丙烯醛制备1,3-丙二醇的中型试验研究

对丙烯醛水合、加氢制1，3-丙二醇工艺进行了中试研究，主要对小试技术的可靠性进行验证。结果表明，丙烯醛经水合、加氢制1，3-丙二醇的工艺技术可行，反应器、精馏塔等设备设计合理。中试丙烯醛水合单程转化率为45％～55％，3-羟基丙醛选择性达到了93％左右，3-羟基丙醛加氢收率接近100％，产品1，3-丙二醇的醛基质量分数降至5μg／g以下。与小试结果相比较，中试的水合选择性明显提高，加氢催化剂活性寿命延长。     

以葡萄糖为辅助底物发酵生产1,3-丙二醇的研究

采用Klebsiellapneumoniae对葡萄糖作为辅助底物发酵生产 1 ,3 丙二醇进行了研究。结果表明葡萄糖单独作为底物发酵时不生成 1 ,3 丙二醇。以葡萄糖和甘油为混合底物时 ,则可以显著提高菌体浓度 ,但是 1 ,3 丙二醇浓度和甘油到 1 ,3 丙二醇转化率没有提高。在甘油为底物的批式发酵过程中 ,通过流加葡萄糖作为辅助底物可以提高甘油到 1 ,3 丙二醇的摩尔转化率 ,同时可缩短发酵时间。通过选择合适的葡萄糖流加速率 ,较以甘油为单一底物的发酵结果 ,1 ,3 丙二醇的摩尔转化率最高可达0 649,提高了 53 4% ;生产强度为 1 0 0 5g/ (L·h) ,提高了 1 39 9%。     

PTT纤维的制备及应用

介绍了聚对苯二甲酸丙二酯（ＰＴＴ）纤维及其原料１，３－丙二醇、对苯二甲酸丙二酯的制备方法，综合评述了这种新型聚酯纤维的特性和用途。建议国内开展ＰＴＴ纤维的生产和研究。     

Zr(SO4)2/γ-Al2O3固体酸催化合成环己酮1,2-丙二醇缩酮

通过直接浸渍-焙烧等方法,制备了Zr(SO4)2/γ-Al2O3催化剂,以环己酮和1,2-丙二醇为原料合成了环己酮1,2-丙二醇缩酮。考察了催化剂的焙烧温度、催化剂的质量分数、原料摩尔比、带水剂体积、回流时间对反应的影响。最佳反应条件为:焙烧温度为550℃,Zr(SO4)2的质量分数为20.0%,催化剂的质量分数为5.0%,环己酮与1,2-丙二醇的摩尔比为1∶1.5,甲苯的体积为15 mL,回流时间为3 h。环己酮1,2-丙二醇缩酮的收率可达98.7%,纯度达到99.6%。     

Application of a two‐stage temperature control strategy to enhance 1,3‐propanediol productivity by Clostridium butyricum

BACKGROUND: The purpose of the present work was to enhance 1,3‐propanediol productivity during the batch cultivation on a type of raw glycerol by application of a two‐stage temperature control strategy. RESULTS: First, the effect of the raw glycerol on microbial growth and 1,3‐propanediol production was investigated. The highest 1,3‐propanediol productivity, 1.93 g L^?1 h^?1, was achieved when the initial raw glycerol concentration was 6% (v/v). Second, the effect of temperature on microbial growth and 1,3‐propanediol production was investigated and kinetic analysis was carried out. The results indicated that 37 °C favored microbial growth while 35 °C was best for 1,3‐propanediol production. Finally, a two‐stage temperature control strategy was applied in 1,3‐propanediol production. The incubation temperature was kept at 37 °C from inoculation to 2 h and then switched to 35 °C. Compared with batch cultivations at 35 and 37 °C, the fermentation time was shortened from 10 to 9.2 h, resulting in an increase in 1,3‐propanediol productivity of around 11%. CONCLUSION: 1,3‐propanediol productivity was enhanced effectively by application of a two‐stage temperature control strategy. © 2012 Society of Chemical Industry     

Unstructured kinetic model for reuterin and 1,3‐propanediol production by Lactobacillus reuteri from glycerol/glucose cofermentation

BACKGROUND: Lactobacillus reuteri is unable to grow on glycerol as sole carbon and energy source hence, glycerol is used as an alternative hydrogen acceptor during growth on available carbohydrates. Thus, glycerol is converted to reuterin and 1,3‐propanediol (1,3‐PDL), both products with interesting industrial applications. These compounds are commonly produced by using resting cells in two‐step fermentation processes. RESULTS: The glycerol/glucose cofermentation by L. reuteri yields reuterin and 1,3‐PDL at a glycerol concentration higher than 100 mmol L⁻¹. An increase of glycerol concentration from 200 to 400 mmol L⁻¹ showed no additional stimulatory effect on ethanol and acetate production but consistently reduced the lactate concentration. It was also found that reuterin concentration reached a maximum value and subsequently decreased due to its conversion to 1,3‐PDL. An unstructured kinetic model was proposed to describe simultaneously microbial growth, substrates consumption and products formation. A multi‐response nonlinear regression analysis based on Marquardt algorithm combined with a Runge‐Kutta integration method was used to obtain the values of the fitting parameters. CONCLUSIONS: The optimum concentration of glycerol for maximum reuterin and 1,3‐PDL production was 200 mmol L⁻¹. The complete process was satisfactorily described by the kinetic model proposed. Copyright © 2008 Society of Chemical Industry     

MCM-41分子筛负载磷钨钼酸催化合成环已酮1，2-丙二醇缩酮

以MCM-41分子筛负载磷钨钼杂多酸为催化剂，以环己酮和1，2-丙二醇为原料合成了环己酮1，2-丙二醇缩酮，探讨了MCM-41分子筛负载磷钨钼杂多酸催化剂对缩酮反应的催化活性，较系统地研究了原料量比、催化剂用量、反应时间诸因素对缩酮反应的影响。实验表明，MCM-41分子筛负载磷钨钼杂多酸催化剂是合成环己酮1，2-丙二醇缩酮的良好催化剂，在n（环己酮）：n（1，2-丙二醇）=1：1．6，催化剂用量为反应物总质量的0．20％，环己烷作带水剂，反应时间45min的优化条件下，环己酮1，2-丙二醇缩酮的收率可达89．1％。     

克雷伯杆菌生产1,3-丙二醇关键酶发酵条件研究

研究了克雷伯杆菌生产1,3-丙二醇关键酶(甘油脱氢酶、1,3-丙二醇氧化还原酶、甘油脱水酶)的发酵条件。研究各种碳源、无机氮源、有机氮源及无机盐对产酶的影响,应用均匀设计、神经网络和遗传算法优化发酵培养基组成,结果为(gL-1):甘油30、KCl 1.6、NH4Cl 6.7、CaCl2 0.28、酵母浸膏2.8。在温度37C、初始pH 7.0、摇床转速200rmin-1和接种量5%条件下,发酵24h,无细胞抽提液中甘油脱氢酶、1,3-丙二醇氧化还原酶和甘油脱水酶活力(U·mg-1)分别为9.16、18.72、0.48,发酵34h,发酵液中1,3-丙二醇(1,3-PD)最大浓度为7.96gL-1。代谢过程中关键酶酶活与1,3-PD峰值出现时间不一致,且提早于1,3-PD峰值的出现。此外,结果表明优化后的培养基去除了多种微量元素,克雷伯杆菌生产1,3-丙二醇关键酶可以在微氧条件下进行。