The Research Of Separation And Purification Technology Of 1,3-propanediol From Fermentation Broth

In the field of chemical industry,1,3-propanediol(1,3-PD)can be used as an raw material,and widely used in pharmaceuticals,textile printing and dyeing,coatings,inks,antifreeze,lubricants and other fields,nowadays,the focus of attention is the synthesis of polyethylene terephthalate(PTT),a new type of polyester material,which is 1,3-PD as monomer and benzene two formic acid responsing.1,3-PD production methods are microbial fermentation and chemical synthesis.In recent years,with the excessive exploitation of petrochemical resources caused by scarce,microbial fermentation production of 1,3-PD become a hot research.At present,the microbial fermentation production of 1,3-PD has reached a higher level of fermentation,but the composition of fermentation broth is very complex,and 1,3-PD and residual glycerol have strongly hydrophilic and high boiling,so downstream separation becomes more difficult.First,fermentation conditions and the coposition determination of fermentation broth were studied in 50 L fermentor by Klebsiella pneumonia?aldH.Secondly,the fermentation broth was pretreated by ultrafiltration method.The results showed that,numbered SMN-130 roll-ultrafiltration membrane of the molecular weight cutoff 250 Dal can be a good interception off all bacterial fermentation broth and protein removal rates were 97% and 93%,reducing the difficulty of the subsequent separation.Then,activated carbon and oxidation remove broth pigment and the residual glycerol,the residual glycerol of fermentation broth converted into salts,the fermentation broth's salts were removed by ion exchange method,1,3-PD was obtained by vacuum distillation,pigment removal rate was 98.3%,the conductivity decreased to 140??/cm.Fermentation broth through membrane filtration,activated carbon decolorization,oxidation of glycerol,ion exchange,vacuum distillation process steps,the yield of the final 1,3-PD is 90% and purity is higher than 98%.In this study,instead of the traditional method of high-temperature distillation,the combination of three technologies including chemical oxidation,distillation,and microfiltration were used in 1,3-PD refination?This research provides a new way to solve the high energy consumption during 1,3-PD refination from fermentation broth.