Strongly acid cation resins

Eig. 5. Pressure drop as affected by resin type, flow rate, and temperature, where A, B, and C, correspond respectively to acryUc strong base anion exchanger (Amberlite IRA-458), styrenic strong base anion exchanger (Amberlite IRA-402), and styrenic strong acid cation exchanger (Amberlite IR-120), all at 4°C. D represents styrenic strong acid cation resin (Amberlite IR-120) at 50°C (14). To convert kg/(cm -m) to lb/(in. -ft), multiply by 4.33 to convert... 

Demineraliza tion of water is the removal of essentially all inorganic salts by ion exchange. In this process, strong acid cation resin in the hydrogen form converts dissolved salts into their corresponding acids, and strong base anion resin in the hydroxide form removes these acids. Demineralization produces water similar in quaHty to distillation at a lower cost for most fresh waters. 

Strong Acid Cation Resin Charged with H ... 

Resins containing these functional groups are generally available in one or more forms for example, strong acid cation resin is typically a sulfonated polystyrene type, available either in the hydrogen form (H+ ) or in the sodium form (Na+). The sodium form of this resin is used for water softening. 

Strong acid cation resins. These resins are highly ionized in both the acid (R—S03H) and salt (R—S03Na) form and behave like strong acids. They can convert a metal salt into the corresponding acid by the reaction... 

A more selective recovery of nickel from plating wastewater was described by Eom et al. [103].They used a column packed with strongly acidic cation resin through which over 99% nickel ion was removed. In this process, sulfuric acid was employed with a reagent in order to regenerate nickel ions from the resin adsorbed. Moreover, the nickel ions recovered by sulfuric acid were obtainable up to 120 g-Ni L 1 allowing reuse in the plating bath. 

Table 15. Absorption of the cryptand [2.2.1] and [2.2.2] with a strongly acidic cation resin (Ca -form, total Ca " -capacity...

Conversion or metathesis is a process in which salts of acids are converted to the corresponding free acids by reaction with the hydrogen form of a strong acid cation resin. One such example would be the conversion of calcium citrate to citric acid. 

Adsorbing lysine on ion exchange resin is probably the most vddely used industrial method of purifying lysine. The fermented broth is adjusted to pH 2.0 with hydrochloric acid and then passed through a column of strong acid cation resin in the NH/ form. Dilute aqueous ammonia may be used to elute the lysine from the resin. 

Shirato reported the concentration process for the antibiotic tubercidan produced from fermented rice grain using the microorganism, Streptomyces tubercidicus. Macroporous strong acid cation resin was used to concentrate the antibiotic from 700 pg/ml in the fermentation broth to 13 mg/ml when eluted with 0.25 N HCl. The yield of the antibiotic was about 83%. 

The strong acid cation exchange resins are made by the sulfonation of the matrix copolymer. Strong acid cation resins are characterized by their ability to exchange cations or split neutral salts. They will function throughout the entire pH range. 

Figure 15 shows the change in the ionic diffusion coefficients of tetra-alkylammonium ions in strong acid cation resins as a function of mean effective pore diameter of the resins.l As the pore diameter is increased, the penetrability of the resins with respect to the large ions also increased. 

Figure 11. Moisture content of strong acid cation resins as a function of divinylbenzene content.

The laboratory fermentation broth, which is similar to the commercial broth, contained 2.0 g/0.11 lysine, much smaller amounts of Ca", and other amino acids. The broth was passed through 500 ml of strong acid cation resin, Dowex HCR-S, in the NH/ form. The flow rate was 9 ml/min or 1.77 ml/min per cm of resin. It was determined that the resin capacity averaged 115 g of lysine-HCl per liter of resin. It may be noted that since the equivalent molecular weight of lysine-HCl is 109.6 g and the theoretical capacity of Dowex HCR-S is 2.0 meq/ml, the operating capacity is 52% of theoretical capacity. 

An important requirement for the successful operation of a mixed bed is the careful separation of the strong base anion resin from the strong acid cation resin by backwash fluidization. This is followed by contact of each type of resin with its respective regenerant in a manner which minimizes the... 

Strong-acid cation resins. Strongly acidic cation resins derive their functionality from the sulfonic acid groups. These strong-acid exchangers operate at any pH, split all salts, and require substantial amounts of regenerant. This is the resin of choice for almost all softening applications and as the first unit in a two-bed demineralizer or the cation component of a mixed bed. 

Reaction of a mixture of Pb(C2H5)4 and Pb(CH3)4 with a strong acidic cation resin for nonaqueous solutions of the type RSO3H gives a trialkyllead salt of the resin [121]. 

The resin used as a strong-acid cationic resin, crosslinked with divinylbenzene to form a polymer network, in the monovalent salt form. It is placed in a column alternately fed... 

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