Abstract
StruviteโK is the natural potassium equivalent to Struvite. StruviteโK crystals were grown by single diffusion gel growth technique in silica hydro gel medium. StruviteโK crystals with different morphologies having transparent to translucent diaphaneity were grown with different growth parameters. The phenomenon of Liesegang rings was also observed with some particular growth parameters. The crystals were characterized by powder XRD, FTโIR, TGA and dielectric study. The powder XRD results of StruviteโK confirmed the orthorhombic crystal structure. The FTโIR spectrum proved the presence of water of hydration, metal โ oxygen bond and P โ O bond. The TGA, DSC and DTA were carried out simultaneously. It was found that crystals started dehydrating and decomposing from 75 ยฐC and finally at 600 ยฐC temperature it became 64.14% of the original weight and remained almost constant up to the end of analysis. From the thermoโgravimetry, the numbers of the water molecules associated with the crystal were calculated and found to be 5. The kinetic and thermodynamic parameters of dehydration / decomposition process were calculated. The variation of dielectric constant with frequency of applied field was studied in the range from 400 Hz to 100 kHz, which exhibited the decreasing nature of the dielectric constant as frequency increased. The dielectric study showed that a.c. conductivity increased and consequently the a.c. resistivity decreased with the increase in frequency. (ยฉ 2011 WILEYโVCH Verlag GmbH & Co. KGaA, Weinheim)