TH31492A - Process for the continuous production of dihydroxidioryl alkane - Google Patents

Abstract

DC60 (21/05/41) This invention relates to a process for the continuous production of dihydroxydiaryl alkane (bisphenol) by reaction of fresh phenol, phenol and isoalkenylphenol from the decomposition of by-products and ketones. In this process, the amount of bisphenol recovered from the reaction mixture by crystallization and the materialic warp obtained is freed from phenol by distillation. Phenol is reintroduced into the reaction, and the residue obtained during distillation is decomposed by adjusting the reaction activity after the addition of a basic catalyst. The phenol and isoalkenylphenol released at the peak are reintroduced into the reaction. The residue from the first active column is acidified, and by adjusting the reaction activity a second time in the presence of an acidic catalyst, it is further decomposed into phenol, which is distilled out and reintroduced into the reaction, and the residue is discarded. This invention relates to a process for the continuous production of dihydroxydiarylalkane (bisphenol) by reaction of peak phenol, phenol and isoalkenylphenol from the decomposition of by-products and ketones. In this process, a quantity of bisphenol is recovered from the reaction mixture by crystallization, and the resulting materialic warp is freed from phenol by distillation, reintroducing phenol into the reaction, and the residue obtained during distillation is decomposed by adjusting the reaction activity after the addition of a basic catalyst. The peak phenol and isoalkenylphenol are reintroduced into the reaction. The residue from the first active column is acidified, and by adjusting the reaction activity a second time in the presence of an acidic catalyst, it is further decomposed into phenol, which is distilled out and reintroduced in the reaction, discarding the residue.

Claims (7)

The process for the sustained production of hydroxydiaryl alkane (bisphenol) from ketones, phenols, and isoalkenyl phenols by catalyst using a specific acid. 1. In a series of at least two reactors, phenols react with ketones and isoalkenylphenols in such a way that the reaction is carried out at the lowest possible temperature, but at an increasing temperature in the direction of the reaction progression, and acetone and isoalkenylphenols are shared between the two reactors. 2. Unreactive ketones are distilled from the mixture, and the acidic components present in the reaction mixture are selectively removed. 3. The majority of bisphenols were separated from the reaction mixture by crystallization. 4. Combine the obtained mother liqueur with the washed phenol. Distill this phenol and return it to the reaction. 5. The bottom-dwelling compounds containing bisphenol, various isomers, and by-products are decomposed in the presence of a catalytic amount of base to adjust the reaction rate correctly, into phenols and isoalkenyl phenols, which are released at the top and leave a high-boiling residue at the bottom. 6. The remaining high-boiling point residue at the bottom is acidified to provide an acid-catalyzing concentration, causing it to decompose further into phenol and then into a final residue that must be discarded. 7. Selectable phenolic distillates from 6 and phenolic distillates/isoalkenylphenols from 5, after further purification, were returned to the reaction to produce phenols (Clause 7, page 1, figure 1).