| Dihydroxyacetone is an important fine chemicals,has good biological activity,which has a wide range of applications in functional food,cosmetics and chemical and other fields,so the development of dihydroxyacetone refining technology and application research has a very important value and broad market prospects.At present,dihydroxyacetone production is mostly produced by microbial fermentation,microbial fermentation production of dihydroxyacetone has its advantages,such as high yield,friendly to the environment,but the fermentation medium contains large amounts of water and other impurities,resulting in the refining process of dihydroxyacetone extraction is difficult and needs high energy consumption,detrimental to their wide range of applications.In dihydroxyacetone extraction process,fermentation liquid of impurities impact on the crystallization process significantly,trials with activated carbon on dihydroxyacetone fermentation liquid to decolorize,every solution of 100 ml adding 5g powder activated carbon DS-305,decolorization rate was 95.88%,dihydroxyacetone retention rate was 94.41%.Ethanol or acetone and concentrated liquid volume ratio was 3:1,protein,nucleic acid,salt and other impurities of concentrate removal has better effect;the experiment selected the ethanol as the alcohol solution,ethanol precipitation,protein and salt removal rates were 97.40%and 98.06%,and alcohol precipitation process of dihydroxyacetone the retention rate of 94.78%,the impurity removing effect was remarkable.Solubility of dihydroxyacetone dissolute in water and in different concentration of ethanol showed dihydroxyacetone fitting in the ethanol content of more than 90%ethanol solution to crystallize,at 5? ethanol crystallization after 30 h,dihydroxyacetone yield was 87.25%,and the purity was 98.65%.This paper has successfully for the first time using vacuum membrane distillation technique in dihydroxyacetone refining process,the vacuum membrane distillation dihydroxyacetone fermentation liquid and the feasibility of operating parameters is studied.Elevating temperature,vacuum and feed rate are helpful to enhance vacuum distillation process of water flux,with the feed concentration,membrane flux declines.After membrane distillation 10 h,fermentation liquid is concentrated to the original 3.62 times,dihydroxyacetone retention rate is above 92%.We construct the vacuum membrane distillation process of dihydroxyacetone fermentation liquid mathematical model,the experience shows that the mathematical model has a good consistency;it provides a new choice to the water removal process in the refining dihydroxyacetone of enrichment technology.Dihydroxyacetone fermentation liquid contains large amounts of water,so in the development of dihydroxyacetone feed additives in the process to select appropriate granulation technology.The paper used spray drying technology,with maltodextrin,?-cyclodextrin,Arabia rubber compounding,when maltodextrin was 60%,?-cyclodextrin was 8%,Arabia rubber was 4%(all to the fermentation broth in solids ratio),the quality and color of the production were good dihydroxyacetone,Under this condition,the powder rate of dihydroxyacetone feed additive is 86.42%,the retention rate of dihydroxyacetone is 87.14%,and the feed additives contains 51.32%dihydroxyacetone,40.11%ingredients,6.26%water and 2.31%other compositions.The paper investigated the influence of spray drying technology of dihydroxyacetone feed additive process of the operating parameters,when the inlet air temperature was 140°C,the feed speed was 7.50 mL/min,compressed air flow rate was 35 m3/h,feed temperature was 30-35?,that could achieve better drying effect and better quality,color of dihydroxyacetone feed additive. |
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