Adsorption of metal ions on novel 3-n-propyl (methylpyridinium) silsesquioxane chloride polymers surface: study of heterogeneous equilibrium at the solid-solution interface

Author(s)

Hérica A. Magosso ^[1] ; Natália Fattori ^[2] ; Yuriy V. Kholin ^[3] ; Yoshitaka Gushikem ^[4]

Affiliation

^[1] State University of Campinas. Institute of Chemistry - Brasil

^[2] State University of Campinas. Institute of Chemistry - Brasil

^[3] V.N. Karazin Kharkiv National University. Materials Chemistry Department - Ucrânia

^[4] State University of Campinas. Institute of Chemistry - Brasil

• Document type: Journal article
• Source: Journal of the Brazilian Chemical Society; v. 20, n. 4, p. 744-752, 2009-00-00.

Abstract

Polymers Si3Py+Cl- (A) and Si4Py+Cl- (B), 3-n-propyl (3-methylpyridinium) silsesquioxane and 3-n-propyl(4-methylpyridinium) silsesquioxane chlorides, respectively, were prepared by the sol-gel processing method. The ion exchange capacities (mmol g-1) were 0.90 and 0.81 for (A) and (B) respectively. Considering the reaction nSiPy+Cl-(s) + M2+(sln) + 2Cl-(sln) <IMG SRC="../img/a18setas.jpg" WIDTH=54 HEIGHT=15>(SiPy+)nMCl2+n n-(s), the values of the stepwise equilibrium constants obtained were: (A) CuII: logK(2)¹= 4.14(0.03), logK(2)²= 2.91(0.04); ZnII, logK(2)¹= 3.3(0.3), logK(2)²= 4.9(0.3); (B) CuII:logK(2)¹= 3.82(0.03), logK(2)²= 3.00(0.04); ZnII, logK(2)¹= 3.93(0.03), logK(2)²= 3.55(0.08), being K(2)¹ and K(2)² the equilibrium constants for adsorption of the species MCl4(2-) and MCl3-, respectively. For adsorption of ZnII on Si3Py+Cl-, K(2)² > K(2)¹, indicating positive cooperativity, i.e., the adsorption of MCl4(2-)enhances the adsorption of MCl3- species on the adsorbent surface. For the other cations, K(2)¹ > K(2)², indicating that adsorption of MCl4(2-)depresses the adsorption of MCl3-species, indicating negative cooperativity. <IMG SRC="../img/a18setas.jpg" WIDTH=54 HEIGHT=15> (AU)

• FAPESP's process: 00/11103-5 - Porous materials: preparation, properties and applications
• Grantee: Yoshitaka Gushikem
• Support Opportunities: Research Projects - Thematic Grants