ABSTRACT:The retention process of the Cu(II) and Ni(II) cations from CuSO 4 and NiSO 4 aqueous solutions by eight acrylic ion exchangers was studied. Also, the elution process of these cations with 0.5 mol ⅐ L Ϫ1 HCl solution was analyzed. The quantitative retention and elution as well as the development aspects of the two processes were observed by the column method. Seven ion exchangers contained weak base, weak acid, and amphoteric functional groups, these being known as chelating agents. Also, an ion exchanger with carboxylic groups, as a model, was taken in this study. The experiments show that the ion exchangers can be divided in three types as follows: (a) bad chelating agents; (b) chelating ion exchangers with the limited efficiency; (c) ion exchangers with good chelating properties and a high application efficiency; especially, the ion exchanger with hydroxamic functional groups is considered in this class. Also, the experimental data prove that, both for Cu(II) and Ni(II) cations, the volume of the purified effluent is higher than the HCl volume needs for their complete elution. This fact means concentration of the metal cations in the liquid phase.
The paper extends previous studies on ultrahigh molecular weight synthetic polymers. The intrinsic viscosities and the viscosity constants of poly(isobutyl methacrylate) fractions were obtained by the methods of Huggins, Kraemer, Martin, Schulz‐Blaschke, and Fedors in CCl4 and C6H6 at 25°C. It was observed that the method of Fedors is not very sensitive to the possible errors appearing in estimating the relative viscosities in higher concentration domains. This method yields intrinsic viscosity values close to the mean values obtained from the other five methods and to the values calculated according to the averaging procedure suggested by Sakai. The transition concentrations separating the concentration domains (diluted‐semidiluted) and the Mark‐Houwink constants were obtained.
Acta Polymeric8 52 ((991) Nr. 5 230 IOAN, FLONDOR ct al.: Snlut,ion properties o f ultraliigh molecular wciglit polymers. 17 erkennen, ilaO die anionisch motlifizierten Fascrn (Probe 1) erwartungsgemiiB nicht mit dem ebenfalls negativ geladenen Quarz wechselwirken und die Extinktion im untersuchten Bereich gleich tlerjenigen der Nullprobe ist. Die kationische Funktionalisierung der Probe 2 bewirkt, dall die Extinktion i n hbhangigkeit vom Masseverhaltnis Quarz zu Fasern stark abnimmt. In den Bildern 2 und 3 ist der EinfluB der zunehmenden mechanischen Beanspruchung durch die Erhohung der Ruhrerdrehzahl dargestellt. WGhrend i m Bild 2 bei Quarz keine signifikante Drehzahlabhangigkeit feststellbar ist, steigt die Extinktion beiKaolin i m untersuchten Bereich stark a n (Bild 3). Die Ursache dafur ist sowohl in der zunehmenden Dispergierung des Kaolins zu suchen als auch in einer partiellen hblosung des Kaolins von der Faseroberfliiche. In beiden Fallen jedoch liegt die Extinktion bei Verwendung der Fasern erheblich unter derjenigen der Nullprobe.
The immobilization process of some biologically active proteins on acrylic ion exchange supports was studied. The cross-linking and swelling coefficient, as well as the molecular weight of the enzyme, were proved to influence the immobilization process. The kinetic data indicate mainly a binding process controlled by diffusion. The uptake coefficient values of different proteins ranged between 35.0 and 98.0%. The laboratory experiments per formed with some of the obtained enzymic preparation certify the preservation of the catalytic activity following the immobilization process.
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