New promising composite materials useful in the adsorption of Cu(II) in ethanol based on cellulose and cellulose acetate
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This work describes for the first time the synthesis and characterization of new promising materials based on cellulose (Cel) and cellulose acetate (Celac), previously modified with aluminum oxide (CelAl and CelacAl) and post functionalized with 1,4-diazabicyclo [2.2.2] octane-n-propyltrimethoxysilane chloride (SiDbCl2), resulting the chemically modified hybrid materials CelAl/SiDbCl2 and CelacAl/SiDbCl2. The materials have shown to be useful in the adsorption of CuCl2 from ethanol, presenting high effective adsorption capacity. In the adsorption process, the copper ions diffuse into the solid solution interface and are retained as anionic complexes CuCl 3 − or CuCl 4 2− . An expressive effective adsorption capacity tQ, as well as the stability constants β1 and β2, were found for both adsorbents: (a) CelAl/DbCl2: tQ = 0.33 × 10−3 mol g−1, log β1 = 4.23 (±0.04) and log β2 = 6.99 (±0.03); (b) CelacAl/DbCl2: tQ = 0.48 × 10−3 mol g−1, log β1 = 5.1 (±0.1) and log β2 = 8.3 (±0.1). Both adsorbent materials are potentially useful in the pre-concentration and further analysis of Cu(II) present in trace amounts in ethanol, extensively used as an automotive fuel in Brazil. Regeneration of the adsorbents requires a very simple procedure consisting in their immersion in aqueous solution which causes the immediate release of the Cu(OH2) n 2+ species to the solution phase.
KeywordsCellulose Cellulose acetate Anionic copper complexes Stability constants
YG is indebted to FAPESP and CNPq for financial support; NF, HAM and LTA are indebted to FAPESP for MSc and Pos Doc fellowships. Authors wish to acknowledge Prof. Carol H. Collins for manuscript revision.
- Arenas LT, Pinheiro AC, Ferreira JD, Livotto PR, Pereira VP, Gallas MR, Gushikem Y, Costa TMH, Benvenutti EV (2008) Anisotropic self-organization of hybrid silica based xerogels containing bridged positively charged 1,4 diazoniabicycle[2.2.2]octane chloride group. J Colloid Interface Sci 318:96–102CrossRefGoogle Scholar
- Castro GR, de Oliveira JD, Alcantara IL, Roldan PS, Padilha CCF, Prado AGS, Padilha PM (2007) Application of cellulose modified with p-aminobenzoic groups in preconcentration system for determination of Cu, Fe, Ni, and Zn in fuel ethanol samples by flame atomic absorption spectrometry. Sep Sci Technol 42:1325–1340CrossRefGoogle Scholar
- Chaffa S, Douadi T, Khan MA, Meullemeestre J, Schwing MJ, Vierling F (1991) Halogéno complexes de cuivre(II) en milieu éthanol anhydre. New J Chem 15:39–46Google Scholar
- Gushikem Y, Toledo EA (1999) Preparation of oxide coated cellulose fiber. Polymer, interfaces and emulsions. In: Esumi K (ed) Surfactant sciences series. Marcel Dekker, New York, pp 509–534Google Scholar
- Roldan PS, Alcantara IL, Castro GR, Rocha JC, Padilha CCF, Padilha PM (2003) Determination of Cu, Ni, and Zn in fuel ethanol by FAAS after enrichment in column packed with 2-aminothiazole-modified silica gel. Anal Bioanal Chem 375:574–577Google Scholar