ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

MWCNTs/SnZrMoP nano-composite as Ba (II)-selective electrode and heterogeneous catalyst for esterification of primary alcohols

Rupinder Kaur, Sandeep Kaushal, and Prit Pal Singh

Guru Nanak Dev Polytechnic College, Ludhiana, India

E-mail: kaushalsandeep33@gmail.com

Received: 10 August 2020  Accepted: 9 November 2020

Abstract:

The present investigation covers the synthesis, characterization and applications of a novel nano-composite of multiwalled carbon nanotubes–tin zirconium molybdophosphate (MWCNTs–SnZrMoP) ion exchanger. The synthesized material was characterized by various instrumental techniques viz. Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), and thermogravimetric/ differential thermal analysis (TGA/DTA). The nano-composite exhibited an ion exchange capacity of 2.56 meq g⁻¹, which is higher than its inorganic counterpart SnZrMoP (1.95 meq g⁻¹). The distribution studies confirmed that the as-synthesized nano-composite was selective for barium ions. The nano-composite was employed to fabricate an ion-selective electrode which showed a sub-Nernstian response for barium ions in the concentration range 1 × 10⁻⁷ M—1 × 10⁻¹ M, with a response time of 11 s. The average slope of the calibration curve was observed to be 23.3 mV/decade with 1.78 × 10⁻⁸ M as limit of detection (LOD). The synthesized material was also used as a heterogeneous catalyst in esterification reactions of some primary alcohols due to its high mechanical, thermal and chemical stability. The esters produced were characterized by nuclear magnetic resonance (¹H-NMR) and FT-IR techniques.

Keywords: Nano-composite; MWCNTs/SnZrMoP; Ion-selective electrode; Esterification; Potentiometric titrations

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-020-01427-4

Chemical Papers 75 (6) 2379–2393 (2021)