Ion Exchange Resin Treatment Research Articles

An intracytoplasmic injection of deionized bovine serum albumin immediately after somatic cell nuclear transfer enhances full-term development of cloned mouse embryos.

In mouse somatic cell nuclear transfer (SCNT), polyvinylpyrrolidone (PVP) is typically included in the nuclear donor injection medium. However, the cytotoxicity of PVP, which is injected into the cytoplasm of oocytes, has recently become a cause of concern. In the present study, we determined whether bovine serum albumin deionized with an ion-exchange resin treatment (d-BSA) was applicable to the nuclear donor injection medium in SCNT as an alternative to PVP. The results obtained showed that d-BSA introduced into the cytoplasm of an enucleated oocyte together with a donor nucleus significantly enhanced the rate of in vitro development of cloned embryos to the blastocyst stage compared with that of a conventional nuclear injection with PVP in SCNT. We also defined the enhancing effects of d-BSA on the blastocyst formation rate when d-BSA was injected into the cytoplasm of oocytes reconstructed using the fusion method with a hemagglutinating virus of Japan envelope before oocyte activation. Furthermore, immunofluorescence experiments revealed that the injected d-BSA increased the acetylation levels of histone H3 lysine 9 and histone H4 lysine 12 in cloned pronuclear (PN) and 2-cell embryos. The injection of d-BSA before oocyte activation also increased the production of cloned mouse offspring. These results suggested that intracytoplasmic injection of d-BSA into SCNT oocytes before oocyte activation was beneficial for enhancing the in vitro and in vivo development of mouse cloned embryos through epigenetic modifications to nuclear reprogramming.

Improvement of Saccharification and Fermentation by Removal of Endogenous Chemicals from Pretreated Lignocellulosic Biomass (1). Effect of Ion-Exchange Resin Treatment

The effects of removal of enzyme inhibitors on saccharification of lignocellulosic biomass and fermentation of their hydrolysate were examined with the aim of improving bioethanol production. Hydrothermal-mechanochemical treated woody powders lost their cell structures and lignin was widely and randomly distributed in treated woody powders. Enzymatic reaction resulted in the formation of many cracks and pores on the woody powder surface, and these cavities extended to the interior of woody powders. The concentrations of 3 kinds of phenolic enzyme inhibitors (gallic, tannic and trimesic acids) in the supernatant of the reaction mixture gradually increased during the enzymatic hydrolysis. Cracks and pores of hydrolyzed woody powders were probably routes of inhibitor release to the reaction mixture. Enzymatic saccharification was improved 1.4-fold by ion-exchange resin treatment after 24 hours of hydrolysis, and inhibition of cellulase activity was decreased by 60-95% compared to the control. Ethanol yield was improved 2.2-fold and lactic acid by 1.3-fold compared to corresponding yields using normal hydrolysates.

Conductivity measures coupled with treatment with ion-exchange resin for the assessment of sodium concentration in physiological fluids: analyses on artificial solutions

In humans, sodium is essential for the regulation of blood volume and pressure. During hemodialysis, sodium measurement is important to preserve the patient from hypo- or hyper-natremia Usually, sodium measurement is performed through laboratory equipment which is typically expensive, and requires manual intervention. We propose a new method, based on conductivity measurement after treatment of dialysate solution through ion-exchange resin. To test this method, we performed in vitro experiments. We prepared 40 ml sodium chloride (NaCl) samples at 280, 140, 70, 35, 17.5, 8.75, 4.375 mEq/l, and some "mixed samples", i.e., with added potassium chloride (KCl) at different concentrations (4.375–17.5 mEq/l), to simulate the confounding factors in a conductivity-based sodium measurement. We measured the conductivity of all samples. Afterwards, each sample was treated for 1 min with 1 g of Dowex G-26 resin, and conductivity measured again. On average, the difference ε in the conductivity between mixed samples and corresponding pure NaCl samples (at the same NaCl concentration) was 20.9%. With treatment with the resin, it was 9.9%, only. We conclude that ion-exchange resin treatment coupled with conductivity measures may be a possible simple approach for continuous and automatic sodium measurement during hemodialysis.

