Sulfonic Acid Resin Research Articles

Selectivity of carboxylic ion-exchange resin for lanthanide ions

On a polymethacrylic acid ion-exchange resin (Amberlite IRC 50) the selectivity for lanthanide ions has been found to increase with decreasing ionic radius. This is the reverse of the order of selectivities found on sulphonic acid resins. Selectivity differences were also greater than on sulphonic acid resins. A polyacrylic acid resin (Amberlite XE 89) showed lower selectivities than the polymethacrylic acid resin.

Hydrolysis with silver resins: enhancement of hydrolysis rates of olefin esters by sulphonic acid resins containing silver ion

The rate of hydrolysis of an olefin ester by a sulphonic acid resin partially exchanged with Ag+ is compared with the rate of reaction of a saturated ester. A marked enhancement of the reaction rate of the olefinic ester is found. The results are interpreted in terms of the increased concentration of ester within the resin due to complexing of the Ag+ and the olefin.

Oleophilic Ion-Exchange Polymers. III. Equilibria and Chromatographic Separation of Organic Bases by Sulfonic Acid Resins in Nonaqueous Media1

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOleophilic Ion-Exchange Polymers. III. Equilibria and Chromatographic Separation of Organic Bases by Sulfonic Acid Resins in Nonaqueous Media1Andrew G. Tsuk and Harry P. GregorCite this: J. Am. Chem. Soc. 1965, 87, 24, 5538–5542Publication Date (Print):December 1, 1965Publication History Published online1 May 2002Published inissue 1 December 1965https://doi.org/10.1021/ja00952a003RIGHTS & PERMISSIONSArticle Views61Altmetric-Citations6LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (599 KB) Get e-Alerts Get e-Alerts

The N-terminus of myosin. I. Studies on N-acetyl peptides from a pronase digest of myosin.

The failure of fluorodinitrobenzene to reveal more than traces of N-terminal amino acid in rabbit myosin would be explained if this protein were acetylated at its N-terminus, a situation found in several other proteins. N-acetyl peptides have been sought for and found in a pronase digest of rabbit myosin. These acetyl peptides have been isolated by screening the digest through a sulphonic acid resin and have been separated from each other and from contaminating pyrrolidone carboxylic acid by chromatography on a strong base anion exchange resin (formate form) and subsequent chromatography on thin layers of silica or paper electrophoresis. They unexpectedly do not react with the Rydon-Smith reagent48. They have been identified as N-acetyl-Ser, N-acetyl-Ser-Ser-Asp-Ala-Asp, and a hexapeptide having the amino acid composition Ala, Asp2, Met, Ser2. The yields of peptides obtained indicate that there are at least two polypeptide chains per molecule of rabbit myosin of mol. wt. 600 000 having the N-terminal sequence N-acetyl-Ser-Ser-Asp-Ala-Asp, one at least of which has Met as the next residue.

Ion exchange studies in concentrated solutions—II: The alkaline earth cations with a sulphonic acid resin

A study has been made of the ion-exchange behaviour of Be, Ca, and Ba tracers in HClO 4, HCl, and HNO 3 solutions ranging from 0·1 to 10M in concentration on a sulphonic acid resin, Dowex-50W. In dilute acid solutions the normal elution order is found and the values of the distribution ratios decrease as expected from the mass-action effect. With concentrated solutions an increase in the value of the distribution ratio with increase in acid concentration occurs in certain cases, leading to an inversion in the elution order of the ions. These results are interpreted in terms of the competition among the water molecules, aqueous anions, and resin sulphonate anions for solvating the cations.

Self-Diffusion of Ions into Ion-Exchange Resins

A theoretical model for the self-diffusion of ions into an ion exchange resin is proposed, using the concept of an effective diffusion boundary layer with nonlinear concentration profile. The derived equation is of a general character and fit for wide concentration of the flowing solution. From it one can derive specialized equations already known for self-diffusion of ions in ion exchangers. To test the adequacy of the proposed model, series of experiments were performed on the self-diffusion of cesium ions into polystyrene sulfonic acid resin Dowex 50×8 from solutions of cesium and potassium chloride. The concentration of solutions was varied over a rather wide range. Several runs were made with different rates of the flow of the solution. Good fitting of experimental results with theoretically calculated curves over the whole experimental range indicates that the proposed model is adequate.

Measurement of thermodynamic functions for the sorption of amino acids on sulfonic acid resins in the hydrogen form

1. Sorption of amino acids in acidic solutions on sulfonic acid resins having a low value for ion exchange constants was determined by enthalpy factors. 2. Sorption of amino acids as zwitter-ionsis completely controlled by changing the entropy of the system. 3. A marked effect of sorbent structure on sorption selectivity of zwitter-ions was not observed.

