The invention discloses a refining method for preparing high-purity natural
benzaldehyde from bitter
apricot kernel essential oil, and relates to the technical field of
benzaldehyde refining, the bitter
apricot kernel essential oil and a
sodium propionate-
acetic acid buffer solution with the pH value of 5.5 + / -0.2 are hydrolyzed for 30-35 min through an immobilized beta-
glucosidase reactor at the flow rate of 0.8-1.2 mL / min and at the temperature of 40 + / -2 DEG C; directly introducing a reactor outlet product into a PDMS membrane
permeation unit, and continuously separating
benzaldehyde; cooling and condensing the
permeation steam through a two-stage condenser, filtering the obtained liquid concentrate through a 0.2 mu m micropore, feeding the filtered liquid concentrate into a
solid-phase adsorption column filled with molecular MIP, and eluting with
ethanol and water; removing
ethanol from the MIP eluent, introducing the MIP eluent into an SMB chromatographic
system, and realizing continuous extraction of benzaldehyde with the purity of more than or equal to 99.5% and the yield of more than or equal to 85% by using a water-
ethanol mobile phase. According to the method, the immobilized beta-
glucosidase is combined with online degassing, so that online efficient
hydrolysis of cyanoglycoside and safe degradation of
cyanide are realized, the problems that thermal degradation is serious in traditional
distillation and
cyanide is difficult to remove in conventional extraction are solved,
cyanide residues are effectively eliminated, and the product is safe and environment-friendly.