| 摘要 |
PURPOSE:To make it possible to reuse a formaldehyde component and a phenolic component present in a concentrated solution formed in a concentration step in the production of a phenolic resin easily without providing any complicated step, by fractionating and recovering the solution according to the temperatures in the reaction kettle. CONSTITUTION:A concentrated solution formed in a step of producing a phenolic resin is recovered by the following process for reuse. A concentrated solution on the low-temperature side of the reaction kettle and one on the high- temperature side are separated from each other and recovered. The low- temperature side concentrated solution is cooled, and separated precipitates are recycled as a source of formaldehyde, and the high-temperature side solution is recycled as a source of phenol.
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