Carbon fiber materials are gaining popularity due to their wide range of applications in aerospace, automotive, rail transportation, high-end medical devices and sports equipment. Its high-strength properties have brought new hope for development in many industries. Carbon fiber can be categorized into petroleum-based and bio-based types. At present, petroleum-based carbon fiber has superior performance and higher production volume than bio-based carbon fiber, but the latter still has significant potential.
Petroleum-based carbon fiber dominates the market
Petroleum-based carbon fiber products are currently the market leaders. These include polyacrylonitrile (PAN) - based, pitch - based and viscose - based carbon fibers. PAN-based carbon fibers account for over 90% of total carbon fiber production, pitch-based fibers account for approximately 7%, and viscose-based fibers account for approximately 1%. This difference is mainly due to differences in performance and processing difficulty. PAN-based carbon fiber is the dominant product in the market and the cornerstone of petroleum-based carbon fiber's market position.
Carbon fiber is an amazing thin filament made of almost pure carbon crystals with a diameter of 5 - 10 micrometers. It has five times the mechanical strength and twice the hardness of steel. Carbon fiber was originally made from plant-based materials such as cellulose and rayon, but was later replaced by petroleum-based products due to their lower cost and better performance.
To make carbon fiber, petroleum is first processed into highly toxic PAN. It is drawn into fine filaments and then heated in oxygen-free furnaces. However, this production process consumes considerable energy and generates numerous emissions and toxins. Unlike in the past when cost was the primary concern, sustainability is now more critical and petroleum is no longer as cheap.
Why develop bio-based carbon fiber?
Compared to PAN-based fibers, bio-based carbon fiber has mid- to low-end performance. So why develop it? This requires understanding the drawbacks of petroleum - based carbon fiber.
Petroleum-based carbon fiber production is energy intensive, produces harmful substances, and harms the environment. In addition, carbon fiber products are difficult to recycle, resulting in high production costs and post-processing difficulties. To reduce production costs and dependence on fossil raw materials, research on bio-based carbon fiber precursors is gaining attention. For example, lignin, glycerin and lignocellulosic sugars are being explored as alternative raw materials.
Environmental protection is a pressing global issue and a consensus among all countries. Although carbon fiber materials have obvious advantages, they are not environmentally friendly. Therefore, scientists are seeking solutions, and "carbon neutrality" has become a driving force for the development of bio-based carbon fiber. Petroleum-based carbon fiber cannot replace bio-based carbon fiber, and in the future, both types will develop in parallel. The key is which direction will see greater breakthroughs and achievements.
