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稀酸水解菊芋制乙醇技术研究 总被引:1,自引:0,他引:1
考察了固液质量比、酸浓度、反应温度和反应时间4个条件对菊芋粉稀酸水解的总糖浓度和总糖转化率的影响。结果表明,菊芋稀酸水解的最优化条件为:固液比0.3,硫酸浓度3%,反应温度80℃,反应时间90 min。在此条件下水解菊芋,水解液中的总糖浓度为24.1%,总糖转化率为80.3%;水解液经过中和后,接入酵母菌发酵产乙醇,最终乙醇浓度可达到10.4%,乙醇得率为86.4%。 相似文献
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《应用化工》2022,(10)
对微晶纤维素在草酸-盐酸体系中的水解情况进行了研究,并对不同条件下反应产物中葡萄糖的质量浓度进行了测定。依据纤维素酸水解反应特点,根据Seaman模型,对微晶纤维素在草酸盐酸体系中的水解动力学规律进行了研究。动力学结果:纤维素水解和葡萄糖降解的活化能分别是58.02 k J/mol和144.2 k J/mol。升高反应温度,使纤维素水解反应速度加快,也会使葡萄糖的降解速率加快。该模型的最佳反应条件是:固液比1∶20 g/m L,草酸的质量浓度25 g/L,盐酸的质量浓度1 g/L,温度90℃,时间9 h,在此条件下,葡萄糖质量浓度为1.657 g/L。 相似文献
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《应用化工》2016,(10)
对微晶纤维素在草酸-盐酸体系中的水解情况进行了研究,并对不同条件下反应产物中葡萄糖的质量浓度进行了测定。依据纤维素酸水解反应特点,根据Seaman模型,对微晶纤维素在草酸盐酸体系中的水解动力学规律进行了研究。动力学结果:纤维素水解和葡萄糖降解的活化能分别是58.02 k J/mol和144.2 k J/mol。升高反应温度,使纤维素水解反应速度加快,也会使葡萄糖的降解速率加快。该模型的最佳反应条件是:固液比1∶20 g/m L,草酸的质量浓度25 g/L,盐酸的质量浓度1 g/L,温度90℃,时间9 h,在此条件下,葡萄糖质量浓度为1.657 g/L。 相似文献
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从原料预处理技术、纤维素酶技术、水解发酵工艺以及原料的综合利用技术等几个方面,对制约木质纤维素乙醇的技术难点进行了分析与讨论。 相似文献
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Youngmi Kim Thomas Kreke Michael R. Ladisch 《American Institute of Chemical Engineers》2013,59(1):188-199
Hydrothermal pretreatment of lignocellulosic materials generates a liquid stream rich in pentose sugar oligomers. Cost‐effective hydrolysis and utilization of these soluble sugar oligomers is an integral process of biofuel production. We report integrated rate equations for hydrolysis of xylo‐oligomers derived from pretreated hardwood by dicarboxylic maleic and oxalic acids. The highest xylose yield observed with dicarboxylic acids was 96%, and compared to sulfuric acid, was 5–15% higher with less xylose degradation. Dicarboxylic acids showed an inverse correlation between xylose degradation rates and acid loadings unlike sulfuric acid for which less acid results in less xylose degradation to aldehydes and humic substances. A combination of high acid and low‐temperature leads to xylose yield improvement. Hydrolysis time course data at three different acid concentrations and three temperatures between 140 and 180°C were used to develop a reaction model for the hydrolysis of xylo‐oligosaccharides to xylose by dicarboxylic acids. © 2012 American Institute of Chemical Engineers AIChE J, 59: 188–199, 2013 相似文献
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木质纤维素是地球上最丰富的可再生生物质资源,其中纤维类多糖的酶催化降解是木质纤维素生物精炼的关键环节之一。对木质纤维素进行预处理,破坏底物的顽抗特性,是实现木质纤维素高效酶解糖化的必要途径。为此,各国学者围绕预处理技术开发以及底物顽抗特性开展了大量研究,本文对近几年来在这两方面取得的最新成果进行了综述和分析。在预处理方面,重点介绍了组合预处理、低温预处理、绿色溶剂与电化学预处理4类新型预处理技术,并对预处理效果与技术优势进行了评价;在底物顽抗特性方面,综述了木质素、结晶度、酶可及度等不同顽抗特性对纤维素酶解的影响规律,重点总结了近年来顽抗特性研究方面的新方法、新认识与新理解。上述研究成果有助于了解当前木质纤维素预处理研究的导向以及明确制约纤维素酶解的关键因素,为设计和筛选适宜的预处理方式、深刻理解纤维素酶解机制提供基础和指导。 相似文献
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本文研究了折流板厌氧反应器(ABR)在常温下处理低浓度有机废水有机污染物降解动力学方面的问题。根据对ABR反应器有机污染物降解动力学模型的研究,得出ABR处理效率与水力停留时间(HRT)、污泥浓度、分格数(m)及温度有关。小试采用葡萄糖配制的模拟生活污水进行试验,求得不同温度下减速增长的速度常数K2值。由Arrhenius公式求得了活化能E值1.92×104 J.mol-1,这表明本试验中温度对K2值影响不大,从而在理论上说明在温度较低时ABR反应器仍有较好处理效果的原因。 相似文献
