Technology

Process Summary and History

The Bagder bisphenol A (BPA) technology is based on a technology platform originally developed by Shell Chemical Co. for their plant in Texas now owned and operated by Hexion, Inc. The technology produces a high-purity BPA product from phenol and acetone that is suitable for polycarbonate and epoxy resin applications. The process uses ion-exchange resin catalyst, and features proprietary purification technology.

Technology Flow

• In the BPA condensation reactors, phenol and acetone react over an ion-exchange resin catalyst in the presence of a homogeneous promoter and excess phenol, to produce bisphenol A, water and various byproducts. The catalyst system has a long catalyst life.
• The reaction water and the small amount of unreacted acetone are removed from the reactor effluent by distillation. 
• Acetone is recycled to the reactor system. No acetone purge is required with this process.
• The reaction water is sent to the waste recovery system, from which wastewater suitable for biotreatment
  and phenol suitable for recycle to the reaction system are produced.
• The dehydration effluent is concentrated to a BPA level suitable for crystallization. 
• BPA is separated from byproducts in a proprietary solvent crystallization and recovery system to produce the adduct of p,p-BPA and phenol.
• Mother liquor from the purification system is distilled in the solvent recovery section to recover dissolved solvent.
• The solvent-free mother liquor stream is recycled to the reaction system. A purge from the mother liquor is sent to the waste recovery system.
• The purified adduct is processed in a BPA finishing system to remove phenol from the product.
• The resulting molten BPA is solidified in the prill tower to produce prills suitable for the merchant BPA market, including polycarbonate production. 

 Commercial Experience

• 21 licensed BPA plants in commercial operation with installed capacity of over 3.9 million tpy 
• Single train plant capacities of 60,000 tpy – 240,000 tpy 
• Technology reference plant operating since 1992 
• 98% demonstrated on-stream factor 

References

1. Bader > Technologies > Technologies overview > Bisphenol A (BPA) (Accessed 17^th Jun 2025)