Low Color BEHFD Plasticizer via Catalytic Hydrogenation

The patent introduces a hydrogenation catalyst as an intermediary substance that mediates between the colored BEHFD product and hydrogen gas. The catalyst (such as Pd/C, PtO2, or Raney nickel) facilitates the hydrogenation reaction that removes color-causing conjugated double bonds, transforming the harmful colored product into a desirable low-color or colorless product while maintaining the esterification pathway's simplicity

The patent changes the chemical parameters of the BEHFD molecule by adding hydrogen across conjugated double bonds through catalytic hydrogenation. This parameter change (reducing the degree of unsaturation) directly addresses the color issue by eliminating the chromophores responsible for high APHA values, while the reaction conditions (temperature, pressure, catalyst loading) are optimized to maintain process simplicity

The patent applies preliminary hydrogenation action during or immediately after the esterification process. By introducing the hydrogenation step early in the synthesis sequence (either concurrently with esterification or as a brief subsequent step), the color reduction is achieved before the product undergoes further processing, thereby minimizing the overall process complexity while ensuring low-color output

The hydrogenation catalyst serves as a temporary intermediary that is introduced only when needed for color reduction and can be easily removed or deactivated afterward. This allows the process to remain relatively simple, as the catalyst can be filtered off or deactivated without requiring complex separation equipment or additional processing steps