公开(公告)号：US4650912A

公开(公告)日：1987-03-17

申请号：US716061

申请日：1985-03-26

申请人： Michael C. Pohl ,  Richard V. C. Carr ,  John E. Sawicki

发明人： Michael C. Pohl ,  Richard V. C. Carr ,  John E. Sawicki

IPC分类号： C07C201/16 ,  C07C79/10

CPC分类号： C07C201/16

摘要： In a method for denitrifying the nitric acid- and nitrous acid-containing spent acid phase from the nitration of an aromatic hydrocarbon by the mixed acid process which comprises forming a denitrification reaction medium by contacting the spent acid phase with an aromatic hydrocarbon under nitration reaction conditions to recover the nitric acid by the formation of a nitroaromatic hydrocarbon, the improvement which comprises(a) adding an amount of aromatic hydrocarbon which is slightly less than or equal to the stoichiometric amount necessary to deplete the spent acid phase of nitric acid,(b) photometrically monitoring the denitrification reaction medium for the appearance of a dark red to black color, and(c) upon detection of such color, adjusting the aromatic hydrocarbon:nitric acid molar ratio in the denitrification reaction medium to eliminate the color by reducing the aromatic hydrocarbon feed rate, or adding nitric acid to the denitrification reaction medium.

摘要翻译： 在通过混合酸法使芳族烃硝化反硝化含硝酸和亚硝酸的废酸相的方法中，其包括通过在硝化反应条件下使废酸相与芳族烃接触来形成反硝化反应介质 通过形成硝基芳族烃来回收硝酸，其改进包括（a）加入一定量的少于或等于耗尽硝酸废酸所需化学计量的芳烃，（b ）用于对脱氮反应介质进行光度监测，以显示深红色至黑色，以及（c）在检测到这种颜色后，调节反硝化反应介质中的芳烃：硝酸摩尔比以通过还原芳族化合物来消除颜色 烃进料速率，或向脱氮反应介质中加入硝酸。