以粉末状活性炭为脱色剂对L-乳酸进行脱色,在单因素的基础上,采用三元二次回归正交旋转组合设计,建立了脱色工艺参数与脱色总效率的数学回归模型,利用Maltab软件绘制出响应曲面,分析了脱色工艺参数对脱色总效率的影响。用Matlabfmincon函数求解模型,得到最优脱色条件为:活性炭添加量为0.318%,脱色温度为43.18℃,脱色时间为18.83min。通过频数分析得到具有95%概率保证的脱色总效率大于70%的参数范围,即活性炭添加量为0.395%-0.695%,脱色温度为56.88-69.84℃、脱色时间为15.68-22.58min,为L-乳酸发酵液活性炭脱色工艺参数的选择提供理论依据。

The powdered activated carbon was used as discoloring agent for decolorization in the separation of L-lactic acid.The mathematical regression models between the total discoloration efficiency rate and its influencing factors were attained by the combination design of quadratic orthogonal rotation based on the results of the single-factor design.The software Matlab was used to draw response surface and analyze the effects of technology parameters on the total efficiency rate of discoloraization.The optimum process parameters were:activated carbon 0.318 %,discoloring temperature 43.18 ℃ and discoloring time 18.83 min.Frequency analytical method showed that optimum conditions for 95 % probability of obtaining 70 % discolorization were:activated carbon 0.395-0.695 %,discoloring temperature 56.88-69.84 ℃,and discoloring time 15.68-22.58 min.The study provided a foundational consult to choose operating parameters for decolorization in the separation of L-lactic acid.