Recovery of alpha-ketoglutaric acid from model fermentation broth using electrodialysis with bipolar membrane

ABSTRACT

A bipolar (BP) membrane electrodialysis (EDBM) was used to recover the alpha-ketoglutaric acid (AKG) from the model broth. A two-chamber EDBM membrane stack consisting of an anion exchange membrane and a BP membrane was used. The effect of the initial composition, applied current density, and pH of diluate on the efficiency of EDBM processes was investigated. The obtained results showed that the used membrane stack configuration allows complete separation of AKG from glucose and ethanol and simultaneous conversion of AKG salts to the acidic form. The scale-up of the EDBM process for model fermentation broth was also carried out.     

The Concentration of Organic Acids in Cranberry Juice Modulates the Gut Microbiota in Mice

A daily consumption of cranberry juice (CJ) is linked to many beneficial health effects due to its richness in polyphenols but could also awake some intestinal discomforts due to its organic acid content and possibly lead to intestinal inflammation. Additionally, the impact of such a juice on the gut microbiota is still unknown. Thus, this study aimed to determine the impacts of a daily consumption of CJ and its successive deacidification on the intestinal inflammation and on the gut microbiota in mice. Four deacidified CJs (DCJs) (deacidification rates of 0, 40, 60, and 80%) were produced by electrodialysis with bipolar membrane (EDBM) and administered to C57BL/6J mice for four weeks, while the diet (CHOW) and the water were ad libitum. Different parameters were measured to determine intestinal inflammation when the gut microbiota was profiled. Treatment with a 0% DCJ did not induce intestinal inflammation but increased the gut microbiota diversity and induced a modulation of its functions in comparison with control (water). The effect of the removal of the organic acid content of CJ on the decrease of intestinal inflammation could not be observed. However, deacidification by EDBM of CJ induced an additional increase, in comparison with a 0% DCJ, in the Lachnospiraceae family which have beneficial effects and functions associated with protection of the intestine: the lower the organic acid content, the more bacteria of the Lachnospiraceae family and functions having a positive impact on the gut microbiota.     

Evaluation of recovery characteristic of acidic and alkaline solutions from NaNO3 using conventional electrodialysis and electrodialysis with bipolar membranes

We compared the electrodialysis performance for HNO₃ and NaOH recovery from NaNO₃ solution by conventional electrodialysis (ED) and electrodialysis with bipolar membranes (EDBM) at constant current and constant voltage. The individual resistances of the components of the electrodialysis systems were also evaluated. The electrodialysis extent for HNO₃ and NaOH recovery from NaNO₃ solution was almost proportional to the total amount of electricity supplied to the system, regardless of the operation mode and the electrodialysis systems. For the same volume of feed solution, the energy consumption and current efficiency differed depending on the operation mode and the electrodialysis system. In both the ED and EDBM systems, the conductivity of the feed solution strongly affected the overall cell resistance after approximately 50% of the ions in the feed solution had migrated.     

电渗析分离乙二醛与硝酸的过程研究

在硝酸氧化乙醛制备乙二醛的过程中,需要除去产品中未反应的硝酸。常规的处理工艺容易引起硝酸再次发生氧化反应,因此需要探索新的脱酸技术。文中对电渗析法分离乙二醛溶液中的硝酸进行了实验研究,筛选了3种均相离子交换膜进行实验,使用筛选出的J-1-18离子交换膜组装电渗析装置进行分离过程的工艺条件研究。实验研究了膜堆电压对硝酸脱除率的影响和操作电压对电流效率的影响,考察了硝酸初始质量分数对电渗析分离的影响。研究结果表明:电渗析在低电压下操作,电流主要用于硝酸根离子的迁移,可实现硝酸的有效分离,且分离硝酸所用时间短,还有利于分别回收硝酸和乙酸。     

Design and study of a novel ammonia-based CO2 capture process with bipolar membrane electrodialysis

