha is suitable for producing industrial liquid solvents, fuel additives, paints and coatings, pesticides, household cleaners, etc.

The Functions of Naphtha

As mentioned before, naphtha is one of the important feedstocks in the manufacturing process. The functions of naphtha are as follows:

1. Petrochemical Industry Feedstocks

Naphtha is frequently used to make propylene, butadiene, and ethylene, which are later used to produce synthetic materials, such as plastics and rubbers.

2. Gasoline Materials

Through catalytic reforming, naphtha is processed into gasoline fuel and increases its octane content. Catalytic reforming is the process of converting low-octane naphtha into high-octane gasoline components called reformate. In this process, several reactions occur, such as polymerization, isomerization, cracking, and dehydrogenation.

3. Industrial Solvent Materials

Naphtha is used to make adhesives, solvents, coatings, inks, and paints as an organic solvent. Naphtha has the property of dissolving chemicals.

4. Steam Reforming Feedstocks

Naphtha is utilized to create hydrogen in the steam reforming process. The hydrogen is then used to purify crude oil and produce ammonia.

How to Process Crude Oil into Naphtha

Crude oil undergoes a series of processes, from distillation to blending. Here is how crude oil is processed into naphtha:

1. Distillation

Distillation will break down hydrocarbon compounds in crude oil at high temperature and pressure. Then, petroleum fractions will be formed according to their boiling points. The lightest fraction is propane, and the heaviest fraction is bitumen.

2. Cracking

Cracking is a process of breaking down the larger hydrocarbons into smaller ones. This process is also called refining. Some common cracking methods are fluid catalytic cracking, thermal cracking, hydrocracking, and catalytic cracking.

3. Reforming

This process increases the product quality with the support of pressure, a catalyst, and heat. Reforming creates isoparaffins and aromatics to blend high-octane gasoline.

4. Polymerization

In the polymerization process, light unsaturated hydrocarbons will react and form larger molecules. One example of petroleum polymerization is the reaction of butene to isobutane to make polymer gasoline.

5. Alkylation

Alkylation combines olefin and isobutane to create isoparaffin. It is then used to increase the octane rating of gasoline. The final product of alkylation is called alkylate.

6. Treating

Treating is the process of refining the fraction by removing contaminants, such as sludge, sulfur, and paraffin, as well as unpleasant odors. As a result, the treated naphtha has a standardized quality.

7. Blending

Blending improves the quality of products with additives. One of the active ingredients added to petroleum products is tetraethyl lead, which can increase the octane rating of gasoline. Consequently, petroleum products are ready to be distributed and utilized as industrial feedstocks.

That concludes the information about naphtha. This chemical is important for various manufacturing processes, like synthetic material production. Regarding industrial chemicals, Chandra Asri Group can be the solution!

Chandra Asri Group is a prominent chemical solution company in Southeast Asia, providing various industrial chemicals, such as polypropylene, polyethylene, butadiene, styrene monomer, and many more.

So, to produce quality consumer products, make sure to use standardized chemicals from Chandra Asri Group!