Sodium Concentration Measurement during Hemodialysis through Ion-Exchange Resin and Conductivity Measure Approach: In Vitro Experiments

Sodium measurement during hemodialysis treatment is important to preserve the patient from clinical events related to hypo- or hyper-natremia Usually, sodium measurement is performed through laboratory equipment which is typically expensive, and requires manual intervention. We propose a new method, based on conductivity measurement after treatment of dialysate solution through ion-exchange resin. To test this method, we performed in vitro experiments. We prepared 40 ml sodium chloride (NaCl) samples at 280, 140, 70, 35, 17.5, 8.75, 4.375 mEq/l, and some “mixed samples”, i.e., with added potassium chloride (KCl) at different concentrations (4.375-17.5 mEq/l), to simulate the confounding factors in a conductivity-based sodium measurement. We measured the conductivity of all samples. Afterwards, each sample was treated for 1 min with 1 g of Dowex G-26 resin, and conductivity was measured again. On average, the difference in the conductivity between mixed samples and corresponding pure NaCl samples (at the same NaCl concentration) was 20.9%. After treatment with the exchange resin, it was 14.7%, i.e., 42% lower. Similar experiments were performed with calcium chloride and magnesium chloride as confounding factors, with similar results. We also performed some experiments on actual dialysate solution during hemodialysis sessions in 15 patients, and found that the correlation between conductivity measures and sodium concentration improved after resin treatment (R=0.839 before treatment, R=0.924 after treatment, P<0.0001). We conclude that ion-exchange resin treatment coupled with conductivity measures may improve the measurement of sodium compared to conductivity measures alone, and may become a possible simple approach for continuous and automatic sodium measurement during hemodialysis.

Improvement of Ethanol Fermentation from Oligosaccharides in Spent Sulfite Liquor with Pichia stipitis by Combined Calcium Oxide and Ion Exchange Resin Treatments

The objective of this study was to develop an effective method for the removal of inhibitory compounds without decreasing oligosaccharides in spent sulfite liquor (SSL). The oligosaccharide fermentation was subsequently conducted by using Pichia stipitis, which is one of the feasible strains that can produce ethanol from oligosaccharides. The effect of inhibitory compounds on ethanol fermentation from cellobiose by P. stipitis was investigated. No ethanol was produced from cellobiose in the presence of more than 5 g/L of acetic acid. At 1 g/L of acetic acid, 2.6 g/L of ethanol was obtained after 40 h of fermentation. The removal of acetic acid in the SSL by the combined CaO and ion exchange resin treatments was also studied. The acetic acid concentration of softwood SSL was decreased from 5.2 to 0.9 g/L without decreasing oligosaccharides concentration by the combined method. Finally, the improvement of ethanol fermentation from oligosaccharides in the SSL by using the combined CaO and ion exchange resin treatments was studied. 1.3 g/L of ethanol was obtained from the SSL treated by the combined methods, while 6.5 g/L of total oligosaccharides were consumed. No ethanol was obtained from the untreated SSL.

コンブからうま味成分(L-グルタミン酸)を結晶化する簡単な実験方法

コンブからうま味成分(L-グルタミン酸)を結晶化する簡単な実験方法

Removal of Acetic Acid from Spent Sulfite Liquor Using Anion Exchange Resin for Effective Xylose Fermentation with Pichia stipitis

Acetic acid is one of the major inhibitors of spent sulfite liquor (SSL) fermentation for ethanol production. The objective of this study was to remove acetic acid from hardwood SSL using anion exchange resin in order to achieve effective fermentation with Pichia stipitis CBS6054. Lignosulfonate, as well as sulfate and sulfite ions in the SSL hindered the removal of acetic acid by anion exchange resins. CaO treatment was an effective method for removing these materials from SSL, which facilitated the removal of acetic acid in the subsequent ion exchange resin treatment. A two-stage strong base ion exchange resin (OH- form) treatment removed approximately 90% of the acetic acid from CaO-treated SSL, which decreased the acetic acid concentration to less than 1 g/L. The combined treatment of CaO and ion exchange resin treatments in a relatively short time achieved the selective removal of acetic acid from SSL and significantly increased the ethanol production from SSL.

Estimation of the surface sulfur content of cellulose nanocrystals prepared by sulfuric acid hydrolysis

The conditions required for the accurate measurement of the sulfur content of cellulose nanocrystals (CNCs) by conductometric titration are discussed. CNCs from sulfuric acid hydrolysis are electrostatically stabilized in aqueous suspension due to the introduction of charged sulfate ester groups onto the surface of the crystallites during reaction. The sulfur content thus largely reflects the surface charge of the crystals, and is crucial to the characterization and understanding of material properties. Conductometric titration is commonly used to quantify the sulfur content of CNCs, however, the exhaustive removal of free acid by dialysis and the necessity, type, quantity and duration of ion-exchange resin treatments are not always consistent. Here we explore the standard conditions of dialysis, ion-exchange, and the reproducibility of titration results. Extensive dialysis is found to be effective in the removal of free acid, but similar results are also achieved in shorter times and with less water using membrane ultrafiltration. It is also shown that the conditions of ion-exchange most commonly employed in the literature can lead to inaccurate sulfur contents. Finally, good agreement is obtained between the sulfur contents of different CNC batches prepared using the same hydrolysis conditions, and from titration and elemental analysis when thoroughly purified, well-dispersed samples, and appropriate resin conditions are used.

