Method for recovering sodium hydroxide during p-cresol sulfonation and alkali fusion

The invention relates to a method for recovering sodium hydroxide during p-cresol sulfonation and alkali fusion. According to the method, an alkali fusion reaction material is taken as a raw material,after an alkali fusion reaction, water is added in a product obtained by the alkali fusion reaction, the materials are uniformly stirred, sodium sulfite is filtered while hot, a filtrate is subjectedto twice filtering, and a filter cake p-sodium cresylate and a filtrate sodium hydroxide aqueous solution are finally obtained. The difference and characteristic of solubility of sodium sulfite and p-sodium cresylate in the sodium hydroxide aqueous solution are used, by adjusting alkali concentration, sodium sulfite and p-sodium cresylate are filtered in order, the filtrate with sodium hydroxidedesolvation concentration being 25% is obtained, and the sodium hydroxide recovery rate is 79%. The method for recovering sodium hydroxide can effectively recover the sodium hydroxide during a p-cresol production process by a s