FIELD: technological processes.
SUBSTANCE: present invention relates to a method of inhibiting undesirable radical polymerization of acrylic acid in liquid phase P in storage or process operation, content of acrylic acid which is at least 10 wt %, and which, in terms of weight contained in it of acrylic acid, additionally contains 100 ppm by weight to ≤ 5 wt% propionic acid and from 100 ppm by weight to ≤ 5 wt% of glyoxal. According to the invention to liquid phase p is added at least one chemical compound of copper element, and at least one chemical compound containing copper in one of degrees of oxidation +2, +1, added in amount which provides content of added copper in liquid phase P in terms of the molar amount of acrylic acid contained therein, in the amount of 0.01 mole ppm to 5 mole per cent, the liquid phase P is subjected to thermal separation different from crystallization.
EFFECT: effective prevention of undesirable radical polymerization of acrylic acid.
16 cl, 2 ex
