偏苯三酸酐生产技术及现状分析

Trimellitic Anhydride Production Technology and Current Situation Analysis

偏三甲苯液相空气氧化法近年来经过不断技术改进,取得了较大进步,文章分析了该工艺制偏苯三酸酐的生产技术及现状,并对国内偏酐产业发展提出了具体建议:在建设新装置时,氧化反应可采用多级分层进料、单釜连续氧化工艺;产品精制可采用翅片式的熔融结晶器,以熔融结晶、升华粘附和溶剂洗涤相结合来降低偏苯三酸酐中杂质含量;溶剂和催化剂的回收、余热利用等可利用精馏塔冷凝器出口的高温油将脱水塔内的物料加热。

The liquid phase air oxidation method of trimethylbenzene has undergone continuous technical improvement in recent years and has made great progress.The article analyzes the production technology and current situation of trimellitic anhydride produced by this technology,and puts forward specific suggestions for the development of domestic partial anhydride industry,including adoption of multi-stage stratified feeding and single-pot continuous oxidation process in new plants,using of a fin-type melting crystallizer which combines melting crystallization,sublimation adhesion and solvent washing to reduce impurities in trimellitic anhydride,and using of the high temperature oil at the outlet of the rectification tower condenser to heat the materials in the dehydration tower for solvent and catalyst recovery,and waste heat utilization.