Study On The Process Of Separation And Purification Of D-Ribose From The Fermentation Broth By Reactive Crystallizing

D-ribose, which is important for physiology, can be made into VB2 and nucleic acid medical. In recent years, with the development of D-ribose fermentation, the cost of separation was the most of the cost of total product. It's very important to D-ribose product that decrease the separated cost and increase the purify ratio of D-ribose. The process of separation and purification of D-ribose from the fermentation broth by reactive crystallizing has been very important aspect in research. On the base of the ferment system of microbe, this paper studied the process of separation and purification of D-ribose from the fermentation broth by reactive crystallizing.In this paper, firstly, removed proteins by polysulfone ultrafiltration membrane in the fermentation broth. Secondly, separated and purified of D-ribose from the fermentation broth by reactive crystallizing. Thirdly, removed the aniline from the crystal, which had been obtained by reactive crystallizing. And at last, concentrated the D-ribose solution, cooling, and then the D-ribose can be obtained by crystallization. The object matter as follows:1. All of the mensurate method had been used in this paper was summarized. The method of measurement of D-ribose concentration in the fermentation broth by spectrophotometry (the measured wavelength is 670nm), the method of measurement of proteins concentration by UV spectrophotometry, the method of measurement of pigment concentration in the fermentation broth by spectrophotometry (the measured wavelength is 340nm), and the method of measurement of aniline is use the reaction of NaClO and aniline, this reaction can be appeared purple.2. In this paper, removed proteins from the fermentation broth by polysulfone ultrafiltration membrane were studied; the effect of membrane surface characteristic on the degree of proteins deprivation was studied. The experiment indicated that the membrane permeance flux was direct proportion with pressure when the pressure was 0.02~0.04MPa. While the pressure was higher, it had not this character. It was a good operation that entraps the proteins of D-ribose fermentationbroth by using membrane separation. When the fermentation broth pH was 5.5-6.0 and ethanol volume 15% of fermentation broth volume, the protein entrapment ratio achieved 90%.3. The mechanism and operated condition of reactive crystallizing between D-ribose and aniline had been studied in this paper. When D-ribose concentration was 10g/100mL, aniline and D-ribose was 1:1, the fermentation broth pH was 7~8, and ethanol volume50% of fermentation broth volume, reactive temperature was 30℃, the crystallizing temperature 4℃,the most crystal can be obtained was 1.105g crystal/g D-ribose.4. The crystal character was studied, at 25℃ the solubility was 1.638g when the volume inverse proportion was 30:100(C2H5OH : H2O), the solution pH was 7.5. Removed aniline from the crystal and D-ribose crystallizing was studied, the crystal saturated liquor was heated by vapor at 60℃ and the vacuum<0.08MPa, after 16h, all the aniline can be removed, and D-ribose solution can be achieved. The solution was concentrated at 45℃,and the added alcohol, concentrated at 40℃,repeated several time. At last, the concentration was about 20g/100mL, in 4℃ environment for days then the crystalloid can be obtained. The product ratio was about 31.5%.