The Study On The Reaction-Distillation Process Of Sec-butyl Acetate Hydrolysis

Sec-butyl alcohol(SBA)is an essential chemical raw material,and high-purity SBA can be used to synthesize methyl ethyl ketone,herbicide,etc.However,more problem also exist in the conventional synthesize method of SBA,like:higher energy consumption,higher equipment investment.With the synthesis technology of sec-butyl acetate(SBAC)industrialized which creates more overcapacity,the solution of using SBAC as the material to synthesize SBA has attracted much attention.Among,the synthesize method of SBAC hydrolysis has some advantages than other synthesize method,such as less by-products,wider raw material sources.In recent years,some enterprises have tried to synthesize SBA with SBAC hydrolysis,but the degree of hydrolysis is limited.This topic will explore operating conditions for the continuous reaction distillation hydrolysis process,the continuous tubular hydrolysis process and the intermittent hydrolysis process for SBAC hydrolysis with the experimental research.Then,this topic try to establish the steady state model of the hydrolysis process which combined with pressure-swing distillation with using Aspen Plus software.In the end,the topic will verify the feasibility of industrialization and puts forward the optimal hydrolysis process combined with pressure-swing distillation.Specific research contents include:(1)In the present study,the kinetics experiments were conducted under different conditions,and the kinetic data which was obtained from experiments were correlated by Matlab,and the pseudo-homogeneous model was considered and verified.The result indicated that the hydrolysis of SBAC is an endothermic reaction,and the reaction heat is 14.4046kJ·mol-1.Then,the hydrolysis of SBAC will reach equilibrium after 32h under the conditions that the molar ratio of reactants with 2,the catalyst mass fraction with 3.0%(wt)and the reaction temperature with 354.15K.(2)In the continuous hydrolysis process experiments,the continuous reaction distillation column and continuous tubular reactor for the SBAC hydrolysis are compared under different reaction temperatures,molar ratios of reactant,and so on.The result indicated that the conversion hydrolysis of SBAC of the continuous reaction distillation column is 32%under the conditions that the operating pressure with 0.3MPa,the operating reflux ratio with 5 and the molar ratio of reactants with 7.The conversion hydrolysis of SBAC of the continuous tubular reactor is 38%under the conditions that the liquid hourly space velocity with 0.57m3·m-3·h-1,the reaction temperature with 373.15K and the molar ratio of reactants with 1.(3)The study based on the hydrolysis kinetics model and continuous hydrolysis process,the steady state model of continuous hydrolysis process and the steady state model of pressure-swing distillation process was established.According to the experimental results and model,a continuous hydrolysis process which combined with pressure-swing distillation and an intermittent hydrolysis process which combined with pressure-swing distillation was established.All three kinds of processes can obtain the SBA which purity greater than 0.9999.In the continuous reaction distillation hydrolysis process combined with pressure-swing distillation,the single pass conversion of SBAC is 30%,and the yield of SBA is 98%.In the continuous tubular hydrolysis process combined with pressure-swing distillation,the single pass conversion of SBAC is 33%,and the yield of SBA is 99%.In the intermittent hydrolysis process combined with pressure-swing distillation,the single pass conversion of SBAC is 72%and the yield of SBA is 99%under molar ratios of water to SBAC is 8.The cyclic conversion of SBAC was greater than 99%in three processes.Then,compare to the comprehensive benefits of three kinds of process.And the result showed that the process of intermittent hydrolysis combined with pressure-swing distillation was the more suitable process synthesizing high purity SBA with SBAC hydrolysis.