Preparation and Primary Applications of High-Purity Ethylene

High-purity ethylene is a gas with a purity of over 99.9% and serves as a crucial raw material in the industrial and scientific fields. It finds extensive applications in industries such as plastics, chemicals, and rubber, while also playing a significant role in the electronics industry. This article will introduce the preparation methods and primary applications of high-purity ethylene.

Ⅰ.Preparation of High-Purity Ethylene

The preparation of high-purity ethylene is primarily achieved through the cracking process of aliphatic hydrocarbon compounds found in petroleum or natural gas. Cracking is a chemical reaction that breaks long-chain hydrocarbon molecules into shorter-chain hydrocarbons. There are two main methods for preparing high-purity ethylene, namely thermal cracking and steam cracking. Below, we will provide separate explanations for these two methods.

1.Thermal Cracking Method

The cracking reaction is as follows: CnH2n+2 → n C2H4

The thermal cracking method typically employs aliphatic hydrocarbon compounds found in petroleum or natural gas as raw materials. The main components are hydrocarbons with longer aliphatic chains, such as propane (C3H8) and butane (C4H10). These raw materials are usually extracted and purified through petroleum refineries or natural gas processing plants to ensure their quality and purity.

In a high-temperature and high-pressure environment, the aliphatic hydrocarbon compounds in the raw materials undergo a cracking reaction, breaking the long-chain aliphatic hydrocarbon molecules into short-chain olefin molecules, such as ethylene. In this reaction, each aliphatic hydrocarbon with n carbon atoms is cracked into n ethylene molecules.

The ethylene gas produced by the cracking reaction typically contains impurities, such as other hydrocarbons and trace gases. Therefore, it is crucial to separate and purify the generated gas. Various processes, including condensation, adsorption, and scrubbing, are commonly employed to remove impurities and enhance the purity of ethylene. At this stage, the collected ethylene gas needs to undergo analysis and testing to ensure its purity meets the required standards, typically demanding a purity level of 99.9% or higher for high-purity ethylene.

2.Steam Cracking Method

The steam cracking method is relatively simple, efficient, and suitable for large-scale industrial production, making it widely utilized in various industries. This method can efficiently convert aliphatic hydrocarbon compounds found in petroleum or natural gas into high-purity ethylene gas, making it a crucial raw material in many industries.

The raw materials typically used in the steam cracking method are petroleum or natural gas. These raw materials are usually light petroleum fractions or natural gas containing aliphatic hydrocarbon compounds such as propane and butane. Prior to the cracking reaction, these raw materials undergo processing and purification to ensure their quality and purity, preventing any impurities that may adversely affect the cracking process.

Subsequently, under high-temperature and high-pressure conditions (typically maintaining temperatures within the reactor between 750°C to 850°C), the aliphatic hydrocarbon compounds in the raw materials react with water vapor to undergo cracking. This results in the breaking of long-chain aliphatic hydrocarbon molecules into short-chain olefin molecules, with ethylene being the primary product. The ethylene gas produced by the cracking reaction is usually accompanied by other hydrocarbons and impurities.

Therefore, it is essential to separate and purify the obtained gas using processes such as condensation, adsorption, and scrubbing to remove impurities and enhance the purity of ethylene.

Ⅱ. Application

High-purity ethylene, as an important industrial raw material, finds widespread applications in various fields such as chemical, plastics, electronics, pharmaceuticals, and food industries. Different industries have varying requirements for ethylene, and high-purity ethylene is particularly used extensively in the production of semiconductors and optical materials.

1.Polyethylene Production

High-purity ethylene serves as a primary raw material for polyethylene (PE) production. Polyethylene, a versatile plastic, is widely utilized in packaging materials, containers, plastic bags, bottles, and more. Through polymerization reactions, high-purity ethylene is transformed into different types of polyethylene, such as high-density polyethylene (HDPE) and low-density polyethylene (LDPE). Due to its lightweight, durability, ease of processing, and cost-effectiveness, polyethylene has gained widespread popularity in various everyday applications.

2.Semiconductor Manufacturing

High-purity ethylene plays a crucial role in the semiconductor industry. Specifically, it is used as a special gas during the Metal Organic Chemical Vapor Deposition (MOCVD) process. In MOCVD, high-purity ethylene acts as a carbon source for growing materials like Gallium Nitride (GaN). GaN is extensively employed in the production of optoelectronic devices, lasers, and high-power amplifiers, among others. The application of high-purity ethylene in semiconductor manufacturing contributes to enhanced device performance and quality.

3.Optics Device Fabrication

In optics device manufacturing, high-purity ethylene serves as a doping gas. Introducing high-purity ethylene into specific materials allows for the modification of their optical properties, enabling targeted functionalities. For instance, in fiber optics production, doping with high-purity ethylene alters the refractive index, leading to different transmission characteristics. The application of high-purity ethylene in lasers and fiber optic communications facilitates the creation of more efficient and high-performance devices.

Ⅲ.Summary

High-purity ethylene gas plays a vital role as an essential industrial material, contributing significantly to various fields and providing critical support for development and innovation. Goldhong Gas Co., Ltd. has been specializing in the gas supply industry for many years, serving over 500 overseas clients, and offering various ethylene supply solutions. If needed, feel free to contact our company. With ongoing technological advancements, the application prospects for high-purity ethylene will continue to expand, bringing about further development and possibilities for society.