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Sugar cane, sugar cane juice clarification process is the key to high-quality sugar products, currently in production is Sulfitation carbonate method, these methods are not only complex process, high investment in equipment and pollution serious product quality is unstable. Some new techniques such as ion exchange resins, etc., and because the technology, cost, and other issues, it is difficult to promote. Therefore, this project will clarify activated carbon introduced sugar main research contents include: activated carbon to clarify the process conditions of the sugar by orthogonal amount of activated carbon adsorption temperature, adsorption time, pH for sugar decolorization rate, Jane purity, turbidity, the degree of influence of the settling time and the size of the order, to get the optimal conditions for the amount of 5 g of activated carbon adsorption temperature of 60 ° C, adsorption time 30 min, pH value of 7.0. Under this condition, the decolorization rate reached 46.1%, 86.4% purity, the haze 43 IU, the settling time of 1.34min; compare with phosphate - the sulfite method, the results showed that the decolorization rate significantly improve the settling time activated carbon adsorption to clarify shortened purity to improve the effect of turbidity is less than the phosphate - Sulfitation, sucrose recovery and phosphoric acid - quite Sulfitation; also carried out kinetic studies, including adsorption rate and adsorption isotherms Research results show that the active carbon used sugar reaction the film diffusion master steps, and active carbon used sugar faster, can be used as an excellent sugar clarifying agent. 2 further studies by microwave modified so that the activated carbon to clarify the effect of the sugar to a better level. Response surface methodology to optimize microwave modified activated carbon three conditions to obtain optimal combination of microwave power 640 W, irradiation time of 5.0 min, the amount of activated carbon loading of 9.86 g. Characterization of activated carbon before and after the modification and analysis XRD spectra showed that microwave treatment, activated carbon crystallite structure changes, crystallite interlayer spacing smaller, to improve the degree of graphitization, and this is detrimental to the adsorption; the SEM figure shows, by microwave treatment activated carbon pore walls thinner, the aperture more transparent, more developed pore of activated carbon, which not only clarify role in promoting sugar, but also improve the adsorption rate. At the same time, the microwave for the change of the carbon surface chemical groups, the carbon surface basic functional group increased, to reduce the acidic functional group, which facilitate its adsorption of the non-sugar sugar. Therefore infer that microwave radiation on the activated carbon surface structure and surface chemistry group change is a major factor in the microwave modified activated carbon performance. By response surface methodology Microwave regeneration of activated carbon process to obtain the optimum conditions: microwave power 600W, irradiation time of 4.4 min, activated carbon load of 11.00 g. Further studies repeated regeneration of activated carbon, and SEM analysis showed that the activated carbon regenerated after 6 times, still a large number of pores leading to the decrease of the internal adsorption performance is not more than 10%, and can be repeatedly recycled.
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