公开(公告)号：US5874659A

公开(公告)日：1999-02-23

申请号：US78380

申请日：1998-05-13

申请人： Christophe-Henri Pierre Lusson

发明人： Christophe-Henri Pierre Lusson

IPC分类号： C07C17/392 ,  C07C25/02 ,  C07C22/00

CPC分类号： C07C25/02 ,  C07C17/392

摘要： A crude bromotoluene mixture comprising at least 70 wt % of a mixture of p-bromotoluene and o-bromotoluene, and wherein the weight ratio of p-bromotoluene:o-bromotoluene is in the range of 50:50 to 99:1 is cooled to a temperature at which crystals of product enriched in p-bromotoluene are formed in a first residual mother liquor. After removing the residual mother liquor from the crystals of product enriched in p-bromotoluene, the crystals are partially melted to form a mixture of residual higher purity p-bromotoluene in the form of crystals, and a second mother liquor having a higher content of o-bromotoluene than said first residual mother liquor. This higher purity p-bromotoluene and the second mother liquor are separated from each other. The entire procedure starting with the above cooling step can be repeated as a second stage and again as a third stage each time using as the initial feed the residual higher purity p-bromotoluene that is separated from the second mother liquor of the preceding stage. Product of 99.5 wt % purity can be formed in this manner.

摘要翻译： 包含至少70重量％的对溴甲苯和邻溴甲苯的混合物的粗溴甲苯混合物，其中对 - 溴甲苯：邻 - 溴甲苯的重量比在50:50至99:1的范围内被冷却至 在第一残留母液中形成富含对溴甲苯的产物的晶体的温度。 在从富含对甲苯磺酸的产物的晶体中除去残余的母液后，晶体部分地熔化，形成晶体形式的残留较高纯度的对溴甲苯的混合物，并且含有较高含量的第二母液 - 溴甲苯比所述第一残余母液。 这种较高纯度的对溴甲苯和第二母液彼此分离。 从上述冷却步骤开始的整个过程可以作为第二阶段重复，并且再次作为第三阶段，每次作为初始进料使用与前一阶段的第二母液分离的残留的较高纯度的对溴甲苯。 可以以这种方式形成99.5重量％的纯度的产物。