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。     

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.     

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     

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%。     

微波合成氮杂环丁酮二硫代苯并噻唑的研究

采用微波辐射的方法,以2-巯基苯并噻唑为次磺酸捕捉剂,对青霉素G亚砜对-甲氧基苄基酯开环生成氮杂环丁酮二硫代苯并噻唑的反应条件进行优化。结果表明,最佳的反应条件为：青霉素G亚砜对-甲氧基苄基酯、2-巯基苯并噻唑物质的摩尔比为1∶1.1,甲苯10 mL,反应温度140℃,微波辐射功率720 W,辐射时间4 min,此时产率89.80%,与普通加热反应相比,反应时间缩短至4 min。     

Deep oxidative–extractive desulfurization of fuels using benzyl‐based ionic liquid

Four benzyl‐based ionic liquids (ILs) were synthetized and used for deep desulfurization of model oil and real diesel fuel. The removal efficiencies of benzothiophene (BT) and dibenzothiophene (DBT) with [Bzmim][NTf₂] and [Bzmim][SCN] as extractants are higher than that with [Bzmp][NTf₂] and [Bzmp][SCN] as extractants. The desulfurization capability follows the Nernst's Law. A reactive extraction mathematical model for desulfurization was established. An oxidative‐extractive two‐step deep desulfurization method was developed. DBT was first oxidized by H₂O₂ with CH₃COOH as catalyst and then the unoxidized DBT and uncrystallized dibenzothiophene sulfoxide (DBTO₂) in model oil were extracted by [Bzmim][NTf₂], and finally the removal efficiency was 98.4% after one‐stage extraction. Besides, the removal efficiency of 4,6‐DMDBT was 96.4% after oxidation and one‐stage extraction processes. Moreover, the oxidative‐extractive two‐step deep desulfurization method was also effective for desulfurization of diesel fuel. The removal efficiency of sulfur reached up to 96% after oxidation and three‐stage cross‐current extraction processes. © 2016 American Institute of Chemical Engineers AIChE J, 62: 4023–4034, 2016     

青霉素G亚砜的合成

以青霉素G钾盐为原料,采用15%左右低浓度过氧乙酸为氧化剂合成青霉素G亚砜,反应时间2～2.5h,n(过氧乙酸):n(青霉素G钾盐)=(1.1～1.2):1.0,反应温度和结晶温度在0～5℃,总收率可达96%以上。所得青霉素G亚砜可直接从溶液中结晶析出,解决了产物与反应体系的分离。产品纯度较高。     

Liquid–liquid extraction of Hg(II) from acidic chloride solutions using bis‐2‐ethylhexyl sulfoxide

The liquid–liquid extraction of Hg(II) from acidic chloride solutions has been studied using bis‐2‐ethylhexyl sulfoxide (B2EHSO) as an extractant. For comparison, extraction studies have also been carried out using di‐n‐octyl sulfoxide (DOSO) and diphenyl sulfoxide (DPhSO). The extraction data have been analysed by both graphical and theoretical methods taking into account aqueous phase speciation and all plausible complexes extracted into the organic phase. These results demonstrate that Hg(II) is extracted into xylene as HgCl₂.3R₂SO (where R₂SO represents the sulfoxide). The equilibrium constant of the extracted complex has been deduced by non‐linear regression analysis. The developed liquid–liquid extraction procedure has been applied for the recovery of mercury from the brine‐sludge of a Chlor‐Alkali plant. © 2001 Society of Chemical Industry     

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。     

Recovery of rare earth elements from simulated fluorescent powder using bifunctional ionic liquid extractants (Bif‐ILEs)

BACKGROUND: Numerous high purity ammonium‐type ionic liquid extractants have been prepared for engineering purposes. Bifunctional ionic liquid extractants (Bif‐ILEs) have been widely applied to separate and extract rare earths and metal ions with high extraction efficiencies and selectivities. In the present study, new Bif‐ILEs [A336][P204] and [A336][P507] have been used to extract rare earths from a simulated solution of a fluorescent powder in a high concentration of Al(NO₃)₃. RESULTS: Bif‐ILEs were prepared from Aliquat336 (A336) and the commercial organophosphorus acid extractants, P204 and P507. These extractants [A336][P204] and [A336][P507] have similar characteristics to neutral organophosphorus extractants. When these Bif‐ILEs were used to extract RE(III) from a simulated waste fluorescent powder system a third phase appeared which could be eliminated by the addition of 10% isopropanol modifier. The coexisting Al₂O₃ in the fluorescent powder was changed to a salting‐out agent (Al(NO₃)₃) in the extraction process and promoted the extraction efficiency of RE(III). Using a countercurrent extraction process at a phase ratio V_o:V_w = 4:1 and pH = 0.56, the RE(III) recovery reached 95.2% in 5–7 stages. Finally, the extractabilities of these bifunctional extractants were compared with the neutral organophosphorus extractants P350, TBP and Cyanex923 at different concentrations, initial pHs and temperatures. CONCLUSIONS: By comparison with other neutral organophosphorus extractants, Bif‐ILEs [A336][P204] and [A336][P507] can be considered efficient potential extractants for separating and recycling REEs and Al₂O₃ from waste fluorescent powder. Copyright © 2011 Society of Chemical Industry     

