Informatics Publishing Limited

B. Basavalingu ¹, K. Byrappa ¹, P. Madhusudan ¹

Affiliations
1 Department of studies in Geology, University of Mysore, Manasagangotri, Mysore - 570 006, IN

Abstract

The hydrothermal synthesis of diamond was carried out in the silicon carbide - organic compound system. The organic compounds were expected to dissociate in a closed system to generate C-O-H supercritical fluids, which are known for their high dissolving power and influence on the type of elemental carbon formation, especially in stabilizing the sp³-hybridized carbon. The SEM studies reveal that the bulk portions of the carbon formed are spherical/ovoid shaped particles and in a few cases nanosized crystallites. The micro Raman spectral studies of carbon crystallites reveal that they are having typical spectra of sp³-hybridization, thus clearly demonstrating the formation of nano-sized diamond crystallites under sub-natural conditions. In all the above investigations metal catalysts or the seeded diamond were not used, unlike in earlier attempts on the hydrothermal synthesis of diamond.

Keywords

Diamond, Hydrothermal Synthesis, Nanosized Crystals.

Full Text

     

C. P. Sajan ¹, B. Basavalingu ¹, A. Ananda ², K. Byrappa ¹

Affiliations
1 DOS in Earth Science, University of Mysore, Manasagangothri, Mysore - 570 006, IN
2 DOS in Chemistry, University of Mysore, Manasagangothri, Mysore - 570 006, IN

Abstract

The photocatalytic degradation of Indigo Caramine dye using commercial TiO₂ and fine grained natural rutile has been carried out. The commercial TiO₂ and natural rutile were characterized using powder X-ray diffraction (XRD) and Fourier transformed infra red spectroscopy (FTIR). The study on the photodegradation of Indigo Caramine dye using commercial TiO₂ and natural rutile were investigated both under Solar and UV irradiation. The degradation of Indigo Caramine dye was checked by the following parameters like Chemical Oxygen Demand (COD), %T, irradiation time and duration. In both cases using commercial TiO₂ and natural rutile, the COD of the dye solution was reduced from 288 mg/L to less than 20 mg/L, and similarly the %T was increased from 76% to 97% and the percentage decomposition upto 97% within the irradiation duration of 3.5 hrs. The preliminary results obtained on the photodegradation of Indigo Caramine dye are highly encouraging and further work is being carried out for the use of the natural rutile or anatase sources for the other organic decomposition and treatment of industrial effluents.

Keywords

Photocatalytic Degradation, Natural Rutile, Nanominerals, Indigo Caramine Dye.

Full Text