Study on the preparation and adsorption thermodynamics of chitosan microsphere resins

Abstract

The aim of this research is to study the thermodynamic behavior of resins of chitosan microspheres (RCM) in adsorbing Cu²⁺, so that the theoretical basis of the application of RCM to eliminate metal ions in wastewater or fruit and vegetable juice can be obtained. First, RCM were prepared from chitosan as a raw material by using reverse phase suspension cross-linking polymerization, and some physicochemical properties of RCM were characterized. Second, the adsorption behavior of Cu²⁺ onto RCM was investigated by the batch method. The results show that the diameter of the microspheres was relatively uniform and the surface of microspheres was compacted with pores. The physical properties of the RCM were as follows: water content 51.982%, skeletal density 1.212 g•cm^-3, pileup density 0.862 g•mL^-1, porosity was in 0.554 and crosslinking degree was in 13.581%. The saturated adsorption capacity of RCM for Cu²⁺ was 0.993 mmol•g^-1. At the same time, the results also indicated that the adsorption of RCM for Cu²⁺ followed the Langmuir isotherm equation: C_e/Q=11.614+ 1.0075C_e at 313 K and the adsorption appeared to be of the monomolecular type. The adsorption was found through thermodynamic study to be a spontaneous endothermic process of increased entropy. The adsorption potential decreased gradually as Cu²⁺ concentration increased at the same temperature and it increased as temperature increased at the same initial concentration of Cu²⁺.

Keywords

resins of chitosan microspheres / adsorption Cu²⁺ / isothermal curve / thermodynamics

References

[1] Rhazi M, Desbrières J, Tolaimate A, Rinaudo M, Vottero P, Alagui A, El Meray M. Influence of the nature of the metal ions on the complexation with chitosan. Application to the treatment of liquid waste.European Polymer Journal, 2002, 38: 1523-1530

[2] Sun S L, Wang A Q. Adsorption properties and mechanism of cross-linked carboxymethyl-chitosan resin with Zn (II) as template ion. Reactive & Functional Polymers, 2006, 66: 819-826

[3] Ramnani S P, Sabharwal S. Adsorption behavior of Cr (VI) onto radiation crosslinked chitosan and its possible application for the treatment of wastewater containing Cr (VI). Reactive & Functional Polymers, 2006, 66: 902-909

[4] Shan B T, Zhou A H, Liang S K, Wang X L. Composition and characteristics of a bioflocculant produced by a Sphingobacterium sp.. Periodical of Ocean University of China, 2006, 36(5): 804-808 (in Chinese)

[5] Wang Y D, Gao M C, She Z L, Gu Y Y. Study on the decolorization kinetics of reactive red K-2BP wastewater by spongy iron. Periodical of Ocean University of China, 2006, 36(suppl): 137-140 (in Chinese)

[6] Zhang Y Y, Ma Q M. Adsorbent prepared from modified chitosan derivatives and study of its adsorption behavior. Periodical of Ocean University of China, 2006, 36(suppl): 153-156 (in Chinese)

[7] Wang D F, Yu L N, Su L, Zhang Y W, Wang C H. Resins of chitosan - Ce⁴⁺ complexes application in apple juice production. Chinese Rare Earths, 2006, 27(1): 11-14 (in Chinese)

[8] Su L, Wang D F, Yu L N, Geng J, Li L, Sun J P. Application of chitosan/ Ce⁴⁺ particles in the production of pullucid fruit juice. Food and Fermentation Industries, 2006, 32(1): 141-143 (in Chinese)

[9] Yu L N, Wang D F, Li H Y, Su L, Wang J L. Hydrolysis activities of resins of complexes made from polysaccharides and Ce⁴⁺. Journal of Rare Earths, 2006, 24 (spec): 125-129 (in Chinese)

[10] Yu Y H, Sun Y, He B L. Preparation and characterization of crosslinked chitosan resin. Transactions of Tianjin University, 2000, 33(1): 113-117 (in Chinese)

[11] Wang D F, Yu L N, Su L, Sun L P. The preparation technology on one kind of multi-functional rare earth polysaccharide microspheres. Chinese invention patent (ZL 200510042228.8), 2005-03-25 (in Chinese)

[12] Kosaraju S L, D’ath L , Lawrence A. Preparation and characterisation of chitosan microspheres for antioxidant delivery. Carbohydrate Polymers, 2006, 64: 163-167

[13] Zong Z, Kimura Y, Takahashi M, Yamane H. Characterization of chemical and solid state structures of acylated chitosans. Polymer, 2000, 41: 899-906

[14] Tang W J, Wang C X, Chen D H. Kinetic studies on the pyrolysis of chitin and chitosan. Polymer Degradation and Stability, 2005, 87: 389-394

[15] Neto C G T, Giacometti J A, Job A E, Ferreira F C, Fonseca J L C, Pereira M R. Thermal analysis of chitosan based networks. Carbohydrate Polymers, 2005, 62: 97-103

[16] Fujiwara K, Ramesh A, Maki T, Hasegawa H, Ueda K. Adsorption of platinum (IV), palladium (II) and gold (III) from aqueous solutions onto L-lysine modified crosslinked chitosan resin. Journal of Hazardous Materials, 2006, 49: 1-12

[17] Ngah W S W, Fatinathan S. Chitosan flakes and chitosan-GLA beads for adsorption of p-nitrophenol in aqueous solution. Colloids and Surfaces A: Physicochem Eng Aspects, 2006, 277: 214–222

[18] Chang Y C, Chen D H. Preparation and adsorption properties of monodisperse chitosan-bound Fe3O4 magnetic nanoparticles for removal of Cu (II) ions. Journal of Colloid and Interface Science, 2005, 283: 446-451

[19] Guzman J, Saucedo I, Revilla J, Navarro R, Guibal E. Copper sorption by chitosan in the presence of citrate ions: influence of metal speciation on sorption mechanism and uptake capacities. International Journal of Biological Macromolecules, 2003, 33: 57-65

[20] Li N, Bai R. Copper adsorption on chitosan-cellulose hydrogel beads: behaviors and mechanisms. Separation and Purification Technology, 2005, 42: 237-247

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