Nano-TiO2-loaded activated carbon fiber composite for photodegradation of a textile dye

An activated carbon fiber (ASC) synthesized from silk cotton fiber had been converted into a photocatalyst by loading nano-titanium dioxide (TiO2) [in anatase and rutile form] onto ASC. This novel photocatalyst (ASC-TiO2) was found to be active in UV and visible region of electromagnetic spectrum, and tested for its effectiveness in the removal of organic pollutants from industrial wastewater and effluents. In this study, heterogeneous photocatalytic decomposition of methylene blue (MB)-predominantly a textile dyestuff, using the catalyst -ASC-TiO2 had been found to be effective owing to the decomposition of organic pollutants into various harmless simple compounds like CO2 and H2O. Further studies were also conducted to optimize the operating conditions of this treatment by keeping initial dye concentration, catalyst load, and pH values as the causative variables. The results indicated that the catalyst was effective in alkaline medium and enhanced photodegradation of MB by ASC-TiO2 was well explained by pseudo-first-order kinetics.