| abstract |
The invention concerns the working up of reaction mixtures containing undesirable high-boiling by products, low-boiling educts and the product sought, the boiling point of the product sought lying between the boiling points of the high- and low-boiling compounds. On completion of the reaction, the reaction mixture is distilled in a first column (3) placed on the reaction vessel (1). In this column, a mixture of the low-boiling compounds and the product sought is continuously separated out of the reaction mixture. The high-boiling compounds remain in the reaction vessel (1). That part of the mixture which distils over is redistilled in a second column (8) which is physically separate from the reaction vessel (1) and the first column (3). This economic method produces a high-purity product, makes washing of the raw product, with the resulting problems associated with disposal of the washings, unnecessary and reduces the working-up time. |