Removal of colour from landfill by solar photocatalytic

Abstract

This study was conducted to examine the percentage of colour removal using coagulation as pretreatment, followed by the effects of ZnO, pH, stirring time and solar photocatalytic as final treatment. The duration of photocatalytic reaction occurs after 30 min of exposure to sunlight at solar intensity of 0.13- 0.89 kW m-2 that is from 11:00-1: 00 p.m. The study showed that, pretreatment of leachate by coagulation at no pH adjustment, at its natural pH 8.68 with addition 10 g L-1 FeCl3 as coagulant can remove 67.2% colour. But, 35% colour removal can be obtained by coagulation at pH 5 with addition 1 g L-1 FeCl3. Using 1.0 g L-1 ZnO at pH 5 capable of removing 97% colour after 120 min of exposure. However, when lower amount of ZnO (0.2 g L-1) was used together with addition H2O2 (50 ml L-1) at pH 5, the removal of colour was 95.3%.