Study On Optimization Of Clarification Processing Conditions Of L-ribose

L-ribose which is a kind of important pharmaceutical intermediates is a new type of monosaccharide in recent years. Its production methods include chemical synthesis, microbial transformation and differential phase isomerism, etc. This paper mainly studies the preparation of transfer L-arabinose to L-ribose using the technique of epimerization, including the dosage of catalyst, reaction temperature, reaction time and reaction of the pH value of the process and so on, separately carried on the single factor test, orthogonal test and the pilot test verification.After the single factor test and orthogonal test, the optimum process conditions of epimerization as follows:ammonium molybdate dosage is0.20%, isomerism temperature is120℃, L-arabinose concentration is20%, heterogeneous time is120minutes. Under this condition the purity of L-ribose of system is27%.The refining process of L-ribose includes L-arabinose crystallization, chromatographic separation, concentration, L-ribose crystallization. At the beginning, after epimerization, the purity of L-ribose in the system is only about27%, but L-arabinose is65%. Then through the crystallization method some L-arabinose was separated, and in the mother liquor L-ribose purity is increased to41%. The single column evaluation test of crystallization mother liquor was studied, it is confirmed that L-ribose and L-arabinose could be separated. After chromatographic separation, the purity of L-ribose is increased to more than95%. L-ribose section though concentration, discoloring treatment and the organic solvent crystallization, and get L-ribose products, its purity is more than99%, and crystallization yield is63%.The pilot test verification was done after underbrush, input L-arabinose600kg in total, and get L-ribose crystallization75.5kg, yield increased by5%than before.