The adjustable synergistic effects between acid–base coupling bifunctional ionic liquid extractants for rare earth separation

Two of the most widely used industrial extractants for rare earth elements (REEs), that is, di(2‐ethylhexyl)phosphoric acid (HDEHP) and 2‐ethyl(hexyl) phosphonic acid mono‐2‐ethylhexyl ester (HEH[EHP]) were developed into [DEHP]^? type acid–base coupling bifunctionalized ionic liquids (ABC‐BILs) and [EHEHP]^? type ABC‐BILs, respectively. The combinations of ABC‐BIL extractants revealed synergistic effects for REEs. Seven different combinations of ABC‐BILs and five kinds of REEs confirmed the novel synergistic extraction. Some synergy coefficients of the combined ABC‐BILs were bigger than those of mixed HDEHP and HEH[EHP] by two orders of magnitude. The first synergistic extraction produced by ionic liquid extractants in the field of solvent extraction was reported in this article. The novel synergistic extraction from combined ABC‐BILs extractants revealed highly efficient and environmentally friendly potential in both of academic research and industrial application for REEs separation. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3859–3868, 2014     

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.     

Partitioning Behavior of Penicillin G in Aqueous Two Phase System Formed by Ionic Liquids and Phosphate

Abstract

An aqueous two‐phase system (ATPS) was presented with hydrophilic ionic liquid 1‐butyl‐3‐methylimidazolium chloride ([Bmim]Cl) and NaH₂PO₄ aqueous solution in this paper. The partitioning behavior of penicillin G in the ATPS was investigated. Concentrations of NaH₂PO₄, penicillin G, and [Bmim]Cl were evaluated to determine their effects on the partition coefficient and extraction yield of penicillin G. It was found that both of partition coefficient and extraction yield strongly depended on the concentration of [Bmim]Cl, penicillin and NaH₂PO₄. A high extraction yield of 93% was achieved with the following parameters: NaH₂PO₄ · 2H₂O 40% (wt%), penicillin 45000～50000 u/ml, [Bmim]Cl 20～21% (wt%). The [Bmim]Cl/NaH₂PO₄ system was also applied in a real filtration of penicillin G fermentation broth and the extraction yield was averaged at 91.5%. It is worthy noting that the working pH value of ATPS was at the range of 5～6, no emulsification and protein denaturation could be observed.     

Reversed micelle synergistic extraction from phosphonium ionic liquid extractants in diluent for rare earth

The first synergistic extraction between quaternary phosphonium type ionic liquid extractants in toluene for rare earth was reported in this article. There were two different ion‐association mechanisms in the synergistic extraction system. The formed reversed micelles contributed to increase extractability of the synergistic extraction system to a considerable extent. On the one hand, million tons of saponification wastewater from acidic extractants may be avoided by developing the extraction system using bifunctional ionic liquid extractants. On the other hand, the novel synergistic extraction offers an effective strategy to increase the extractabilities of industrial extractants. This article reveals sustainable and efficient potentials for industrial rare earth separation. © 2016 American Institute of Chemical Engineers AIChE J, 62: 2163–2169, 2016     

Reactive extraction of propionic acid using tri‐n‐octylamine,tri‐n‐butyl phosphate and aliquat 336 in sunflower oil as diluent

BACKGROUND : Propionic acid is widely used in chemical and allied industries and can be produced by biocultivation in a clean and environmentally friendly route. Recovery of the acid from the dilute stream from the bioreactor is an economic problem. Reactive extraction is a promising method of recovering the acid but suffers from toxicity problems of the solvent employed. There is thus a need for a non‐toxic solvent or a combination of less toxic extractants in a non‐toxic diluent that can recover acid efficiently. RESULTS: The effect of different extractants (tri‐n‐butylphosphate (TBP), tri‐n‐octylamine (TOA) and Aliquat 336) and their mixed binary solutions in sunflower oil diluent was studied to find the best extractant‐sunflower oil combination. Equilibrium complexation constant, K_E, values of 4.02, 3.13 and 1.87 m³ kmol^?1 were obtained for propionic acid extraction using Aliquat 336, TOA and TBP, respectively, in sunflower oil. The effect of different modifiers (1‐decanol, methylisobutyl ketone, butyl acetate and dodecanol) on the extraction was also studied and it was found that modifiers enhance extraction, with 1‐decanol found to be the best. CONCLUSION: The problem of toxicity in reactive extraction can be reduced by using a non‐toxic diluent (sunflower oil) or a modifier in a non‐toxic solvent, with the extractant. The addition of modifiers was found to improve the extraction. Copyright © 2008 Society of Chemical Industry     

