Correlating solvation-adsorption phenomena of some styrylpyridinium dyes on SDS modified silica surface in organic media

Abstract

Sodium dodecyl sulfate modified silica (SDSMS) surface has been used to study the adsorption of some cationic styrylpyridinium dyes from organic solvent media using ultraviolet-visible (UV-Vis) spectrophotometric technique. The modifications of silica surface and subsequent modification through adsorption of dye molecules on the surface have been characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), UV-Vis spectroscopy and zeta potential measurements. Kinetics of adsorption and consequent thermodynamic parameters have been studied and discussed. The isotherm modeling, choice of solvents from sedimentation analysis, and other common adsorption related parameters such as amount of adsorbent dosage, contact time, adsorption efficiencies have been reported. The influences of solvents and the substituents present on the dye molecules, on the rate of adsorption have been discussed. A pictorial model of adsorption process has been suggested based on the experimental results.

Graphical Abstract

Keywords:

• Adsorption
• isotherm
• silica
• surfactant
• sodium dodecyl sulfate
• solvatochromism

Declaration of interest statement

There is no conflict of interest and disclosures associated with the manuscript.

Acknowledgments

SD acknowledges the financial help provided by AICTE, New Delhi, through a RPS project and the TEQIP center at VSSUT, Burla, to establish and run the lab.

Additional information

Funding

All India Council for Technical Education.