The invention provides a low-cost preparation process for synthesizing
phenylethyl resorcinol, which comprises the following steps: taking
styrene and
resorcinol as raw materials, taking strong-acid
styrene cation exchange resin as a catalyst, and reacting at the temperature of 60-80 DEG C to obtain the
phenylethyl resorcinol. The method comprises the following steps: carrying out a Friedel-Crafts
alkylation reaction in a single
solvent to obtain
phenylethyl resorcinol, separating a reaction solution from a catalyst, introducing the obtained reaction
mother liquor into continuous extraction equipment, adding water, carrying out continuous extraction, concentrating the extracted
mother liquor, and purifying to obtain the phenylethyl
resorcinol. The recrystallization step comprises the following steps: adding a single
solvent into the concentrated
mother liquor for dissolving, crystallizing and
drying to obtain purified phenethyl
resorcinol, concentrating and crystallizing the mother liquor, and recycling the
solvent. Wherein the recovered solvent in the extraction and recrystallization steps is circularly applied to the
reaction step and the recrystallization step. According to the method, a
solid resin catalyst with lower cost is used, continuous extraction equipment is introduced, so that the
wastewater treatment cost is lower, the preparation process cost is further saved due to solvent application, and the whole process disclosed by the invention not only meets the requirements of the market on high-purity finished products, but also has important significance on large-scale synthesis and production
cost control.