Aqueous phenolic resin, known for its excellent heat resistance, adhesion, and mechanical strength, is widely used in coatings, adhesives, friction materials and composite materials. One long-standing challenge in its production and application is the effective removal of unreacted free phenol. This issue not only affects product quality and stability but is also directly related to environmental compliance and end-user safety.
Traditional methods such as water washing, adsorption, or vacuum dephenolization often suffer from low efficiency, high energy consumption, secondary pollution, or inability to support continuous production, making them inadequate for the modern chemical industry’s demands for both efficiency and environmental protection.
In response to increasingly stringent environmental regulations and market expectations, Zhengzhou Tiei Extraction Technology Co., Ltd. has introduced the CWL-M series centrifugal extractor, offering a high-efficiency, continuous, and safe solution.
Process Principle: Isooctanol Extraction--Efficient Separation
Liquid-liquid extraction technology is a proven and efficient method for removing free phenol. The key lies in selecting a suitable extractant that can efficiently dissolve phenol while being immiscible with the aqueous phase (resin solution) and easily separated.
Isooctanol is precisely such an ideal extractant:
- High selectivity: Isooctanol has a very high distribution coefficient for phenol, allowing it to preferentially “capture” phenol from the aqueous phase.
- Low solubility: Its extremely low solubility in water prevents significant loss of extractant into the aqueous phase, avoiding contamination of the resin.
- Easy separation: Isooctanol and water have a large density difference and form a clear interface, enabling convenient downstream phase separation.
CWL-M Centrifugal Extraction Process
The aqueous phenolic resin solution containing free phenol is fed into the centrifugal extractor together with isooctanol at a specific ratio to ensure thorough contact. Phenol rapidly transfers from the aqueous resin phase into the isooctanol phase. After phase separation, a purified resin solution and a phenol-rich isooctanol phase are obtained. The phenol-loaded isooctanol can be subjected to alkaline back-extraction to recover the phenol, allowing the isooctanol to be reused. The entire process is both environmentally friendly and economically efficient.
Core Equipment: Why Is the CWL-M Centrifugal Extractor the Optimal Choice for This Process?
Although the process principle is straightforward, the success of its implementation depends critically on the equipment. Traditional mixer-settlers or extraction columns often encounter issues in this application, including poor mixing, incomplete separation, easy emulsification, and large holdup (leading to resin retention and product loss). The Tiei Extraction CWL-M centrifugal extractor solves these problems inherently through its design.
1.Instantaneous Mixing & High-Speed Separation
The CWL-M uses a high-speed rotating drum to achieve extremely fine mixing between isooctanol and the resin solution within a very short time, resulting in exceptionally high mass-transfer efficiency.
Subsequently, under a centrifugal field thousands of times stronger than gravity, the two phases are rapidly and thoroughly separated due to their density difference. This effectively prevents emulsification and ensures the purity of both the resin phase and the extractant phase.
2.Ultra-Short Residence Time & Minimal Holdup
The materials remain inside the equipment for only a few seconds, avoiding potential changes in resin properties or emulsification that may occur with prolonged contact.
The internal liquid holdup is extremely small, minimizing resin retention and loss within the system, thereby directly improving yield and economic performance.
3.Continuous, Automated, and Fully Enclosed Operation
The CWL-M supports continuous and stable 24/7 operation, integrating seamlessly with existing production lines and significantly increasing throughput.
Its fully sealed design effectively prevents the volatilization of phenol and isooctanol, greatly improving the working environment and ensuring operator health and production safety.
Email: sales@tieiextraction.com
Whatsapp: +86 19069612820
