Photocatalytic Degradation of Chlorinated Phenoxyacetic Acids by a New Buoyant Titania-Exfoliated Graphite Composite Photocatalyst

A new class of floating composite photocatalysts for water purification is introduced. The composite material is comprised of exfoliated graphite support, titania photocatalyst, and sol−gel-derived methyl silicate binder. The catalyst composition was optimized for the degradation of rhodamine B dye. The photodegradation performance of the optimized catalyst was compared with supported titania film and P-25 titania suspension for the degradation of chlorophenoxyacetic acids. The photodegradation of the coated catalyst was between 50% and 95% of the activity of supported photocatalyst film.