A combined process of activated carbon adsorption, ion exchange resin treatment and membrane concentration for recovery of dissolved organics in pre-hydrolysis liquor of the kraft-based dissolving pulp production process

To recover dissolved organics in pre-hydrolysis liquor (PHL) of the kraft-based dissolving pulp production process, a new combined process concept of sequential steps of activated carbon adsorption, ion exchange resin treatment, and membrane concentration, was proposed. The removal of lignin in the PHL was achieved in the activated carbon adsorption step, which also facilitates the subsequent operations, such as the membrane filtration and ion exchange resin treatment. The ion exchange resin treatment resulted in the removal/concentration of acetic acid, which opens the door for acetic acid recovery. The membrane filtration is to recover/concentrate the dissolved sugars. The combined process resulted in the production of PHL-based concentrate with relatively high concentration of hemicellulosic sugars, i.e., 22.13%.

Using UV Spectroscopy and Molecular Weight Determinations to Investigate the Effect of Various Water Treatment Processes on NOM Removal: Australian Case Study

AbstractNatural organic material (NOM) has been the focus of many studies because of its ability to compromise water treatment processes. This case study utilized ultraviolet (UV) spectroscopy and molecular weight distributions to investigate the impact of six water treatment processes (alum coagulation, magnetic ion exchange (MIEX) resin treatment, chlorination, ozonation, powdered activated carbon (PAC) adsorption, and biological sand filtration) on the removal of NOM from an Australia water source, Myponga Reservoir. Each of these processes displayed different effects on the concentration and character of NOM. The removal of dissolved organic carbon (DOC) and UV absorbance at 254 nm (UV254) by MIEX and the biological sand filter was shown to follow first-order kinetics with rate constants ranging from 9.0×10−8 s−1 (biological sand filter) to 6.3×10−5 s−1 (MIEX treatment). UV spectroscopic investigations showed the potential to predict the formation of disinfection by-products from chlorination with s...

Treatment of ion exchange resins used in nuclear power plants by super- and sub-critical water oxidation – A road to commercial plant from bench-scale facility

A super-critical water oxidation (SCWO) process has been developed to effectively reduce the quantities of waste ion exchange resins from the pressurized water reactors (PWR) in Korea. First of all, waste ion exchange resins were separated into cationic and anionic resins by a specific gravity difference in the fluidized bed. The separated resins were wet pulverized in a ball mill for 24h to make uniformly dispersed slurry in high concentration. The optimal decomposition conditions for waste cationic and anionic resins from thermal power plants were obtained in a bench-scale facility of reactor of 220mL volume. Then scale-up experiments were performed in a pilot plant with a 24L reactor. The optimal values of such parameters as process temperature, process pressure, residence time, amount of oxidant, and amount of additives (NaOH and CH3NO2) for decomposition were determined by the pilot plant. The optimal process condition on cationic ion exchange was found under the sub-critical condition. The process temperature for anionic ion exchange resins was lowered to 515°C. By using nitromethane as a denitrification agent, total-nitrogen (T-N) in the treated water was lowered as well as almost no NOx was emitted from the exhausted gases. Based on the production rate and the stored amount of waste resins in the nuclear power plant “A”, a commercial facility with process capacity of 150kg/h was designed in detail. In this paper, we present the procedure to scale-up from a bench-scale facility to a commercial plant and major check points in each stage.

Separation and treatment of ion-exchange resins used in cleaning systems of a research nuclear reactor

This study is based on experimental data from the elution of 60Co2+ ions with Na+ ions in mixed-bed columns packed with resins used in the cleaning system of a research nuclear reactor. The operational parameters for conditioning the resins were obtained by washing, separating cationic resins from anionic resins, and eluting radioactive ions from the cationic resins with a solution of 2N NaCl. The ion-exchange behavior of 60Co2+–Na+ was analyzed by measuring the variation of the activity or concentration of radioactive cobalt in a column as a function of the amount of saline solution required to desorb the radioactive cobalt from the column. The linear model was applied to obtain the constants that describe the 60Co desorption process.

