Activated Carbon To Clarify The Sugar Modified Its Microwave And Regeneration

The clarification of cane juice is a key process in cane sugar mill. The popular processes are carbonic acid method and sulfurous acid method at present. These methods are complex, high investment, contaminative and wavy in quality of sugar products. Some new techniques, for example, ion exchange resin and cationic surfactant, are difficult to generalize for cost and other causes. Accordingly, in this case we clarify cane juice using active carbon. The follow is the main contents in this paper:1. The effects of active carbon dosage, disposing temperature, disposing time and pH value on the results of clarification were discussed by orthogonal test. The optimum conditions of the clarification for 150 mL cane juice were obtained as following:active carbon dosage 9g, disposing temperature 60℃, disposing time 30min and pH value 7.0, and under which the decolouring ratio is 46.1%, the purity of juice is 86.4%, the turbidity of purified juice is 43IU, the sedimentation time is 1.34min. Compared with phosphoric acid and sulfurous acid method, the decolouring ratio and sedimentation time were improved markedly, and the purity and the turbidity of juice were increased also.2. The effects of power of microwave, time of microwave and active carbon dosage on the capacity of active carbon were discussed by response surface. The optimum conditions of the modification were obtained as following:power of microwave is 640W, time of microwave is 5min, and active carbon dosage is 9.86g. And after analyzing the character of surface of active carbon, the XRD chart shows that microwave makes the distance of layers of active carbon become slimmer, which is adverse for clarification; and the SEM chart shows that microwave makes the holes of active carbon be more and more exquisite, which is advantaged not only for clarification but also for the velocity. And microwave augments alkalescence functional groups and decrease acidic functional groups of active carbon. The carboxyl and the phenolic hydroxyl groups were decomposed markedly, it is also advantaged. So, the variation of microcosmic structure and chemical structure of surface of active carbon are the main causes.3. The effects of power of microwave, time of microwave and active carbon dosage on the capacity of regeneration active carbon were discussed by response surface. The optimum conditions of the regeneration were obtained as following:power of microwave is 600W, time of microwave is 4.4min, and active carbon dosage is 11.Og. By researching the SEM charts, it shows the capacity of active carbon declines less than 10% after 6 times of regeneration.