Sulfonic acid type cation exchanger

Sulfonic acid-type cation exchanges showed the largest gi-factors and smallest hfs intervals of all the samples for Cu++ adsorbed. This is consistent with bond between the Cu++ and the adsorbents being largely ionic. 

For the vanadyl ion adsorbed on the various substrates examined, the g-factors were found constant, however, the hfs intervals varied, being largest on sulfonic acid-type cation exchangers, slightly smaller on charcoal and considerably smaller on an amine-type anion exchanger. 

Hexanedione containing a catalytic amount of Amberlyst 15, a sulfonic acid-type cation exchanger, heated at ca. 123 with distillation of the product at 77-90° while more dione is added to keep the volume approximately constant -> 2,5-di-methylfuran. Y 96%. - Similarly 1,5-Pentanediol -> tetrahydropyran. Y 94%. L. T. Scott and J. O. Naples, Synthesis 1973, 209. 

Rohm Haas XN1010 sulfonic acid type cation exchange resin, ground to 15 im particle size and put in the Ag" " form, 4.6 x 250 mm... 

Styrene-DVB copolymer beads are sulfonated to produce the most widely used strong-acid type cation-exchange resins. To make them, the copolymer precursor beads are dispersed in about 10 times their weight of concentrated sulfuric acid and heated slowly to 150°C. The sulfonic acid group is normally introduced into the para position. Though the reaction is very simple in principle, it involves delicate operations and close control of parameters in order to achieve beads of suitable structure and durability. A fully mono-sulfonated, polystyrene has a theoretical ion content of 5.1 equivalents/kg (dry) but many commercial resins have about 4.4-S.2 eq/kg. Amberlite IR-120, Dowex-50, Nalcite HCR, Permutit Q, Duolite C-20 and C-25, and Lewatit S-100 are resins of this type. 

On cation exchangers (sulfonic acid-type and carboxylic acid-type), a value of = 0.0089 cm. i was observed, corresponding to the hydrated Mn(H20)6++. The effect of axial symmetry (D 9 0) was observed as evidenced by a fine structure in the hyperfine lines. A value of D however was not determined. The EPR spectrum of Mn++ on an anion exchanger studied consisted of a single unresolved broad line. A smaller A value and larger... 

S. Tran, L. Dammak, C. Larchet and B. Auclair, Bi-ionic potential through a cation exchange membrane separating two electrolytes at different concentrations, Electro-chim. Acta, 1999, 44, 2515-2521 M. Tasaka and H. Sugioka, Dependence on salt concentration of bi-ionic potential across polystyrene sulfonic-acid-type membranes, J. Membr. Sci., 1988, 38, 27-37. 

Conventional cation-exchange resin such as AG 50W-X8, 8% cross-linked, 20-50 mesh, form (Bio-Rad), whose IE capacity is 5.1mEq/g is a sulfonic acid type. The structure of this resin is ... 

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