FIELD: chemistry.
SUBSTANCE: invention relates to a method for continuous dissolution of a solid, in particular a slightly soluble solid, in a reaction medium. The method for continuous dissolution of a solid in a reaction medium includes the steps: a) providing a liquid by extracting part of the reaction medium from the first reaction vessel, wherein the reaction medium contains at least one unsaturated carboxylic acid anhydride of the general formula R-C(O)-O-C(O)-R, in which R is an unsaturated organic radical containing from 2 to 12 carbon atoms, at least one unsaturated carboxylic acid of the general formula R-COOH, in which R is defined above, at least one anhydride of aliphatic carboxylic acid and at least one corresponding aliphatic carboxylic acid, where R is not necessarily replaced by any required number of halogen atoms or CN groups; b) bringing the liquid obtained in step a) into contact with the solid in the second reaction vessel to form a solid solution, where the solid in the second reaction vessel is present as a fixed layer through which the liquid passes; and c) recirculation of the solution formed at stage b) into the first reaction vessel, while part of the reaction medium extracted at stage a) consists of aliphatic carboxylic acids in an amount of at least 90 wt. %, the temperature of the fixed layer is set in the range from 10°C to 80°C and the concentration of the solid in the solution obtained at stage b) is measured continuously using a spectrometer in the UV/visible region.
EFFECT: invention provides an improved method for continuous dissolution of a solid in a reaction medium, which eliminates the use of additional solvents.
13 cl, 1 tbl, 4 dwg
