학술논문

Kaolinite/TiO2/cobalt(II) Tetracarboxymetallophthalocyanine Nanocomposites as Heterogeneous Photocatalysts for Decomposition of Organic Pollutants Trimethoprim, Caffeine and Prometryn
Document Type
article
Source
Journal of the Brazilian Chemical Society. December 2019 30(12)
Subject
clay minerals
sol-gel
heterogeneous photocatalysis
Language
English
ISSN
0103-5053
Abstract
São Simão’s Brazilian kaolinite has been treated with titanium(IV) isopropoxide and cobalt(II) tetracarboxymetallophthalocyanine under different conditions (acidic or basic), leading, after drying at 100 ºC, to new titania-doped cobalt(II)-metallophthalocyanine/kaolinite solids. These solids were characterized by chemical analysis, powder X-ray diffraction, Fourier transform infrared spectroscopy, thermal analyses and nitrogen adsorption. No significant changes were observed by diffractometry, but the specific surface area depended of the synthetic route followed. The ability of these solids for photodegradation of trimethoprim, caffeine and prometryn was evaluated. The photodegradation was followed via mass spectrometry and UV-Vis absorption spectroscopy. The presence of photodegradation by-products was verified in all cases. All the photocatalysts showed high photodegradation rate against prometryn, trimethoprim and caffeine, the degradation efficiencies were 54, 30 and 90%, respectively, when using the heterogeneous photocatalysts. Comparison with commercial TiO2 (Degusa®) proved that the synthesized photocatalyst based on kaolinite present higher degradation rate than isolated titanium dioxide.