Synthesis of bisphenol-F using sulfonic functionalized SBA-15 as catalyst

Abstract

Sulfonic functionalized SBA-15 catalysts, SBA-15-Pr-SO3H and SBA-15-Ar-SO3H, were synthesized by direct synthesis under acidic condition using triblock P123 (poly(ethylene oxide)20–poly(propylene oxide)70–poly(ethylene oxide)20) copolymer as a structure directing agent. The gel composition of SBA-15-Pr-SO3H was 0.0369 TEOS: 0.0041 MPTMS: 0.0369 H2O2: 0.24 HCl: 6.9046 H2O: 0.0007 P123. In addition, the gel composition of SBA-15-Ar-SO3H was 0.0369 TEOS: 0.0041 CSPETMS: 0.0369 H2O2: 0.24 HCl: 6.9046 H2O: 0.0007 P123. The synthesized materials were characterized by X-ray powder diffraction, nitrogen sorption analysis, sulfur elemental analysis, solid state 13C-MAS-NMR and scanning electron microscopy. Catalytic performances of SBA-15-Pr-SO3H and SBA-15-Ar-SO3H were studied in catalyzing the phenol with formaldehyde to form bisphenol-F under different conditions. The optimum condition on bisphenol-F preparation was phenol to formaldehyde molar ratio of 30 mol mol-1, catalyst to formaldehyde weight ratio of 15 wt% at 90°C for 1 h under the absence of solvent. Furthermore, catalytic activity of the synthesized catalyst was compared with other catalysts such as ion-exchanged resins, zeolites and Al-mesoporous materials. Among various heterogeneous catalysts, SBA-15-Pr-SO3H exhibited high catalytic activity due to giving high bisphenol-F yield of 98% and selective to 4,4'-isomer. Moreover, the regenerated catalyst revealed similar activity and performed the product isomer distribution closing to the fresh one. Thus, SBA-15-Pr-SO3H catalyst was able to be an efficient catalyst for bisphenol-F preparation.