乙醇脱水的木薯粉吸附性能研究

使用恒温固定吸附床对乙醇蒸汽脱水的术薯粉吸附剂的气相选择吸附性能进行研究。乙醇原料液的浓度为75％～95％（质量百分数）,使用干燥过的木薯粉作为吸4;什剂,分别测得吸附床不同位置处、不同表观速率、不同吸附剂粒度和不同温度时的乙醇蒸汽的透过曲线并进行了分析。通过木薯粉吸附最终可获得99．7％（质量百分数）的无水乙醇。     

乙醇脱水吸附剂吸附-脱附性能的研究

研究了乙醇脱水吸附剂对水和乙醇的气相吸附性能.在φ50 mm×700 mm的吸附柱中测定了乙醇脱水吸附剂吸附乙醇溶液中水的穿透曲线,考察了进料流速、进料浓度和床层高度对吸附穿透曲线的影响.采用热空气对吸附剂进行再生,测定了再生后吸附剂的穿透曲线,找出了最佳再生条件.用环境扫描电镜和热重-差示扫描量热分析仪对吸附剂的性质进行了表征.结果表明:吸附剂对水的吸附比乙醇强烈地多,可以选择性吸附水分,达到脱水目的.吸附剂吸水的最大吸附量可达20%,再生后的吸附剂对水仍有很好的吸附能力,体现了该吸附剂具有较高的工业应用价值.     

玉米粉吸附乙醇蒸气中的水

玉米粉能从乙醇蒸气中选择性地吸附水分,得到无水乙醇,并可在90～120℃的空气中再生,反覆循环使用,性能稳定。吸附穿透时间和床层高度关系符合Bohart Adams公式。     

浅谈从生物质制取液体燃料乙醇工艺

阐明了用生物质制体燃料乙醇的原因,提倡用清液发酵酒精,并采用耐高温酒精活性干酵母作为菌株,在酒精的提纯中采用盐溶精馏法,用无水硫酸钙进行酒精的气相脱水的办法和用株物作吸附剂的办法制取乙醇。     

燃料乙醇脱水工艺的研究与展望

伴随人类环境保护意识的进一步提升,清洁能源的应用逐渐普及化,乙醇燃料的脱水提纯处理工艺已成为清洁燃料应用的重要方面。基于此,本文在对乙醇燃料脱水工艺进行整体把握的基础之上,对燃料乙醇脱水主要工艺处理技术进行了详细介绍。     

我国甘薯生产燃料乙醇的工艺现状及脱水技术改进

介绍了我国甘薯生产燃料乙醇的必要性及其优势,详细介绍了甘薯燃料乙醇的工艺现状,并针对现行工艺中脱水技术的不足,通过实验探索提出一套完全由甘薯构成的燃料乙醇制备过程,重点改进了原工艺的吸附脱水技术,提高了甘薯的综合利用率,为工业化生产甘薯燃料乙醇的绿色工艺提供新思路.     

用于低碳混合醇吸附脱水的分子筛再生

低碳醇脱水是低碳醇分离的一个重要步骤。本文在实验的基础上，对用于低碳混合醇脱水的分子筛的热空气再生工艺及其残留醇的回收进行了阐述，给出了该分子筛经过数次热空气再生后，其吸水性能的劣化情况，并对热空气再生工艺所需的能耗进行了估算。本文结果为低碳混合醇等醇类的分子筛脱水的工艺计算和设计提供了必要的依据。     

乙醇脱水工艺改进

应用干燥的纳型阳离子交换树脂作工业乙醇脱水剂,并就接触时间,杂质来源等问题进行分析并提出改进意见,经实际应用,获提高收纺３０％,降低能耗３０％。     

生物质吸附剂在制备燃料乙醇中应用的研究进展

在最近的几十年中,由于能源短缺和环境恶化,生物质燃料乙醇（BFE）因为其所具有的可循环无污染的优点,引起了人们越来越多的关注。但是在生物燃料乙醇的制备过程中,存在着乙醇脱水工艺能量消耗过大的问题。因此优化乙醇脱水过程一直是人们研究的重中之重。本文简述了国内外吸附法分离乙醇和水工艺中使用的吸附剂,指出了生物质吸附剂在燃料乙醇中优于其它吸附剂的特点,重点分析了生物质吸附剂的研究成果及对其的改性研究。分析表明改性后吸附剂不但拥有良好的吸附效果,还可以在吸附操作结束后重新作为发酵制乙醇的原料,以实现资源的充分利用。最后展望了生物质吸附剂在制备燃料乙醇工艺中的发展趋势,即获得更优秀的脱水效果与更完善的循环利用过程。     

粉末活性炭吸附性能对比研究

通过测定不同活性炭的比表面积,和它们的荧光显微微观结构分析,以及它们对水体中常见的黄腐酸和苯酚两种不同分子大小的有机物吸附性能比较得知,活性炭对有机物的吸附量的大小不仅与其比表面积大小有关,而且还与它们的微孔结构大小和有机物分子结构的大小有直接的关系,为粉末活性炭在饮用水处理的应用提供一定的指导依据。     

IN SITU SEPARATION OF ETHANOL DURING BATCH FERMENTATION WITH CO_2 STRIPPING AND ACTIVATED CARBON ADSORPTION

In situ separation of ethanol during batch fermentation with CO_2 stripping and activated carbon adsorption was studied. The higher initial glucose concentration and fermentation rate were reached due to the elimination of ethanol inhibition on the cell growth by means of CO_2 stripping. The stripped ethanol vapor was selectively adsorbed by an activated carbon column. The conde(?)sate desorbed from the adsorption column can be higher than 50% by weight. Ar unstructured model was used to simulate the experimental data satisfactorily.     

