Study On The Hydroolysis Reaction And Separation Process Of Diketene Resdiue

Diketene is an extremely important chemical intermediate in the fine chemical industry,and diketene residue will be produced in its production process.The treatment method of residue is generally landfill or incineration,which not only wastes diketene and acetic anhydride in the residue of diketene,but also is not conducive to environmental protection.The reasonable disposal of diketene residue plays an important role in reducing environmental pollution,recycling resources and realizing economic value.This paper is based on the diketene residue treatment technology of Shandong Xinhua Pharmaceutical(Shouguang)Co.,Ltd.and mainly uses the raw materials provided by it to process the diketene residue by hydrolysis.By optimizing the operation parameters of the existing hydrolysate preparation and improving the product separation process,a continuous hydrolysis process of diketene residue is designed to recover acetone and acetic acid.The final purpose of making the acetone content not less than 90%,acetic acid content not less than 60% and acetone content in acetic acid not more than 3%.The main research contents are as follows:(1)A small-scale experimental device was set up,in which acetic acid was used as diluent to treat the residue of diketene by hydrolysis method.The effects of different operation parameters on hydrolysis reaction were studied in detail.The influence rules of oil bath temperature,diketene residue dropping time,holding time and acetic acid concentration on hydrolysis reaction were obtained,and the operation parameters in actual production were optimized.The components and contents of the hydrolysate were determined through small distillation of the hydrolysate and chromatographic detection of the hydrolysate and the distillate,which provided the basis for the subsequent distillation simulation calculation and process design of the hydrolysate.(2)The simulation processes of common side line distillation,azeotropic distillation and extractive distillation were established,and the effects of theoretical plate number,feed position,reflux ratio,azeotropic dosage and extractive dosage on the distillation effect were analyzed.According to the actual production conditions and production requirements,ordinary side line distillation was preferred to separate the hydrolysate,and a gas phase side line extraction process using acetic acid product at the bottom of the column was adopted to ensure the quality of the bottom product.(3)The industrial process of continuous hydrolysis of diketene residue was designed and a test platform was built.The experimental results met the actual production requirements.The continuous operation replaced the intermittent operation of the original process,which increased the level of automation and reduces labor intensity.