Method for separating and purifying L-serine from fermentation liquor

The invention discloses a method for separating and purifying L-serine from fermentation liquor. The method comprises the following steps: (1) diluting the fermentation liquor containing the L-serine with pure water until the concentration of the L-serine is less than or equal to 10 g/L, adjusting the pH value to 3.5-4.0, then filtering with a ceramic membrane, and collecting filtrate; (2) concentrating the filtrate until the concentration of L-serine is 400-450 g/L to obtain a concentrated solution; (3) carrying out plate frame decolorization on the concentrated solution to obtain a decolorized solution; (4) treating the decolorized solution through cation exchange resin and anion exchange resin in sequence to obtain a purified solution; and (5) carrying out centrifugal crystallization on the purified solution, collecting crystals, washing, drying, and separating and purifying to obtain the L-serine. According to the method for separating and purifying the L-serine, industrial production can be realized, and