Abstract:

Transformation of disodium 2,6-naphthalenedisulfonate into 2,6-naphthalenedisulfonic acid was catalyzed by cationic exchange resin and the 2,6-naphthalenedisulfonic acid was used to catalyze the synthesis of bisphenol S(BPS). The effects of the reaction time, temperature and the amount of resin were investigated. The optimized exchange process was applied as follows:After disodium 2,6-naphthalenedisulfonate was completely dissolved, 37 times of 001×7 strong acidic polystyrene type cationic exchange resin were added into the system. The converted products were used to catalyze the synthesis of BPS. The yield of crude product BPS reached 93.5% and the mass fraction of BPS was 92.3%. Crude BPS was purified by adsorbent without organic solvent. The mass fraction of the product obtained by the process is high. The improved process is easy to be operated and industrialized. The improved purification process was applied as follows:Firstly 7 g of crude BPS was dissolved in 300 g hot water. Then 0.5 g sepiolite and 0.2 g active carbon were added under stirring. The wet product was dissolved in 180 g hot water again and another 0.3 g sepiolite was added. After 1 hour of stirring, a white product was obtained and the purity of BPS reached 99.7%. The water could be recycled, resulting in increasing yield of product BPS to 82.9% at the same time.

Key words: bisphenol S, disodium naphthalenedisulfonate, cationic exchange resin, purification, adsorbent