Preparation of porous hybrid composite from calcium sand

Abstract

Koh Samed sand, which contains mostly calcium carbonate, was chosen to prepare a porous hybrid composite because it is cheap and non toxic. High molecular weight poly(vinyl alcohol) (PVA) was used as an organic phase, while boric acid was added as a crosslinking agent to improve mechanical properties. The resulting products were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Thermogravimetric analysis (TGA), and electron microscopy (SEM) and gas pycnometer. In order to use this hybrid porous material as a sensor to detect nickel ions (Ni2+) in waste water from batteries or nickel alloy manufacturers, 2% (w/w) Dimethylglyoxime (DMG) in ethanol was added as a detector. The formation of the Ni(DMG)2 complex from nickel (II) ions and DMG had a red-pink complex ion that was visible to the naked-eye. Spectrophotometric measurements were taken to test colorimetric response.