Sorption of amides by cationic exchange resins from nonaqueous solvents

Separation of weakly basic acetanilide, N-methylacetanilide, and N- n-propylacetanilide could not be accomplished using a conventional sulfonic acid resin and various mixed eluants containing methanol and acetonitrile. The chromatograms showed elution bands that were broad and tailed badly. However, with a new macroreticular resin, some separations were obtained with the same nonaqueous eluants that had been used with the conventional resin. Although separation of acctanilide from the two N-substitutcd acetanilides was almost complete, the separation of the two N-substituted compounds was not. Acetamides were separated from acetanilides because the former were not retained by the resin when a 1 :9 methanol-acetonitrile eluant was used. The two important parameters which render these separations possible are probably solvation and hydrogen bonding around tile sulfonic acid group of the resin and resin matrix attraction. Methanol is a better solvating liquid than acetonitrile. In acetonitrile the amide probably associates through the carbonyl with the sulfonic acid; in methanol this association does not occur.

Optimum Ratio of Cations on Nuclear Sulfonic Acid Resin for Minimum Change in Composition of Resin-Treated Milk

For the purpose of developing a large-scale method for removing radiostrontium from milk, preliminary studies were carried out with Amberlite IR- 120. The optimum mole fraction of the major cations (Ca/sup 2+/, K/sup +/, Na/ sup +/, and Mg/sup on the strong sulfonic acid ion-exchange resin for minimum change in milk composition was determined by equilibrating the resin with milk at pH 5.4 and 6.6. The fraction of Ca on the resin increased with decreasing pH, whereas those of Na and K decreased. Mg was present in relatively small amounts, and it appeared to be little affected by pH. Relative affinities of ions for the resin were: Sr > Ca> Mg > K> Na. By using the milk-equilibrated mole fraction of the cations on the resin, and the apparent equilibrium constants involving the ions and the resin, mixed regenerating solutions of the chlorides of the 4 cations were prepared. The concentrations were adjusted so that the ratio of ions on the resin would be in equilibrium for milk at pH 6.6 and 5.4. Milk passed through columns of these resins showed little change in the cationic composition. The cationic composition of milk varies with breed of the animal, season ofmore » the year, and with other factors. Consequently, the milk-equilibrated mole fraction of cations placed on a resin will vary. (H.H.D.)« less

Activity coefficients of small ions in ion‐exchange resins

AbstractCrosslinked phenol sulfonic acid resins in the form of rods have been prepared. Anion uptake by these resins in equilibrium with aqueous solutions of NaCl, NaBr, Na2CO3, and Na3C6H5O7 at 30°C. in the concentration range 0.001–3.0N, their density, water content, and exchange capacity have been determined. From these data, activity coefficients of small ions in the resin phase have been calculated and compared with the values derived by the existing theories of Mackie and Meares, and Lazare et al. The agreement between the observed and calculated values is not satisfactory.

Enrichment of Lithium Isotopes by lon Exchange Chromatography.

Carboxylic acid resins and inorganic exchangers produced separation factors for lithium isotopes which were comparable to the factors observed for sulfonic acid resins. However, column efficiencies were not as good as those for sulfonic acid resins. The separation factors on phosphonous and phosphonic acid resins were an order of magnitude smaller than the factors for other exchangers. It is postulated that the degree of hydration of the lithium ion in the resin phase will determine the magnitude of the separation factor, and any mechanism that will dehydrate that ion will increase the factor.

Chromatographic isolations of pig and human melanocyte-stimulating hormones

Pig β-melanocyte stimulating hormone and a human melanocyte stimulating hormone have been isolated by chromatography on a sulphonic acid resin. Both require to have many of their basic groups discharged by a high pH, and the human melanocyte stimulating hormone also requires a hydrogen-bonding agent in the solution, if the partition of the active substances is not to be overwhelmingly in favour of the resin. Cations seem relatively ineffective in displacing these substances from the resin.

The separation of amino acids on ion-exchange resins by elution with water and aqueous ethanol

The elution pattern of amino acids from columns of ion-exchange resins in various forms has been studied. A sulfonic acid resin in the sodium form, a carboxylic acid resin in the acid form, and quaternary ammonium resin in the chloride form give the most useful separations. Water and 25% alcohol were the solvents employed. Acidic, basic, and neutral non-alpha amino acids were most highly purified. Partial resolution of neutral α-amino acids, β-alanine, and γ-aminobutyric acid and the basic amino acids were obtained on Dowex 1 in the chloride form. These procedures are characterized by relatively high capacity under mild conditions and have been useful in isolation of three nitrogen compounds from plants.

Chromatography of proteins of celite ion-exchange resins : I. Preparation of the resins and a study of the chromatographic behaviour of cytochrome c

1. Ion-exchange resins with a high capacity for protein were prepared by coating particles of the diatomaceous earth, Celite 545, with ion-exchange materials. Preparations of a carboxylic acid resin and a sulphonic acid resin are described. 2. A detailed study of the behaviour of cytochrome c on both resins was made under varying conditions of pH and cation concentration. The surprising feature of the results was the very high adsorption of cytochrome c on the sulphonic acid resin at pH values below 6. 3. A possible hypothesis to explain the high adsorption of proteins on cation-exchange resins in the region of pH 5 is outlined.