Aqueous ammonia is a promising absorbent in the field of post combustion CO₂ capture. However, the high volatilization of NH₃ results in a high energy requirement, as well as solid precipitation during the CO₂ regeneration process. A novel process was designed to reduce energy consumption and solve the problem. The bipolar membrane electrodialysis (EDBM) unit and CO₂ regeneration reactor were taken as the regeneration part. In the novel process, the bubble in the EDBM unit would be eliminated, and the regeneration of CO₂ and aqueous ammonia would be operated separately, which significantly reduced energy consumption and avoided the risk of precipitation during regeneration. According to the simulation and calculation results, the CO₂ regeneration energy consumption of the novel process using H₂SO₄ for CO₂ regeneration is 39.0% lower than that of the conventional ammonia-based process, which shows good energy saving potential. Moreover, the novel process will be more competitive as membrane technology develops.     

Structural effects of ion‐exchange membrane on the separation of L‐phenylalanine (L‐Phe) from fermentation broth using electrodialysis

The effects of membrane structure on the separation of L ‐phenylalanine (L ‐Phe) by electrodialysis from a fermentation broth and on the fouling tendency were investigated in this study. Two anion‐exchange membranes (Neosepta AFX and AM‐1, Tokuyama, Japan) were selected and characterized using the chronopotentiometry method. For a fresh membrane, AFX showed a lower electrical resistance and a lower permselectivity than AM‐1. After being fouled with humic acid, however, the electrical resistance of AFX was higher than that of AM‐1. The L ‐Phe selectivities for both membranes were lower than those of the fresh membranes. The result may be attributed to the structural difference between AFX and AM‐1 membranes. AFX has a lower repulsion force against the co‐ion and could be more strongly affected by the foulants than AM‐1 because AFX has a more porous structure than AM‐1. Experiments on the separation of L ‐Phe from the fermentation broth were carried out using two different stack configurations, ie desalting electrodialysis and water‐splitting electrodialysis. It was observed that the recovery efficiency of L ‐Phe through electrodialysis for 100 min reached 95% for AFX and 85% for AM‐1. In the desalting configuration of electrodialysis, the solution pH must be adjusted to alkaline conditions to recover the L ‐Phe through the anion‐exchange membrane. On the contrary, it was possible to recover the L ‐Phe without adjustment of the solution pH in the water‐splitting electrodialysis because OH^? generated from the bipolar membrane converted neutral L ‐Phe into an anion. © 2002 Society of Chemical Industry     

Asymmetric bipolar membrane electrodialysis for acid and base production

Bipolar membrane electrodialysis (BMED) is a promising technique for upgrading traditional manufacturing procedures and achieving a circular economy. However, the industrial applications of BMED technology have been restricted by the large consumption of expensive bipolar membranes and the unmatching behavior between water splitting and ion migration. Herein, we proposed a novel asymmetric bipolar membrane electrodialysis (ABMED) to regulate the water splitting in the bipolar membrane and orientational ion migration in the electrodialysis (ED). It was found that the ABMED exhibited comparable performances to BMED for acid/base production when the area of the bipolar membrane was reduced to 50% of the monopolar membrane. The total process cost of ABMED was 0.78 $/kg NaOH, which is 21% lower than the BMED process. The asymmetric membrane design was capable to boost the water splitting in the bipolar membrane and to eliminate the concentration polarization in the ED process.     

Lactic acid recovery from fermentation broth using one‐stage electrodialysis

One‐stage electrodialysis (ED) for lactic acid recovery with two‐ and three‐compartment water‐splitting ED (WSED) was investigated using various ion‐exchange membranes in order to overcome the inefficiency of two‐stage ED, which consists of desalting ED for recovery and partial purification and subsequent WSED for acidification. The two‐compartment WSED had a low current efficiency and high energy consumption in spite of a simple stack configuration. A three‐compartment WSED successfully converted sodium lactate in the fermentation broth into lactic acid and sodium hydroxide with average yields of 96% and 93%, respectively. In relation to lactic acid purification, of the membranes tested in this study, the highest glucose rejection, 98.3%, was achieved using a PC 100D membrane. The CMS membrane rejected magnesium and calcium at levels as high as 81.7% and 78.5%, respectively. We concluded that the three‐compartment WSED with properly chosen membranes, enabled lactic acid to be recovered directly from the fermentation broth. © 2001 Society of Chemical Industry     