陶瓷球吸附污水中低含量氨氮性能研究

针对污水中低含量的氨氮,考察在陶瓷生产过程中产生的陶瓷球的吸附性能.用静态吸附法测定氨离子在陶瓷球上的吸附等温线、了解动力学特性,并探讨pH、改性等方法对陶瓷球吸附氨氮的影响规律.结果表明,随着溶液中吸附质含量的上升,吸附剂的吸附容量明显上升,达到动态平衡的时间为7h;陶瓷球吸附氨氮的最佳pH在6～9,吸附方式有离子交换作用和物理吸附作用;使用NaCl溶液浸泡振荡的改性方法可明显提高陶瓷球对氨氮的吸附性能,成为一种有效且廉价的改性方法.证明陶瓷厂排出的废料陶瓷球可以应用于污水中低含量氨氮的吸附去除.     

MODEL FOR THE PREDICTION OF DEHYDRATION AND CALCINATION RATES OF BAYER PLANT GIBBSITE

A model for the prediction of rates of dehydration of Chemically Bound Moisture of Gibbsite is proposed. The theoretical dehydration rates evaluated from the model are compared with experimental values. The correlation between the experimental data and theoretically predicted values is found to be satisfactory. The curves obtained for differential thermal analysis of Gibbsite are found to resemble the DTA curves predicted theoretically using the proposed rate equations.     

MODEL FOR THE PREDICTION OF DEHYDRATION AND CALCINATION RATES OF BAYER PLANT GIBBSITE

A model for the prediction of rates of dehydration of Chemically Bound Moisture of Gibbsite is proposed. The theoretical dehydration rates evaluated from the model are compared with experimental values. The correlation between the experimental data and theoretically predicted values is found to be satisfactory. The curves obtained for differential thermal analysis of Gibbsite are found to resemble the DTA curves predicted theoretically using the proposed rate equations.     

OSMOTIC DEHYDRATION OF PINEAPPLE

The effects of sugar type, sugar concentration, immersion time and temperature on the mass transfer of osmotic dehydration were studied using pie shape slices (7 mm thick with its center cork thrown away) of fresh pineapple (Queen variety, 90% maturity). The dehydration process was performed using two type of sugar as an osmotic agent (glucose and sucrose), three levels of sugar concentration (50, 60, and 70%), three levels of temperature (30, 50, and 70 °C), and three levels of immersion time (3, 6, and 9 hours). Following the osmotic dehydration process, the pineapple was dried at 70 °C for 48 hours. The mass transfer was then calculated and analyzed statistically. Sugar type, concentration, temperature, and length of immersion, have a significant effect on the mass transfer of osmotically dehydrated pineapple. The highest mass transfer of pineapple was found by using sucrose at the concentration of 70%, temperature 50 °C and 9 hours of immersion time.     

酒精酵母固定化的研究

海藻酸钙固定化酵母球形颗粒经过Al~(3+)处理后,其机械强度提高一倍。用拉西环陶瓷填料作隐蔽及支撑物,海藻酸钙固定化酵母颗粒的机械强度即为拉西环陶瓷填料本身的机械强度,反应器的乙醇生产能力只降低了27％。本文考察了海藻酸钙固定化酵母与聚乙烯醇固定化酵母的连续乙醇发酵行为。     

THE DEHYDRATION OF ETHANOL BY EXTRACTIVE DISTILLATION

Ethanol dehydration has been accomplished by azeotropic distillation, reverse osmosis and silica get adsorption. This paper describes the use of extractive distillation as another alternative. Effective extractive agents presented include certain benzoates, anhydrides, alcohols and esters.     

A LUMPED KINETIC MODEL FOR DEHYDRATION OF ETHANOL TO HYDROCARBONS OVER HZSM-5

A kinetic model for the conversion of ethanol to hydrocarbons over HZSM-5 catalyst has been developed. The model is based on data from ethanol dehydration experiments conducted in a fixed-bed integral reactor at atmospheric pressure and temperatures of 150°C to 360°C, and is the first which integrates the major reaction pathways of both dehydration and higher hydrocarbon formation over ZSM-5 zeolite. In the model C₃-C₆ olefins, C₃-C₅ paraffins, and C₆⁺ hydrocarbons are treated as lumped species, while ethanol, diethyl ether, ethylene, and ethane are treated individually. Nonlinear parameter estimation using quasilinearization and least squares as the objective function has been implemented to estimate rate constants, adsorption equilibrium constants, and activation energies. The Langmuir-Hinshelwood rate expressions successfully correlated the experimental data.