青霉素亚砜结晶生长与成核动力学

利用Mydlarz 和 Jones 模型（MJ2）,对乙酸丁酯中青霉素亚砜的成核与生长动力学进行研究。通过矩量法对MJ2模型进行处理后,利用晶体产品的粒度分布计算得到青霉素亚砜的生长速率与成核速率,然后利用最小二乘法拟合回归求解出成核与生长动力学方程参数。通过实验设计考察了过饱和度、温度与搅拌速度对青霉素亚砜晶体成核和生长过程的影响。研究表明青霉素亚砜晶体生长速率随过饱和度比的增加呈现指数型增长,确定青霉素亚砜晶体生长属于晶体表面生长控制过程。由于高速搅拌会增加青霉素亚砜晶体的破碎,促进了二次成核过程,随着搅拌速度的增加,晶体生长速率出现小幅下滑,而成核速率则明显升高。青霉素亚砜成核与生长动力学研究将有助于工业生产过程优化。     

醋酸丁酯及二正辛基亚砜萃取青霉素的研究

通过化学分析、计算机数据处理及FT—IR红外光谱的确证,提出了醋酸丁酯及二正辛基亚砜萃取青霉素的萃合反应式及萃合物的键合结构;研究中观察到青霉素在醋酸丁酯中形成了反胶团,胶团半径可达0.6μm.     

Improved extraction of penicillin G using hydrocarbon sulfoxides

Extraction of penicillin G with sulfoxide extractants, petroleum sulfoxide (PSO) and di‐isooctyl sulfoxide (DISO) was researched systematically. Based on research of the extraction equilibrium of penicillin G, the suitable extraction and re‐extraction conditions were determined, and then extraction cascade and bench‐scale experiments were carried out. The performance of extraction systems composed of PSO and DISO, with sulfonated kerosene as the diluent, is superior to that of n‐butyl acetate owing to the low solubility of these new extractants in water. Their consumption during the extraction process was lower, and the recovery step of extractants from aqueous raffinate was eliminated. Copyright © 2004 Society of Chemical Industry     

脂肪醇类溶剂对青霉素的萃取

研究了不同醇类及醇酯混合体系对青霉素的萃取. 在pH=4的条件下脂肪醇及醇酯混合体系的萃取能力均高于乙酸丁酯. 具有相同碳原子数、带支链的脂肪醇对青霉素的萃取能力比直链醇强,平衡后的有机相水含量下降. 红外光谱分析表明：乙酸丁酯的加入使脂肪醇羟基谱带变宽且明显向高波数方向位移,能阻止醇的多聚,使羟基活性增强. 激光拉曼光谱结果证明：青霉素是以反相微乳液的形式进入脂肪醇相的;支链的存在使体系的有序性和极性都明显增加.     

Modeling the effect of mixed emulsifier systems in emulsion copolymerization

A mathematical model for the emulsion copolymerization of methyl methacrylate and butyl acrylate has been developed. This model, which applies the method of moments of a distribution to model the evolution of the particle size distribution, predicts the effects of the concentration and composition of anionic/nonionic surfactant systems on the polymerization process and on the characteristics of the product obtained, including particle nucleation, growth, and coagulation. Nucleation is a dynamic process in which the surfactant system affects the competition between homogeneous and heterogeneous nucleation, with simultaneous coagulative processes of precursor particles. The effect of the surfactant system on nucleation is described mathematically using a variable radical critical chain length, j_cr. The solution properties of surfactant mixtures, mainly critical micelle concentration and micelle composition, were predicted using the thermodynamics of nonideal mixtures. A good agreement between model predictions in batch and semicontinuous reactors and experimental results was found. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 445–458, 1997     

体相光催化处理有机废水新工艺

针对工业废水浓度和色度高、光线在废水中的穿透能力有限、催化剂极易中毒等因素,本文以球形微波无极灯为“点光源”填充反应器构建“体光源”,提出体相光催化反应的设想,探索光催化处理工业废水的过程强化作用。分别以甲基橙溶液和含2,4-二氯酸农药废水为研究对象,探索体相光催化反应过程中有机污染物的降解性能;以乙醇水溶液和青霉素废酸水为研究对象,探索体相光催化反应过程热效应与光催化在废水处理中的耦合作用。结果表明,体相光催化反应不仅可以有效地降解水溶液中有机物,2,4-二氯酸农药废水COD_Cr去除率达到83.9%,而且利用反应器运行过程中的热效应能够100%地分离回收青霉素废酸水中的乙酸丁酯,同时去除55.8%的COD_Cr。因此,填充床式体相光催化反应系统能够将微波能、光催化和热效应集成于一体,在实现光催化技术处理有机废水及资源化的实际应用方面有积极意义。     