Theory and practice of resin‐catalyzed epoxidation

SummaryCommercial polystyrene sulfonic acid resins have been shown to be effective in catalyzing epoxidation of unsaturated fatty esters with hydrogen peroxide and acetic acid because they catalyze peracid formation but do not promote by‐product formation when used under proper conditions. Special resins with less cross‐linkage have been shown to yield mostly by‐products.Best catalyst life has been obtained with a special resin prepared with a low metal content.A continuous process based on the cascade principle has been demonstrated in the laboratory. The problem of resin re‐use for both continuous and batch processes can best be solved by using the optimum 10–15% based on oil weight and by replacing about 10% of the resin after each use.

Column Chromatography of Peptides and Proteins

The chapter presents a summary of recent experiments on the column chromatography of peptides and a description of the current status of chromatography as a method for purifying proteins. Columns of ion exchange resins have received particular attention because they were shown to yield quantitative results with amino acids, and hence would be expected to separate peptides quantitatively as well. In addition, such columns are not sensitive to the presence of neutral salts, and can thus be used directly for the analysis of physiological fluids or tissue extracts. When amino acids are chromatographed on sulfonated polystyrene resins, separations of peptides depend upon the affinity of the resin for both the ionic and the nonionic portions of the molecules. The great usefulness of paper chromatography for the separation of peptides has led to several attempts to extend the principles of liquid-liquid or liquid-gel system to columns packed with cellulose or starch. In the study of protein chromatography, many of the laboratory procedures employed are similar to those devised for experiments with amino acids and peptides. The actual protein concentrations can be calculated only if the ninhydrin color values per milligram or the extinction coefficients of the individual proteins are known. Successful chromatography requires that the proteins move down a column as discrete zones and give rise to relatively sharp and symmetrical peaks on an effluent curve. The chapter explores that sulfonic acid resins are employed in two quite different ways in the course of protein purifications.

The determination of the total electrolyte concentration of sugar products

A simple method for determining the total electrolyte content of impure sugar solutions is presented. The method is based on passing the dissolved tested sample through a column of a cation exchanger (hydrogen form of nuclear sulphonic acid resin) and titrating the resulting solution with standard alkali solution. A high coefficient of correlation was found between the proposed method and ash determination. An equation has been established by which the ash may be calculated with sufficient accuracy for practical purposes.

Studies on ion-exchange resins. V. Water vapor sorption

1. 1. Water vapor sorption studies on a series of ion-exchange resins are presented. The systems investigated include sulfonic acid cation-exchange resins of various degrees of cross-linking, a carboxylic acid resin, and a quaternary ammonium anion-exchange resin. 2. 2. Some direct calorimetric measurements of heats of sorption are presented. Free energies, heats of sorption, and entropies are calculated. 3. 3. The sorption behavior of sulfonic acid resins is compared with that of sulfuric acid. It is concluded that the sulfonic acid groups are osmotically inactive. For the sulfonic acid resins, variations in sorption with ionic state are discussed and interpreted. The partial molal volumes of the hydrated resin systems are studied. 4. 4. The behavior of the cross-linked polystyrene sulfonic acid resins is discussed from the point of view of simple, strong electrolytes in aqueous media. This interpretation is valid for the range 0–75% relative humidity; the influence of cross-linking makes itself felt above this point.

Neutrality regulation mechanisms in rats receiving sulfonic ion exchange resin.

SummaryRats receiving sulfonic acid resin respond by increasing their urinary output of acid phosphate and ammonia, but not in amounts sufficient to compensate for their fecal alkali loss. Those receiving moderate amounts of potassium resin show little change in acid-base balance, while those on high potassium resin intakes show a partially compensated alkali retention. The net fecal alkali loss amounts to 2.4 meq per g resin fed, but a large part of this represents increased phosphate absorption, presumably due to the binding of calcium and/or magnesium by the resin. There is suggestive evidence that some of the extra alkali appearing in the feces as a result of resin ingestion is not in direct combination with the resin, and this may have some bearing on the problem of neutrality regulation.

Physicochemical investigation of a cation exchange resin (amberlite IR100) I. Resin equilibria

1. 1. Equilibria between a sulfonic acid resin (Amberlite IR100) and salts of strong and weak acids are investigated. The limiting exchange (at high concentrations) is nearly the same for all alkali and alkaline earth chlorides and sulfates at low pH. It is greater for salts of weak acids, at higher pH, and increases in the order of decreasing acid dissociation constant. This suggests that the resin contains groups which are more weakly acid than -S0 3H, probably -COOH and phenolic -OH. The limiting exchange at pH = 2.0–2.5 is a few per cent below the strong acid equivalent as characterized by the sulfur content and the potentiometric titration curves. 2. 2. The law of mass action is applied to resin equilibria with salts of strong acids. The ratio of activity coefficients of the hydrogen ion to that of metal ion in the resin phase shows a marked variation with the experimental conditions. A number of possible causes for this is discussed.