ADSORPTION OF POLLUTANT IONS FROM RESIDUAL AQUEOUS SOLUTIONS ONTO NANO-STRUCTURED CALCIUM SILICATE

作者：Valenzuela F^*; Basualto C; Sapag J; Ide V; Luis N; Narvaez N; Yanez S; Borrmann T

来源：Journal of the Chilean Chemical Society, 2013, 58(2): 1744-1749.

• Adsorption
• Pollutant ions
• Nanostructured calcium silicate
• Aqueous solutions

The sorption of contaminant ions existing in residual aqueous solutions onto nano-structured calcium silicate has been studied. The sorbent was prepared by chemical reaction between a soluble solution of sodium silicate and calcium hydroxide. X-ray diffraction analysis showed the amorphous character of the obtained calcium silicate, although patterns associated to wollastonite, CaSiO3, and larnyta-syn, Ca2SiO4 were detected. The particle mean size was approximate 0.5 to 1.0 mu m having an average BET surface area of 333.0 m(2)/g and a mean pore diameter variable between 15.8-23.6 nm. The nano-structured calcium silicates were contacted with industrial residual aqueous solutions containing, among others, Cu(II), Zn(II), Cd(II) and the anions PO43-, SO4= and CrO4=, being copper (II) and phosphate the ions that were most easily and quantitatively adsorbed. The results of equilibrium experiments showed that the Redlich-Peterson adsorption isotherm model explained the experimental results for some metal ions. The experimental kinetics followed a pseudo-second-order kinetics model for Cu(II) and Zn(II) sorption.

• 出版日期2013-6