离子交换法提取丙酸及联产丁二酸的工艺研究

发布时间：2018-04-26 03:36

  本文选题：费氏丙酸杆菌 + 丙酸　； 参考：《河北大学》2017年硕士论文

【摘要】：微生物发酵法生产丙酸受到越来越多的关注,但是人们的焦点主要聚集在如何解除产物反馈抑制、提高底物转化率等方面,对发酵液中丙酸的分离提取却鲜有关注。本论文研究和考察了ZGD630阴离子交换树脂吸附-解吸费氏丙酸杆菌发酵液中丙酸和丁二酸的工艺参数,建立了“两段式”层析法联产发酵液中丙酸和丁二酸的提取工艺,并完成了10L层析柱的放大试验,为丙酸和丁二酸的半连续耦合发酵奠定了基础。本论文主要取得了如下研究成果:(1)研究和考察了ZGD630阴离子交换树脂吸附分离费氏丙酸杆菌发酵液中丙酸等代谢产物的最佳吸附条件。结果表明,采用001×7阳离子交换树脂对发酵上清液进行酸化处理后,pH可降至1.5。此时,ZGD630阴离子交换树脂对丙酸和丁二酸的静态吸附载量分别为89.4 mg/g和108.2 mg/g,较初始发酵液(pH 6.8)的吸附载量分别提高了101.35%和71.74%。(2)考察了ZGD630阴离子交换树脂对酸化发酵液中丙酸和丁二酸的动态吸附特性。结果表明,酸化后的发酵液过量上样至装填有ZGD630阴离子交换树脂的层析柱时,丁二酸会优先被ZGD630阴离子交换树脂吸附,当发酵液中丁二酸被完全吸附后,丙酸才开始被吸附。此时,穿柱液按体积可分为三部分:0-2 BV,不含丁二酸、丙酸;2-6.5BV,不含丁二酸,含丙酸;6.5 BV,含丁二酸、丙酸三个部分(BV均指树脂体积)。(3)研究建立了“两段式”层析法联产丙酸和丁二酸的工艺,并确定了其操作参数。结果表明,首先采用层析柱Ⅰ吸附发酵液中的丁二酸,最佳的上样流速为3 BV/h,上样体积为10 BV,丁二酸可完全穿柱;然后将层析柱Ⅰ的穿柱液(不含丁二酸的部分)上样至层析柱Ⅱ,上样流速为3 BV/h,上样体积为5 BV,以确保其吸附饱和。(4)层析柱Ⅰ采用NaOH溶液进行洗脱,最适的NaOH溶液洗脱浓度为3 mol/L,洗脱流速0.45 BV/h,丁二酸最高浓度可达91.28 g/L,是发酵液中丁二酸浓度的7.1倍。层析柱Ⅱ采用H2SO4溶液进行洗脱,结果表明,最适的H2SO4溶液洗脱浓度为4 mol/L,洗脱流速0.6 BV/h,丙酸最高浓度可达97.02 g/L,是发酵液中丙酸浓度的4.4倍。(5)对上述工艺进行10 L层析柱的中试放大试验,取得了良好的效果。丙酸和丁二酸的回收率分别达到了88.12%和91.05%。
[Abstract]:More and more attention has been paid to the production of propionic acid by microbial fermentation, but the focus is mainly on how to remove the product feedback inhibition and improve the substrate conversion, but little attention has been paid to the separation and extraction of propionic acid from fermentation broth. In this paper, the process parameters of ZGD630 anion exchange resin for adsorption and desorption of propionic acid and succinic acid in the fermentation broth of Propionibacterium fermentum were studied, and the extraction process of propionic acid and succinic acid in the fermentation broth by "two-stage" chromatography was established. The amplification experiment of 10 L chromatographic column was completed, which laid a foundation for semi-continuous coupling fermentation of propionic acid and succinic acid. In this paper, the following research results were obtained: 1) the optimal adsorption conditions for the adsorption and separation of propionic acid and other metabolites from the fermentation broth of Propionibacterium fermentum by ZGD630 anion exchange resin were investigated. The results showed that the pH of ferment supernatant could be reduced to 1.5 after acidizing with 001 脳 7 cation exchange resin. The static adsorption capacity for propionic acid and succinic acid by ZGD630 anion exchange resin was 89.4 mg/g and 108.2 mg / g respectively, which was 101.35% and 71.74% higher than that of initial fermentation broth (pH 6.8). The effect of ZGD630 anion exchange resin on acidizing fermentation broth was investigated. Dynamic adsorption characteristics of propionic acid and succinic acid. The results showed that when the acidified fermentation broth was overloaded with ZGD630 anion exchange resin, the succinic acid would be preferentially adsorbed by ZGD630 anion exchange resin, and when the succinic acid in the fermentation broth was completely adsorbed, propionic acid would begin to be adsorbed. At this time, the liquid can be divided into three parts according to volume: 0-2 BV, no succinic acid, 2. 5 BV propionate, no succinic acid, 6. 5 BV propionic acid, and 5. 5 BV succinic acid. BV of three parts of propionic acid refers to the volume of resin. The process of producing propionic acid and succinic acid by "two-stage" chromatography has been studied and its operating parameters have been determined. The results showed that the best flow rate was 3 BV / h and the volume of the sample was 10 BV, and succinic acid could penetrate the column completely. Then the column I was eluted with NaOH solution at a flow rate of 3 BV / h and a volume of 5 BV in order to ensure its adsorption saturation. The optimal elution concentration of NaOH solution is 3 mol / L, the elution rate is 0.45 BV / h, and the highest concentration of succinic acid can reach 91.28 g / L, which is 7.1 times the concentration of succinic acid in fermentation broth. Chromatographic column 鈪，

本文编号：1804350