Process for the purification of toluene diisocyanate incorporating a dividing-wall distillation column for the final purification
    8.
    发明授权
    Process for the purification of toluene diisocyanate incorporating a dividing-wall distillation column for the final purification 有权
    用于纯化含有分隔壁蒸馏塔用于最终纯化的甲苯二异氰酸酯的方法

    公开(公告)号:US07108770B2

    公开(公告)日:2006-09-19

    申请号:US10687157

    申请日:2003-10-16

    摘要: Toluene diisocyanate is recovered from a crude distillation feed containing less than 2% by weight of phosgene by(a) fractionating the crude distillation feed containing less than 2% by weight of phosgene to remove the solvent and optionally the reaction residues to produce a crude toluene diisocyanate feed containing less than 20% by weight of solvent and(b) separating the crude toluene diisocyanate feed containing less than 20% by weight of solvent in a divided-wall distillation column into four product fractions P1–P4. P1 is a vapor phase low-boiler and solvent-enriched gas stream, P2 is a low-boiler and solvent-enriched product, P3 is a high boiler-enriched bottoms product containing toluene diisocyanate and P4 is a toluene diisocyanate product stream lean in low-boilers, high-boilers and reaction residues.

    摘要翻译: 通过(a)将含有少于2重量%的光气的粗蒸馏进料分馏以除去溶剂和任选的反应残余物以产生粗甲苯,从含有小于2重量%的光气的粗蒸馏进料中回收甲苯二异氰酸酯 含有少于20重量%溶剂的二异氰酸酯进料和(b)在分壁蒸馏塔中将含有少于20重量%溶剂的粗甲苯二异氰酸酯进料分离成四个产物馏分P1-P4。 P1是蒸气相低沸点和富溶剂的气流,P2是低沸点和溶剂富含的产物,P3是含有甲苯二异氰酸酯的高富含塔底物的塔底产物,P4是低浓度的甲苯二异氰酸酯产物流 锅炉,高锅炉和反应残渣。