| 摘要 |
<p>PURPOSE:To advantageously obtain the subject compound by cooling a reacted solution to a specific temperature before conversion of raw material becomes to a specific value and increasing concentration of the aimed compound with crystallizing a part of the raw material in subjecting pentaerythritol to condensation reaction in a liquid phase with using an acid catalyst. CONSTITUTION:Pentaerythritol(PE) is subjected to condensation reaction in the presence of an acid catalyst at 200-260 deg.C temperature to synthesize dipentaerythritol(D-PE). In said process, a temperature of reacting solution is lowered below 195 deg.C, preferably to about 170-190 deg.C before conversion of PE becomes to >=25% to suppress by production of polypentaerythritol having higher molecular weight and simultaneously a part of PE is crystallized, then a reacted solution having increased concentration of D-PE is taken out by solid liquid separation to efficiently, industrially and extremely advantageously afford mainly D-PE formerly produced only as a by-product.</p> |
