Preparation of aminoalkyl celluloses and their adsorption and desorption of heavy metal ions

Abstract

SYNOPSISAminoalkyl celluloses ( AmACs) were prepared from 6-chlorodeoxycellulose and aliphatic diamines HzN ( CHz),NHz ( m = 2, 4, 6, 8). Their adsorption and desorption of divalent heavy metal ions such as Cu2+, Mn2+, Co2+, Ni2+ and their mixtures were also investigated in detail.Adsorption of metal ions on AmACs was remarkably affected by the pH of the solution, the metal ion and its initial concentration, and also the number of methylene units in the diamines. No adsorption of metal ions occurred on AmACs in strongly acidic solutions. However, metal ions were adsorbed rapidly on AmACs from weakly acidic solutions and the amount of adsorption increased with increasing pH. The effectiveness of AmACs as adsorbents decreased with increasing length of the methylene moiety, and AmAC from ethylenediamine ( m = 2 ) was most effective. The adsorption of metal ions on AmACs was in the order Cu2+ > Ni2+ > Co2+ > Mn2+. Accordingly, their behavior followed the Irving-Williams series and Cu2+ ions were preferentially adsorbed from solutions containing metal ion mixtures. The adsorbed ions were easily desorbed from the AmACs by stirring in 0.1 M HC1.

Synthesis and reduction of 2-nitroalkyl polysaccharide ethers

“…However, none of the routes to these are suitable for large scale synthesis. Modified polysaccharides with primary or secondary amino groups are expected to have interesting properties for a number of reasons: aminopolysaccharides have potential for the immobilization of enzymes (Guiseley & Yalpani, 1987;Zaborsky, 1974), as ion-exchange resins (Bullock & Guthrie, 1965), for drug targeting (Fuchs, 1993) and for complexation of heavy metals in polluted water (Nakamura, Amano, Saegua & Sato, 1992). The amino functionality, which can easily be converted into other functionalities, makes these compounds excellent precursors for a wide variety of other secondary polysaccharide derivatives.…”

Preparation of hydrazinodeoxycellulose and carboxyalkyl hydrazinodeoxycelluloses and their adsorption behavior toward heavy metal ions

“…proceeds homogeneously as observed in the reaction of CDC with diamines. 7 This different reactivity with CDC is attributed HDC scarcely adsorbed Cu 2/ ions in the strongly acidic pH range of 1-2, but the adsorption increased rapidly with decreasing acidity in the weakly acidic and neutral region.…”

“…ions including Cu 2/ , Mn 2/ , Co 2/ , and Ni 2/ from In the present study, we intended to prepare dilute aqueous solutions. 7 three types of nitrogen-containing cellulose derivAdsorption of metal ions on AmACs is remarkatives, hydrazinodeoxycellulose and carboxyalkyl ably affected by the pH of solution, the metal ions hydrazinodeoxycelluloses. The latter can form and their initial concentrations, and also the numchelates with metal ions.…”

Deoxycelluloses and related structures

“…A later study demonstrated that thiodeoxycelluloses and hydrazinodeoxycelluloses could also remove more than 99% of mercuric ion [75]. Crosslinked diaminodeoxycelluloses were also observed to adsorb and desorb other heavy metal ions such as Cu 2 , Mn 2 , Co 2 and Ni 2 [76]. The removal of trace elements and uranium in natural and sea water was observed with various deoxycelluloses such as dithiocarboxypiperazinylcellulose ammonium salt [77,78] and thiodeoxycellulose [79].…”