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Rui Zhang Xuebin Lu Youshan Sun Xinying Wang Shuting Zhang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(2):306-314
BACKGROUND: Because of its high cost, nitric acid has not been widely employed as the catalyst for hydrolysis of lignocellulosic biomass to obtain fermentable sugars. However, recently more and more research results have reported that nitric acid was more effective than other acids for the hydrolysis of lignocellulose. Therefore, it is necessary to find an optimum condition for nitric acid pretreatment and a means of reducing the cost. RESULTS: In this work, low concentrations of nitric acid and short reaction times were considered to optimize the pretreatment process. The kinetic parameters of models to predict the concentrations of xylose, glucose, arabinose, acetic acid and furfural in the hydrolysates were obtained. Applying the kinetic models, the optimum conditions were: 150 °C, 0.6% HNO3 and 1 min, which yielded a solution containing up to 22.01 g L?1 xylose, 1.91 g L?1 glucose, 2.90 g L?1 arabinose, 2.42 g L?1 acetic acid and 0.21 g L?1 furfural, which were consistent with the predicted values. The influence of temperature was also studied using the Arrhenius equation. CONCLUSIONS: A combination of experimental data and model analysis suggested that 96% xylose yield can be achieved by using low concentration nitric acid for a short reaction time, which could greatly reduce the pretreatment cost. Therefore, dilute nitric acid could be considered a good choice for the hydrolysis of corn stover. Copyright © 2010 Society of Chemical Industry 相似文献
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采用微波辅助稀酸法对棉花秸秆进行水解糖化。探索了微波辐射温度、微波辐射时间、料液比及硫酸浓度对秸秆水解糖化效果的影响。结果表明,微波辅助棉花秸秆稀酸水解糖化的最佳糖化工艺条件为:微波辐射温度80℃,微波辐射时间50min,料液比1∶16g/mL,硫酸浓度3.0%。各影响因素对还原糖收率的影响顺序为:料液比微波辐射温度硫酸浓度微波辐射时间。在最佳糖化工艺条件下,还原糖收率为3.17%。 相似文献
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The effect of pH on the decomposition of peracetic acid in an aqueous solution was studied. It was found that three potential reactions, namely i) the spontaneous decomposition, ii) the hydrolysis and iii) the transition metal catalysed decomposition, are responsible for the consumption of peracetic acid. The spontaneous decomposition reaches its maximum at pH 8.2, while both the hydrolysis and metal ion catalysed decomposition increase as the pH increases. At pH 10.5 and higher, the hydrolysis becomes dominant when the metal ion catalysed decomposition is minimized by the addition of DTMPA. The kinetics of the peracetic acid hydrolysis was developed, which can very well predict the development of peracetic acid and hydrogen peroxide during the decomposition reaction. 相似文献
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木质纤维素转化为燃料乙醇的研究进展 总被引:26,自引:0,他引:26
以木质纤维素为原料生产燃料乙醇的生物转化方法包括预处理、酶水解和发酵过程,对这些过程中的技术进展以及解决现存问题的方法进行了评述。氨法爆破技术是较好的预处理方法,超声波、微波处理等新技术有助于改善酶水解。阐述了酶水解机理、纤维素酶的生产以及酶水解过程的优化方法。指出固定化酶糖化发酵技术在生物转化木质纤维原料技术中的前景广阔;选择合适的发酵方法,优化发酵过程,以及解决抑制问题对于提高乙醇产率尤为重要;利用基因重组技术构建旨在发酵混合糖的重组菌对于生产生物乙醇具有里程碑意义。 相似文献