Nitric acid and sodium hydroxide generation by electrodialysis using bipolar membranes

An electrodialysis process with bipolar membranes was used to generate HNO3 and NaOH from NaNO3 which can be found in industrial waste waters. The current efficiency of this process is limited by proton leakage through the anion exchange membrane (AEM), co-ion leakage through bipolar membranes (BPM) and water transport through the ion exchange membranes. Three cell configurations using three or two compartment cells with different anion or cation exchange membranes (CEM) in stack series were used and compared. Electrodialysis with three compartments gives the best current efficiencies for nitric acid and sodium hydroxide production from sodium nitrate.     

Preparation of mineral source water from deep sea water: Reduction of sulfate ion using selemion ASV membrane

Adopting a laboratory‐scaled electrodialysis (ED) process, we investigate the performance of a monovalent anion exchange permselective membrane in the reduction of the concentration of sulfate ions during the production of mineral source water from deep sea water (DSW). The dependence of the separation efficiency of anions on the operating time and the applied DC voltage is investigated based on a brine having salinity of about 15% prepared from DSW. The experimental results reveal that if the applied DC voltage is high, the change in the liquid volume during ED is dominated by the ions transported and the effect of electroosmosis. In addition, the amount of chloride ions transported correlates roughly linearly with the operating time, and the transport of sulfate ions is found to be blocked by chloride ions, presumably because of that the pore size of the permselective layer is close to the size of sulfate ions. © 2010 American Institute of Chemical Engineers AIChE J, 2011     

双极膜电渗析脱除苏氨酸母液中硫酸盐

采用三室双极膜电渗析脱除苏氨酸母液中硫酸盐,探讨连续操作对电渗析器性能变化的影响,并测定连续实验前后离子交换膜的面电阻,考察膜污染情况. 结果表明,苏氨酸母液中盐转化率达97%,酸室中得到0.50 mol/L的H+,碱室中得到0.53 mol/L的OH-,以阳离子计算的电流效率为60.33%,能耗为229.37 kW×h/kmol;随批次增加、操作时间延长,单位膜通量能耗和膜堆平均电阻增大,电流效率和膜通量减小,电渗析器性能下降;连续操作后,阴膜面电阻较使用前增加1.77 Ω×cm2,升高44.8%,双极膜面电阻增加0.91 Ω×cm2,升高19.5%,离子交换膜被污染.     

Bipolar membrane electrodialysis for cleaner production of N-methylated glycine derivative amino acids

In this study, cleaner production of N-methylglycine (NMG), N,N-dimethylglycine (DMG), and N,N,N-trimethylglycine (TMG) with similar structures but different methylate groups was performed using bipolar membrane electrodialysis (BMED). The effects of the feed mass concentration and current density on the separation performance were intensively analysed in terms of the molecular size, molecular structure, ion concentration, and interaction between amino acids and membranes. The results indicated that the optimal recovery performance was achieved at a current density of 200 A/m² and feed mass concentration of 6%. Under the optimal conditions, the energy consumption and current efficiencies were 2.3 kWh/kg and 78% for NMG, 2.49 kWh/kg and 69.5% for DMG, and 3.52 kWh/kg and 39.6% for TMG, respectively. It was speculated a competition for water splitting occurs between the bipolar membranes and anion exchange membranes when BMED is used for the separation and purification of large-sized bioproducts.     

