Effects of Rice Husk Ash for Water Resilience Material (Hydrophobic Coating)

Abstract

The agricultural waste recycling has drawn a great contribution to the environmental and economic growth of a nation. The formulation of hydrophobic surface coating using agricultural waste for water resilience material may solve the durability issues. However, formulation of eco-friendly water resilience material is still a challenging issue. The long chain flouro-silane in the hydrophobic formulations are expansive and hazardous to the human health and environment. Thus, non-toxic silica source using rice husk ash was used in this study. Two different sources of rice husk ash were compared to know the  effect of hydrophobicity. Further testing on the surface wetting and water absorption were carried out on concrete surface for the water resilience performance. It was found that, the hydrophobicity was achieved at 142o water contact angle for 3 g RHA and 5 g calcium carbonate incorporated in the formulation. The coating was found to reduce the water absorption but not fully prevented it. The outcome of this study may be beneficial to fabricate hydrophobic coating using non-toxic and environmentally friendly silica source materials and later diversify its application in water resilience material.