Phase Equilibria Experiment And Model Study Of Phenolic And Ketone Related System From Biomass Pyrolysis Oil

Biomass,as a renewable energy source,has the advantages of being environmentally friendly and rich in raw materials.With the increasingly serious energy consumption and environmental pollution,the technology for converting biomass into energy and chemicals to replace fossil fuels has been attached much attention.Biomass pyrolysis technology is one of the most widely used processes in the production of bio-oil.Biomass pyrolysis oil is produced under the condition of high temperature without oxygen by pyrolysis technology.The analysis results showed that there were various phenols,ketones,aldehydes and other organic compounds in biomass pyrolysis oil.Some of these compounds are important organic chemical synthetic raw materials.These organic chemicals can be separated from biomass pyrolysis oil and used for chemical synthesis to replace fossil fuels and chemicals.It is not only beneficial to solve the environmental pollution caused by fossil fuels,but also conducive to the recovery and utilization of biomass resources.The study of phase equilibrium is the key and foundation of chemical separation.The relevant process design and device improvement need accurate and reliable phase equilibrium data.The study on phase equilibrium of biomass pyrolysis oil related systems(phenols and ketones)provides theoretical basis and technical guidance for industrial separation of biomass pyrolysis oil related systems.In this study,the vapor-liquid equilibrium data of phenolic compounds related systems(cyclohexane+4-methylguaiacol/4-ethylphenol/3,5-dimethylphenol/m-cresol)and ketones related systems(2-butanone+cyclopentanone,2,3-butanedione+cyclopentanone)of biomass pyrolysis oil were measured by Rose vapor-liquid equilibrium kettle under atmospheric pressure.The area test method and point test method were used to check the thermodynamic consistency.The activity coefficient model(NRTL,Wilson and UNIQUAC)is used for the regression calculation of binary vapor-liquid equilibrium experimental data,the corresponding binary interaction parameters are obtained,and the experimental data and the regression data are compared,and the results show that the agreement is consistent.The modified UNIFAC-Dortmund model was used to estimate the phenolic and ketone systems based on group contribution method in this work.For the phenolic system,the interaction parameters of C-CH₂functional group were regressed and used for the estimation and verification of other phenolic systems.For the ketone system,a new functional group CH₂COCH₂is defined,and the regression of the interaction parameters of the related functional groups is carried out.The new group interaction parameters were used to estimate ketone systems,and a good estimation result is obtained.In addition,the separation process of ketone mixtures was designed by the rigorous module Rad Frac of Aspen Plus based on the vapor liquid equilibrium data of the ketone system.The design goal is 99.7wt%product purity.The simulation results show that the purity of ketone products(2-butanone,2,3-butanedione and cyclopentanone)all reach the design goal.The process design can provide a technical basis for the industrial separation of ketones in biomass pyrolysis oil.