Electrodialytic removal of nitrates and hardness from simulated mixtures using ion‐exchange membranes

A novel electrodialysis (ED) pilot plant unit coupled with a membrane stack containing 11 cation‐exchange and 10 anion‐exchange membranes is used for the removal of nitrates and hardness from simulated aqueous mixtures containing salts that are usually encountered in brackish water. The removal of high nitrates and water hardness is performed in 150 min of ED under three constant applied voltages at room temperature. The limiting current density is obtained for sodium nitrate and calcium chloride mixtures in dilute solution. In order to check the efficacy of the ED method, parameters like the applied potential are varied at constant flow rates. The efficiency of the ED method depends on the applied potential. Possible applications of ED are discussed for the removal of contaminants below the minimum contaminant level of drinking water. The ED method used here is satisfactory to produce good quality drinking water from a simulated mixture by removing the unwanted ions. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1788–1794, 2006     

Microencapsulation of passion fruit (Passiflora) juice with n-octenylsuccinate-derivatised starch using spray-drying

Food microencapsulation has been an efficient way of raising food shelf life during storage. In this work passion fruit juice was encapsulated with n-octenylsuccinate-derivatised starch using a spray-dryer and stored at two different temperatures. The shelf life of vitamin C was analysed and X-ray diffraction, scanning electronic microscopy and laser diffraction analyses were performed. Samples stored at 7 and 25 °C retained 77.1 and 71.5%, respectively, of vitamin C after 77 days of storage. Capsules had an average size of 12.5 μm and were presented in an amorphous form. n-Octenylsuccinate-derivatised starch showed to be an interesting material for the encapsulation of passion fruit juice, and spray-drying proved itself as an inexpensive alternative to freeze-drying, capable of retaining vitamin C during a long time of storage, and easy to be diluted in order to reconstitute the passion fruit juice for human consumption.     

乳酸发酵液电渗析过程中氨基酸的迁移现象

使用三室双极膜电渗析法处理乳酸发酵液时,杂质氨基酸的迁移会影响回收乳酸的纯度. 通过对乳酸发酵液电渗析过程中氨基酸迁移现象的研究,发现各种不同氨基酸的迁移速率主要受其初始浓度、pI值与料室pH值的差值、阴离子交换膜对其选择性及其自身电迁移率的影响. 根据此规律,建立了离子迁移速率计算模型,通过与实际过程比较,表明其可有效预测杂质氨基酸的迁移情况,估算特定体系达到预定收率时的纯度. 实验验证结果表明,氨基酸的迁移率为32.5%,与对照实验(82.6%)相比,降低率为60.7%. 通过调节氢渗漏控制料室pH值、提高阴膜对乳酸的专一选择性等可控制氨基酸向酸室迁移,以获取更高的乳酸纯度.     

Separation of phenylacetic acid, 6-aminopenicillanic acid and penicillin G with electrodialysis under constant current

The separation behavior of phenylacetic acid (PAA), 6-aminopenicillanic acid (6-APA) and penicillin-G (Pen-G) with electrodialysis under constant current was studied. The effects of ionic concentrations and current density on their separation behavior were investigated. The sorption of PAA, 6-APA and Pen-G and in the anion exchange membrane, and the variations of the applied voltage and current efficiencies with time during electrodialysis were also examined. It was found that the molecular size and the affinity toward the anion exchange membrane played a key role for the electrodialysis of PAA, 6-APA and Pen-G. Phenylacetic acid had the lowest affinity toward the membrane but the fastest transport rate. Penicillin-G had the highest affinity toward the membrane but the slowest transport rate. With the increase of Pen-G concentration, the concentration polarization of Pen-G in the vicinity of anion exchange membrane became very serious, which severely retarded the transport of PAA and 6-APA. Although the increase of current density accelerated the transport of PAA, 6-APA and Pen-G, more serious concentration polarization of Pen-G occurred and the separation ratio of PAA to 6-APA decreased.     

双极膜电渗析法制备1,5-戊二胺

1,5-戊二胺(C5H14N2)是生物法制备尼龙材料的重要原料,具有广泛应用前景。利用双极膜电渗析产碱技术可将盐溶液中的1,5-戊二胺盐转换为1,5-戊二胺,实现生物发酵液中1,5-戊二胺的无害化提取过程。本工作用1,5-戊二胺硫酸盐模拟生物发酵液的主要成分,探究了不同电流模式、电流密度、盐室初始浓度及杂质离子对1,5-戊二胺制备过程指标产生的影响,分析了双极膜在长时间运行后膜表面的损伤和污染情况。结果表明,料液中的硫酸根离子可以有效地被分离,在电流为3.6 A的恒流模式下,1,5-戊二胺回收率可达到97.5%以上;在电压为29 V的恒压模式下,1,5-戊二胺回收率可达到90%以上。高至3.45 kWh/kg双极膜在反复使用35次左右后,其阳离子交换层表面出现损伤的迹象,阴离子交换层表面黏附微量固体污染物。     

