Study on the synthesis of bisphenol S by reactive dehydration in rotating packed bed

In this work, the synthesis of bisphenol S (4,4′-BPS) using reactive dehydration in a rotating packed bed (RPB) was studied. Firstly, orthogonal experiments were adopted to investigate the effects of different operating conditions on the yield and content of 4,4′-BPS in a stirred tank reactor (STR), including the mesitylene/phenol molar ratio ( μ ), reflux dehydration time ( t ), and stirring speed ( n ), in order to optimize the operating conditions in STR. Based on the study in STR, the effects of operating conditions, including rotation speed ( N ), feeding rate ( q ), and cycle number ( τ ), on the yield and content of 4,4′-BPS in RPB combined with STR (RPB-STR) were further investigated to optimize the operating conditions. The results indicated that compared to STR, the yield and content of 4,4′-BPS increased by 22.1% and 7.52% under the optimal operating conditions in RPB-STR, respectively. This work provides a novel route for efficient synthesizing 4,4′-BPS.