Partition Behavior of Penicillin in Three-liquid-phase Extraction System

Partition behavior of penicillins G and V was studied in a novel three-liquid-phase extraction system, which is composed of butyl acetate (BA), polyethylene glycol (PEG), ammonia sulfate [(NH4)2SO4] and water (H2O). The main components in the top, middle and bottom phases are butyl acetate, polyethylene glycol aqueous solution and ammonia sulfate aqueous solution, respectively. Some parameters such as partition coefficients Di/j and mass fractions Ei of penicillins G and V were determined at the room temperature, respectively. Experimental efforts have been made to investigate the partition behavior of penicillin in the three-liquid-phase extraction system, including initial concentrations of phase-forming components [PEG and (NH4)2SO4], PEG molecular weight, pH, initial concentration of penicillin. The results indicated that penicillins G and V have the similar partition behavior. They preferentially distribute into the middle phase with the increase of initial concentration of phase-forming components and into the top phase with the decrease of pH, while partition coefficient Dm/b is hardly affected by pH value. The variation of PEG molecular weight has little effect on mass fractions of penicillin. The increase of initial concentration of penicillins G and V could lead to the increase of Dt/b, Dm/b and the decrease of Dt/m, while their mass fractions in all phases were almost independent on their initial concentrations.     

青霉素发酵液直接氧化制备青霉素G亚砜反应条件优化

以过氧乙酸为氧化剂，研究了青霉素发酵液直接氧化制备青霉素G亚砜的过程，考察了不同影响因素对青霉素G亚砜转化率的影响，分析了氧化后菌丝中青霉素残留，建立并优化了青霉素发酵液直接氧化工艺。结果表明，搅拌转速、反应温度、过氧乙酸投料量、过氧乙酸浓度等因素是青霉素G亚砜转化率的关键影响因素，其他因素对青霉素发酵液直接氧化过程影响较小。过氧乙酸直接氧化青霉素发酵液可释放出残留在菌丝体内的青霉素，相比氧化青霉素G钾盐的转化率更高。最佳氧化工艺条件为反应温度5~10℃，搅拌转速100 r/min，30 min匀速加入青霉素摩尔量1.3倍的高浓度过氧乙酸，继续搅拌反应10 min。青霉素G亚砜的转化率可达98.6%，比青霉素G钾盐为原料的转化率提高1.2%。     

青霉素G亚砜二苯甲酯的合成研究

以青霉素G钾为原料制备青霉素G亚砜二苯甲酯。氧化反应优化条件为:n(过氧乙酸)∶n(青霉素G钾)=1.2∶1.0,氧化温度0～5℃,反应时间2h,青霉素G亚砜酸收率为97.3%;酯化反应优化条件为:二氯甲烷的用量为17mL/g青霉素G亚砜,投料比n(二苯甲醇)∶n(青霉素G亚砜)=1.8∶1.0,反应温度为-15℃,反应时间为60min,酯化收率为79.5%,反应总收率为77.4%。此工艺成本低廉,操作安全简便,对工业化生产具有积极意义。     

1，2-环己二醇溶解度的测定及关联

采用激光监视技术测定了1,2-环己二醇在乙酸甲酯、乙酸乙酯、乙酸丙酯、乙酸丁酯、丙烯酸甲酯、丙烯酸乙酯、甲基丙基酮、乙酰乙酸乙酯和水中的溶解度,并用UNIFAC模型进行了关联,其溶解度预测值与实测值吻合良好.     

Solid-Liquid Equilibria of trans-1,2-Cyclohexanediol＋Butyl Acetate＋ Water Ternary System

Using a laser observation technique,the solubilities of trans-1,2-cyclohexanediol in butyl acetate＋wa- ter were measured at the temperature range from 298.15K to 323.15K by a synthetic method at atmospheric pres- sure.It is shown that the solubilities of trans-1,2-cyclohexanediol in butyl acetate＋water were affected greatly by the proportion of butyl acetate and water,and presented maximum value at given temperature.The UNIFAC model was used to correlate the experimental data.The average relative deviation（ARD）between experimental and calculated values is 3.03%.     

Coproduction of Ethyl Acetate and n‐Butyl Acetate by Using a Reactive Dividing‐Wall Column

The performance of the reactive distillation dividing‐wall column for coproduction of ethyl acetate and butyl acetate was experimentally studied. n‐Butanol and ethanol are raw reaction materials that react with acetic acid in the reaction zone to produce n‐butyl acetate and ethyl acetate, respectively. n‐Butyl acetate is not only a product, but also acts to remove water generated by the esterification reactions. The effects of various parameters, such as catalyst loading per stage, reflux ratio, liquid split and molar feed ratios, ethyl acetate/n‐butyl acetate purity, pressure drop, and total energy consumption, are investigated. Results show that ethanol could be completely converted and the products could be easily separated, which shows great industrial application potential in the coproduction of ethyl acetate and n‐butyl acetate.     

反式-1,2-环基二醇+乙酸丁酯+水三元体系固液相平衡(英文)

Using a laser observation technique,the solubilities of trans-1,2-cyclohexanediol in butyl acetate+wa- ter were measured at the temperature range from 298.15K to 323.15K by a synthetic method at atmospheric pres- sure.It is shown that the solubilities of trans-1,2-cyclohexanediol in butyl acetate+water were affected greatly by the proportion of butyl acetate and water,and presented maximum value at given temperature.The UNIFAC model was used to correlate the experimental data.The average relative deviation(ARD)between experimental and calculated values is 3.03%.     