Magnetic ion exchange treatment of stabilized landfill leachate

Stabilized landfill leachate is characterized by a high concentration of non-biodegradable organic matter, which is similar in chemistry to dissolved organic matter (DOM) in the natural aquatic environment. Magnetic ion exchange (MIEX) resin treatment is well-studied in drinking water for removal of DOM from natural waters. There are fewer studies evaluating MIEX treatment of waste waters, and there is no previous work evaluating MIEX treatment of landfill leachate. This work systematically evaluated MIEX treatment of stabilized landfill leachate and evaluated the results in the context of previous studies of MIEX treatment of natural and waste waters. Five leachates from four landfills were evaluated as a function of MIEX resin dose, mixing time, and regeneration efficiency. MIEX resin removed DOM from landfill leachate, even in the presence of a reported high background concentration of inorganic ions. MIEX resin that was exhausted with leachate DOM was effectively regenerated with a concentrated NaCl solution, and regenerated MIEX resin performed similarly to virgin resin. For a majority of the leachates, the removal trend for MIEX resin was color > UV-absorbing substances > dissolved organic carbon ≈ COD > total nitrogen. Finally, MIEX resin removed a wider range of DOM from leachate than coagulation. The most important contribution of this work is that MIEX treatment of leachate followed very similar trends as MIEX treatment of natural waters, which will allow previous MIEX data to be used to estimate the treatment efficiency of other waste waters.

Marine sediment pore‐water profiles of phosphate d18O using a refined micro‐extraction

Phosphorus cycling in the ocean is influenced by biological and geochemical processes that are reflected in the oxygen isotope signature of dissolved inorganic phosphate (Pi). Extending the Pi oxygen isotope record from the water column into the seabed is difficult due to low Pi concentrations and small amounts of marine porewaters available for analysis. We obtained porewater profiles of Pi oxygen isotopes using a refined protocol based on the original micro‐extraction designed by Colman (2002). This refined and customized method allows the conversion of ultra‐low quantities (0.5 – 1 µmol) of porewater Pi to silver phosphate (Ag3PO4) for routine analysis by mass spectrometry. A combination of magnesium hydroxide co‐precipitation with ion exchange resin treatment steps is used to remove dissolved organic matter, anions, and cations from the sample before precipitating Ag3PO4. Samples as low as 200 µg were analyzed in a continuous flow isotope ratio mass spectrometer setup. Tests with external and laboratory internal standards validated the preservation of the original phosphate oxygen isotope signature (δ18OP) during micro extraction. Porewater data on δ18OP has been obtained from two sediment cores of the Moroccan margin. The δ18OP values are in a range of +19.49 to +27.30‰. We apply a simple isotope mass balance model to disentangle processes contributing to benthic P cycling and find evidence for Pi regeneration outbalancing microbial demand in the upper sediment layers. This highlights the great potential of using δ18OP to study microbial processes in the subseafloor and at the sediment water interface.

Processing, analytical caracteristics and skin anti-ageing properties of a purified sea buckthorn extract

Sea buckthorn (Hippophae rhamnoides L. – Elaeagnaceae) is a spiny shrub native to Europe and Asia. The entire plant has been used for centuries in traditional medicine, but lately the interest has been focused on the berries, particularly for their nutritional value. They are rich in organic acids (mainly malic acid), carotenoids, phytosterols and flavonoïds. The berries are processed into 3 types of extracts: the pulp juice for the food market, pulp and seed CO2 extracts mainly for the cosmetic market. We focused on the potential use of sea buckthorn juice in cosmetic application, particularly for its organic acids. The juice commercialized for food products is difficult to use in cosmetics because of its odour and colour impacts on cosmetics products. In order to lessen this problem, we used ion exchange resins to purify the organic acids from a commercial sea buckthorn juice. The organic acids were analysed by HPLC – UV. After ion exchange resin treatment, the organic acids represent the majority of the soluble solids present in the juice. Malic acid concentration is about 3 times higher than in the previous commercial juice. Quinic acid is also present in important concentration, along with ascorbic acid. In addition to the organic acids, the treated juice still contains some flavonoïds. The anti-ageing activities of this organic acid rich sea buckthorn extract were demonstrated on dermal cells.

Comparison of treatment options for removal of recalcitrant dissolved organic matter from paper mill effluent

