Method for separating dimethyl benzene and butyl acetate from industrial waste solvent

Abstract

The invention provides a method for separating dimethyl benzene and butyl acetate from industrial waste solvent. The method comprises the following steps of: a, performing atmospheric simple distillation to the industrial waste solvent to obtain colorless and transparent waste solvent to be separated; b, mixing the waste solvent to be separated processed through simple atmospheric distillation with water in weight ratio of 1 to 3:1 to obtain a heterogeneous azeotropic system, and then performing rectification separation operation to the heterogeneous azeotropic system in a batch rectificationtower; and c, performing continuous reflux for 30 to 100 minutes after performing infinite reflux for 30 to 60 minutes in the batch rectification tower, and sequentially distilling off butyl acetate and dimethyl benzene from the top of the tower. The method for separating dimethyl benzene and butyl acetate from industrial waste solvent has the advantages that the separation effect is good, the heating temperature of the method is 50 to 80 DEG C lower than that of conventional homogeneous batch rectification, the yield coefficient of the butyl acetate is 80 to 99 percent, the yield coefficientof the dimethyl benzene is 84 to 87 percent, the separated dimethyl benzene and butyl acetate can be reused, the entrainer can be recycled, no pollution is produced during the separation process, theenergy consumption is low, and the processing cost is low.

Description

technical field [0001] The invention provides a method for separating industrial waste solvents, in particular a method for separating xylene and butyl acetate from industrial waste solvents. Background technique [0002] A large amount of industrial waste solvents are produced in the production process of automobiles and parts, pesticide intermediates, paints, electronic equipment, petrochemical industries, etc. These waste solvents contain xylene, butyl acetate, alkyd, amino, acrylic and other paints, which are easy to Volatile, flammable, explosive, and highly toxic, it is listed as a first-class hazardous industrial waste, which is extremely harmful to the environment and human health. However, the solvent components in waste solvents have high economic value. With the shortage of oil supply and the continuous increase of paint production and varieties, the demand for p-xylene in various countries in the world is on the rise year by year, and its price has risen from 4,...

AI Technical Summary

Problems solved by technology

The incineration method not only wastes a large amount of organic solvents with important economic value, but also produces a large amount of toxic waste gas during the combustion process, causing secondary pollution to the atmospheric environment; the dilution method wastes a large amount of water resources and is likely to cause serious water pollution. Shortage is not desirable today

The vacuum distillation recovery requires high equipment, high energy consumption, and high recovery cost; the solvent recovery machine has the disadvantages of high energy consumption, low processing capacity, low separation efficiency, and low purity of the recovered solvent, especially for multi-component complex mixtures. The degree of separation is poor, and high-quality industrial-grade solvents cannot be obtained