Effects of solvent polarity on the reaction of phenol with tolylene‐2,4‐diisocyanate

Using tolylene‐2,4‐diisocyanate as standard compound, the relationship between ? NCO absorbance and concentration was studied with in situ FTIR. The linear relationship appeared correct only for concentrations lower than 0.4 mol L^?1. Then, the urethane reaction kinetics of phenol with tolylene‐2,4‐diisocyanate were investigated in different solvents, such as dimethyl sulfoxide, cyclohexanone, n‐butyl acetate, 1,4‐dioxane, and xylene. It showed that solvents largely affected reaction rates. The reaction was largely accelerated in polar solvents, following the order of dimethyl sulfoxide > cyclohexanone > n‐butyl acetate > 1,4‐dioxane > xylene. It was in contrast to the alcohol–diisocyanate reaction. Finally, an appropriate reaction mechanism was proposed. The H? O bond in phenol was polarized under the influence of solvents, which made the combination of hydrogen to nitrogen and alkoxyl group to carbenium easier. After that the solvent was dissociated and the carbamate generated. The kinetic equation could be derived as v = k′K·[S:] [ROH]·[R′NCO]. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

青霉素G亚砜对-硝基苄酯的合成

青霉素G亚砜对—硝基苄酯是合成GCLE的重要中间体 ,可通过以青霉素G为原料 ,用低浓度过氧乙酸氧化 ,再以对—硝基苄氯进行羧基保护获得。本方法既能确保产品质量 ,又有利于安全生产 ,适合于工业化生产     

Polymorphism and crystal transformation of penicillin sulfoxide

Penicillin sulfoxide is the intermediate for the synthesis of 7-amino-3-desacetoxycephalosporanic acid which is one of the most important nucleuses of cephalosporin antibiotic. In this contribution, two crystal structures of penicillin sulfoxide (forms I and II) were determined by X-ray diffraction, and their thermotropic properties were investigated by differential scanning calorimetry (DSC). Furthermore, the transformation of form II to form I was studied quantitatively by Raman spectroscopy, and its rates at different temperatures were determined. The results indicate that penicillin sulfoxide is more stable as form I, and the temperature plays an important role in the crystal transformation.     

醋酸仲丁酯生产工艺的选择及应用

<正>丁烯法和醇酸酯化法是目前合成醋酸仲丁酯的主要的两种工艺,并且都有工业应用。通过对两种生产工艺的对比,正丁烯法具有工艺技术先进、投资少、能耗低、环境污染小等优点,加之延长石油某企业丰富的原料资源,是目前合成醋酸仲丁酯的主要生产工艺。     

改性片麻岩为催化剂合成有机羧酸酯的研究

以改性片麻岩为催化剂合成了醋酸乙酯、醋酸丁酯、醋酸戊酯、醋酸庚酯、醋酸苄醇酯、己酸乙酯、氯乙酸异丙酯和丙烯酸 2 乙基 己醇酯 ,其收率都在 90 %以上。合成醋酸丁酯 ,催化剂重复使用 9次 ,其收率仍达 92 %～ 99% ;催化剂的寿命达 489h ,醋酸丁酯收率仍不低于 92 %。     

乙酸乙酯与乙酸正丙酯的切换式连续生产

作者在对乙酸乙酯、乙酸异丙酯、乙酸正丙酯和乙酸丁酯的现有生产工艺进行分析后,以乙酸乙酯和乙酸正丙酯为研究对象,在以往对两者研究的基础上,提出了乙酸乙酯与乙酸正丙酯切换式连续生产的工艺流程,并且通过模拟计算和小试验证证明,在同样的生产装置上,可以分别连续生产乙酸乙酯和乙酸正丙酯,采用该工艺生产乙酸乙酯能耗低于传统工艺12%,生产乙酸正丙酯比原有工艺可以提高收率2%。     

Cu/ZnO/Al_2O_3催化剂用于醋酸仲丁酯加氢制备仲丁醇联产乙醇

采用固定床反应器,研究共沉淀法制备的Cu/ZnO/Al_2O_3催化剂用于醋酸仲丁酯催化加氢制备仲丁醇联产乙醇的催化性能,并考察反应温度、氢酯物质的量比、反应压力和空速对反应的影响。结果表明,Cu/ZnO/Al_2O_3催化剂表现出优良的催化性能,在反应温度210℃、氢酯物质的量比15、反应压力4.0MPa和空速1.0h-1条件下,醋酸仲丁酯转化率大于99%,仲丁醇选择性大于99%,乙醇选择性大于97%。推测Cu/ZnO/Al_2O_3催化剂上醋酸仲丁酯加氢制备仲丁醇联产乙醇的反应网络,仲丁醇与乙醇的脱氢反应和脱水反应、烯烃饱和加氢反应和酯交换反应是该体系在Cu/ZnO/Al_2O_3催化剂上存在的主要副反应。