Oxo synthesis catalyst and its preparation process and application in preparing acetic acid and acetic anhydride

Abstract

The present invention relates to positive and negative ion type bimetal catalyst with pyridine carboxylic acid as ligand and used for oxo synthesis of acetic acid and acetic anhydride. Of the catalyst, the active positive ion center is square planar cis-bicarbonyl structure formed with pyridine carboxylic acid and Rh(I); and the negative ion active component is coordination compound structure formed with pyridine carboxylic acid and RE metal La, Ce or Nd. Owing to synergetic effect of the special coordination compound structure and metals, the catalyst exhibits excellent activity in catalyzing methanol carbonylation to synthesize acetic acid and catalyzing methyl acetate carbonylation to synthesize acetic anhydride. The space time yield of acetic acid may reach 40 mol/L.hr, and that of acetic anhydride may reach 10 mol/L.hr. 本发明涉及一类以吡啶羧酸为配体的用于羰基合成乙酸、乙酐的正负离子型双金属催化剂。该催化剂正离子活性中心为吡啶羧酸与Rh(I)形成的螯合型正方平面顺二羰基配位结构，负离子活性物种为吡啶羧酸与稀土金属La、Ce、Nd的配位结构。由于配合物的特殊结构与金属间的协同作用，该催化剂在催化甲醇羰基合成乙酸、乙酸甲酯羰基合成乙酐的反应中，表现出优良的活性。其中，乙酸的时空收率最高达40mol/L·h以上，乙酐时空收率最高大于10mol/L·h。