Development of novel photocatalyst-impregnated adsorbents by using graphitic carbon nitride for organic dye removal in water

Abstract

 Graphitic carbon nitride (CN) is a photocatalyst that is driven by visible light and easy to synthesize. In this study, we developed a novel environmentally friendly and easily solid-liquid separable photocatalyst-impregnated adsorbent (CS/CN) using CN and chitosan (CS), a biodegradable adsorbent. We evaluated the adsorption and degradation characteristics of CS/CN for two organic dyes, acid black 1 (AB1) and malachite green (MG), in water. In the dye decomposition experiment using photocatalyst alone, CN almost completely removed the dyes (removal rate of more than 94%) in 180 to 390 min under UV-visible light irradiation by a xenon lamp; in the dye adsorption and degradation experiments using CS/CN, both AB1 and MG, which were not able to be removed by chitosan adsorbent alone, were removed under light irradiation (removal rate of over 91%). Although there are issues to be addressed, such as improving the photocatalytic activity of CN, CN -impregnated adsorbents may be effective for removing various pollutants in water.