Comparative Studies on Electro-Membrane Processes for Recovery of Ascorbic Acid from its Sodium Salt

This article presents an efficient electro-membrane reactor with three compartments (EMR-3) for in situ ion substitution and recovery of ascorbic acid (ASH) from its sodium salt (ASNa). In situ ion substitution, separation, and recovery of ASH from ASNa were achieved by EMR–3 using the ion-exchange membranes (cation-exchange membranes: CEMs), based on the principle of electro-electrodialysis. Process performances of EMR–3 and electrodialysis (ED) were compared. Under optimum operating conditions for EMR–3 at 3.0 V cm^?1 applied voltage (after passage of 3.41 × 10³ Coulombs), current efficiency (CE), and energy consumption (W) were found to be 94.3% and 2.63 kWh kg^?1, respectively, corresponding to 95% recovery of ASH. While by ED, under the similar experimental conditions, CE and W were found to be 59.1% and 5.44 kWh kg^?1, respectively corresponding to 86.3% recovery of ASH. It was concluded that EMR–3 showed high CE, recovery, and low W, in comparison with ED under similar experimental conditions. Thus the proposed EMR–3 is an efficient alternate for producing ASH from ASNa in an by economical and environmentally-friendly manner. Also, the production of NaOH in cathode stream is a spinoff of EMR–3.     

电渗析技术在木糖醇酸水解法制备中的应用

木糖醇作为一种可作为甜味剂的糖醇具有广泛的应用前景。目前工业上酸水解法制备木糖醇的过程中需要一个脱除水解液中的残酸的工艺步骤。传统的残酸去除方法为饱和石灰水中和法,存在能耗高、消耗的化学试剂多、污染大等缺点。为实验木糖醇的清洁生产,本文采用自我组装的电渗析装置对木糖水解液中的残酸进行了选择性的去除,考察了操作电流对残酸去除及木糖得率的影响。结果表明,当操作电流为30 mA·cm^-2时,电渗析过程对残酸的去除率大于99%,其木糖的得率为84.9%,电渗析工艺处理木糖水解液的能耗为179 kW·h·t^-1,脱酸工序成本为每吨母液139元,具有良好的经济效益和环境效益。由此可见,电渗析工艺在木糖醇酸水解法制备过程中具有广泛的应用前景。     

Study on the Effectiveness of Simultaneous Recovery and Concentration of 1-Ethyl-3-methylimidazolium Chloride Ionic Liquid by Electrodialysis with Heterogeneous Ion-Exchange Membranes

Due to the extensive range of ionic liquids (ILs) used in industry, an efficient recovery method is needed. In this study, the effectiveness of a simultaneous concentration and recovery method was investigated for 1-ethyl-3-methylimidazolium chloride ([Emim]Cl), an IL that was recovered using electrodialysis (ED). The optimal operational parameters for electrodialytic recovery were determined empirically. The variables that were investigated included the concentration of IL, applied voltage, linear flow velocity and the diluate-to-concentrate volume ratio. The recovery of [Emim]Cl, the concentration degree, the [Emim]Cl flux across membranes, the current efficiency, as well as the energy consumption were determined. The results of the experiments confirmed that [Emim]Cl concentration and recovery can be achieved using ED. The highest ED efficiency was obtained when a 2 V electric potential per one membrane pair was applied, using a 2 cm/s linear flow velocity, and by adjusting to 0.2 M IL in the feed solution. By using ED, a 2.35-fold concentration of [Emim]Cl with a recovery of 90.4% could be achieved when the diluate-to-concentrate volume ratio was 2. On the other hand, a 3.35-fold concentration of [Emim]Cl with a recovery of 81.7% could be obtained when the diluate-to-concentrate volume ratio was increased to 5.