Design of rotary photoreactor using nano Cu/TiO2 for degradation humic acid in outdoor visible light

Doping agents that can increase the activity of TiO2 photocatalys, namely copper (II)
or Cu2+ ions because copper is one of the abundant transition metal elements on earth and has
Cu2+ (0,68 Å) ion radius which is close to the radius Ti4+ that is (0,74 Å) so that it can be
incorporated in TiO2 crystals. Coping is done using the sol-gel method. The Cu concentration
used for drying was 5% and calcined at 4000C. the results obtained were then characterized by
XRD and obtained by the structure namely anatase, then the crystals were used to degrade humic
acid in external light and by using variations in rotation speed and length of time of irradiation.
The best reduction in absorbance was found at a rotation speed of 1500 rpm, which was 69,18
% degraded humic acids.