Study On The Separation Technology Of Man Made Musk DDHI

A new technology called distillation-fall film melt crystallization hybrid processwas developed to separate high boiling point and high melt point system such asMusk DDHI.At first, the solid-liquid equilibrium data of DDHI-DIPP system were determinedby a self-made device. The experimental data were correlated satisfactorily with threethermodynamic models: Wilson, NRTL and UNIQUAC activity coefficient equations.The parameters of three models for the binary system are related by the simplexmethod. The calculated values were in good agreement with the experimental data.Static melt crystallization and falling film melt crystallization were used to purifymixture of musk DDHI. The static melt crystallization could improve the massfraction of the musk DDHI from 95% to 99.5%. But the purity effect was not goodfor the lower purity system. So the static melt crystallization process was not suitablefor the distillation-melt crystallization hybrid process.Falling film melt crystallization was used to purify mixture of musk DDHI. It wasshown that the crystallization time, crystallization temperature, the superheat of stuff,sweating temperature and heating rate would influence the result of crystallization,after crystallization, purity of product was over 99%, and the yield was over 69%.And the falling film melt crystallization process was suitable for the distillation-meltcrystallization hybrid process.Experimental study on distillation-crystallization hybrid separation processescarried out by using mixture of DDHI as raw material. The purity of musk DDHI wasover 99.5%, the total yield of DDHI could be reached to 55%.Experimental study on distillation-falling film crystallization hybrid separationprocesses carried out by using binary system of dichlorobenzene as raw material also.The total yield of p-dichlorobenzene could be reached to 58%, and the purity ofp-dichlorobenzene was over 99.7%.The distillation-falling film melt crystallization hybrid process has a highindustry value for high boiling point and high melt point material.