Nucleation Kinetics and Growth Model of Penicillin Sulfoxide in Butyl Acetate

Nucleation kinetics and a growth model of penicillin sulfoxide in butyl acetate were studied. Nucleation parameters such as energy per unit volume, radius of critical nucleus, critical free energy barrier, and nucleation rate were evaluated. A laser method was selected to detect the first crystal in induction period studies. By means of scanning electron microscopy and surface entropy factor, the growth model of penicillin sulfoxide developed from butyl acetate could be determined.     

Reactive extraction of itaconic acid using tri‐n‐butyl phosphate and aliquat 336 in sunflower oil as a non‐toxic diluent

Itaconic acid finds a place in various industrial applications. It can be produced by biocultivation in a clean and environment friendly route but recovery of the acid from the dilute stream of the bioreactor is an economic problem. Reactive extraction is a promising method to recover carboxylic acid but suffers from toxicity problems of the diluent and extractant employed. So there is need for a non‐toxic extractant and diluent or a combination of less toxic extractants in a non‐toxic diluent that can recover acid efficiently. Effect of different extractants: tri‐n‐butylphosphate (TBP) (an organophosporous compound) and Aliquat 336 (a quaternary amine) in sunflower oil was studied to find the best extractant–sunflower oil combination. Equilibrium complexation constant, K_E, values of 1.789 and 2.385 m³ kmol^?1, respectively, were obtained for itaconic acid extraction using TBP and Aliquat 336 in sunflower oil. The problem of toxicity in reactive extraction can be reduced by using a natural non‐toxic diluent (sunflower oil) with the extractant. Copyright © 2010 Society of Chemical Industry     

Extraction Chromatography Versus Solvent Extraction: How Similar are They?

Abstract

Over the last decade, extraction chromatography (EXC) has emerged as a versatile and effective method for the separation and preconcentration of a number of metal ions. Frequently, EXC is described as a technique that combines the selectivity of solvent extraction (SX) with the ease of operation of chromatographic methods. Despite this, the extent to which EXC actually provides the selectivity of SX and to which solvent extraction data can be used for the quantitative prediction of the retention of metal ions on an EXC column has remained unclear. To address these questions, the extraction chromatographic and solvent extraction behavior of lanthanides using three different acidic organophosphorus extractants bis‐(2‐ethylhexyl) phosphoric acid (HDEHP), 2‐ethylhexyl 2‐ethylhexylphosphonic acid (HEH[EHP]), and bis‐(2,4,4 trimethylpentyl)phosphinic acid (H[DTMPeP])) have been compared. Specifically, the rate and extent of uptake of selected lanthanides by the three extractants have been examined. In addition, the relationship between the volume distribution ratios obtained in the chromatographic and liquid–liquid extraction modes have been compared and their utility in predicting the chromatographic parameter, k′, the number of free column volumes to peak maximum determined.     

铂族金属萃取剂杂环取代基亚砜的合成

采用硫醚氧化法合成了异戊基苯并噻唑亚砜(ABSO),并进行了红外光谱分析,目的产物收率为83.6%。研究了异戊基苯并噻唑亚砜萃取钯的性能,用0.5mol.L-1ABSO从0.1mol.L-1HCl、浓度为100mg.L-1的Pd(2+)溶液中萃取钯,一次萃取率可达到99.7%。     

Separation mechanisms of citric and itaconic acids by water‐immiscible amines

The selective separation of citric and itaconic acids by amine extractants was studied. The stoichiometry of the carboxylate:amine complexes was established by various independent experimental techniques. Loading and distribution curves as well as FT–IR and fluorescence spectra were recorded. Tri‐n‐octyl amine in 1‐octanol was selective for the stronger carboxylate, citrate. Acid–base coupled extractants composed of di‐(2‐ethylhexyl) phosphoric acid and methyltriocyl ammonium cation in dichloromethane formed reverse micelles with uncharged surfaces. This extractant was selective for the more hydrophobic itaconate, which is located in the apolar envelope of the reverse micelle. Citrate was located in the aqueous inner core bound to the ammonium cation. The roles of amine salt, the diluent and of water‐immiscible additives on the selectivity of the extraction are discussed. © 1999 Society of Chemical Industry