Recycling paper mill effluent by conventional water treatment is difficult due to the persistence of salt and recalcitrant organics. Elimination of dissolved organic matter (DOM) from paper mill effluent was studied using three treatment options, ion exchange resin (IER), granular activated carbon (GAC) and nanofiltration (NF). The removal efficiency was analysed based on hydrophobicity, molecular weight and fluorogenic origin of the DOM fractions. For IER, GAC and NF treatments, overall removal of dissolved organic carbon was 72%, 76% and 91%, respectively. Based on the hydrophobicity, all the three treatment methods majorly removed hydrophobic acid fractions (HPhoA). Further, IER acted on all fractions, 57% of HPhoA, 44% of transphilic acid and 18% of hydrophilics, substantiating that the removal is by both ion exchange and adsorption. Based on the molecular weight, IER and GAC treatments acted majorly on the high molecular weight fractions, whereas NF eliminated all molecular weight fractions. After GAC adsorption, some amount of humic hydrolysates and low molecular weight neutrals persisted in the effluent. After IER treatment, amount of low molecular weight compounds increased due to resin leaching. Qualitative analysis of fluorescence excitation emission matrices showed that the fulvic acid-like fluorophores were more recalcitrant among the various DOM fractions, considerable amount persisted after all the three treatment methods. Three treatment methods considerably differed in terms of removing different DOM fractions; however, a broad-spectrum process like NF would be needed to achieve the maximum elimination.

Removal of limonin bitterness by treatment of ion exchange and adsorbent resins

This study, the selective removal of limonin bitterness from Washington navel orange juice by batch adsorption to the Amberlite XAD-16HP and Dowex Optipore L285 was investigated and the determination of some compositional changes that occurred with orange juices debittering using adsorption resins were the primary focus. Amberlite XAD-16HP and Dowex Optipore L285 have been successfully used to reduce bitterness to acceptable levels in Washington navel orange juices. Amberlite XAD-16HP does not have any important negative effects on the quality characteristics of orange juices. However, Dowex Optipore L285 reduces the titratable acidity (TA) in the orange juices and so increases the content of soluble solids contents (SSC), pH value, and ratio accordingly.

Lowering NOM and DBP Levels by Managing Source Water Supplies: The New York City Approach

New York City has one of the most fascinating water systems in the world. Raw water is supplied from a network of 19 reservoirs and three controlled lakes in a 5,120 square kilometer watershed that extends 200 kilometers north and west of the City. About 90% of the supply, roughly 3.4 billion liters per day, comes from the Catskill/Delaware System, which consists of six source water and two balancing reservoirs. The only treatment provided is disinfection with free chlorine, corrosion control, and fluoridation – this is the largest unfiltered supply in the United States. While the quality of the raw water is extremely high, there are concerns about meeting the more stringent requirements of the United States Environmental Protection Agency's Stage 2 Disinfection Byproduct Regulations for haloacetic acids (HAAs). A comprehensive study was conducted by the New York City Department of Environmental Protection to evaluate a number of potential NOM/DBP control options including filtration, magnetic ion exchange resin treatment, converting to chloramines, and modifying reservoir operations. The purpose of this paper is to present the results of modifying reservoir operations with the goal of minimizing HAA levels in the City's water supply.

Magnetic ion exchange resin treatment for drinking water production

Italian drinking water treatment plants (DWTP) generally use chlorine-based chemicals to achieve the oxidation/disinfection phases of their treatment trains. The main problem related to the application of such disinfectants consists in the formation of disinfection by-products (DBPs) as a result of the reaction with organic substances in the water. Italian regulations set very strict limits for the maximum concentration of chlorine DBPs and, for many DWTPs, the compliance with such a regulation is difficult. Non-oxidative pre-treatments, able to remove organic substances from the water prior to chlorination, could be a suitable solution to overcome this problem. These treatments could increase the water quality, decrease the oxidant demand and, hence, reduce the formation of DBPs. This paper presents an experimental investigation of ion exchange processes for the dissolved organic carbon (DOC) removal by using MIEX® resin. The process was studied as a pre-treatment on raw river water. The DOC removal efficiency and the effects on downstream processes of the treatment train were evaluated.

Magnetic ion-exchange resin treatment: Impact of water type and resin use

Three raw waters of fundamentally different natural organic matter (NOM) character were treated by magnetic resin using a bench-scale method designed to mimic how the resin is used in continuous operation. Increasing water hydrophobicity resulted in reduced dissolved organic carbon (DOC) removal with removal of 56%, 33% and 25% for waters containing 21%, 50% and 75% hydrophobic NOM, respectively. Study of consecutive resin uses showed that the NOM in the hydrophobic water had high affinity for the resin shown by DOC removal of 65% after the first use of the resin. This dropped to 25% DOC removal after 15 consecutive resin uses. For the more hydrophilic waters, NOM removal remained consistent after each resin use. The hydrophobic sample contained higher MW NOM that was capable of blocking resin sites that prevented continual adsorption of organics on to the resin. The hydrophilic NOM containing a large proportion of hydrophilic acids was consistently removed to around 60%. The water containing algogenic-derived NOM was poorly removed by magnetic resin. Subsequent coagulation showed higher removal with increasing hydrophobicity.