2，3-丁二醇的发酵及盐析分离工艺

采用克雷伯氏菌（Klebsiella pneumoniae CICC 10011）发酵生产2，3-丁二醇，并对2，3-丁二醇的盐析分离工艺进行了考察。通过实验确定了以葡萄糖为底物微氧批式流加发酵的条件，发酵液中2，3-丁二醇和3-羟基丁酮的质量浓度分别为90．98g/L和12．40g/L，2，3-丁二醇的摩尔转化率为82．7％，生产强度达到2．1g/（L·h）。对发酵液中2，3-丁二醇的盐析分离研究表明，K2HPO4和K3PO4对2，3-丁二醇的盐析效果优于K2CO3。当发酵液浓缩70％后，加入质量分数为45％的K，HPO4，2，3-丁二醇的分配系数达到9．10，回收率为79．37％；上相中2，3-丁二醇的质量浓度达到420g／L；此时3-羟基丁酮的分配系数和回收率分别为11．9和83．48％。

Fermentation and salting-out Separation of 2,3-butanediol

The bioconversion of 2,3-butanediol by Klebsiella pneurnoniae CICC 10011 was studied with a medium based on glucose in fed-batch fermentations, and the salting out separation was explored. The final concentration of 2,3-butanediol and aeetoin in the fermentation broth reached 90. 98 g/L and 12. 40 g/L, respectively. The molar yield of butanediol was 82. 7% and the productivity was 2. 1 g/（L·h）. The effects of concentration cycles and salt concentrations on the extraction of 2,3-butanediol in flocculated broth were also studied. When the fermentation broth was concentrated to 70%, 45% K2HPO4 was added ,the parti- tion coefficients and the recovery rate of 2,3-butanediol and acetoin reached 9. 10, and 79.37%, respectively. The concentration of 2,3-butanediol in top phase reached 420 g/L,the partition coefficient and the recovery rate reached 11.9 and 83.48%. Results indicate that the process has advantages of simple, energy saving, and good potential for application.