Self-cleaning and photocatalytic properties of eco-friendly clay-based facing bricks from industrial and natural wastes

Abstract

In this study, self-cleaning and photocatalytic performance of clay-based facing bricks produced using two different wastes (red mud: RM, hazelnut shell: HS) under visible light by an organic pollutant, methylene blue (MB), were discussed. The results revealed that the incorporation of waste into the samples improved the photocatalytic activity for certain ratios and also provided the desired physical properties according to the relevant standards. In terms of self-cleaning performance, the best results were obtained from the samples containing 5% RM (RM5HS) and 10% RM (RM10HS) combined with 10% of HS by weight. While RM10HS with an apparent reaction rate of 2.99 × 10^-1 h^-1 achieved total removal efficiency of 89.74%, RM5HS with an apparent reaction rate of 2.82 × 10^-1 h^-1 was able to remove 91.21% of initial concentration of MB dye.

Keywords: Clay-based facing brick; Natural waste; Photocatalysis; Red mud; Self-cleaning.