Polypyrrole-TiO2 composite for removal of 4-chlorophenol and diclofenac

In this work, we successfully synthesized TiO2-polypyrrole (PPy) composite material via polymerization method using the sulfuric acid (H2SO4) as an oxidizing agent. Different characterization techniques, including electrostatic force microscopy, confirmed that TiO2 was intimately attached on PPy. The photocatalytic activity of PPy-TiO2 composite was studied experimentally for the conversion of diclofenac (DCF)– one of the most frequently detected pharmaceutical compounds in the aquatic environment – and 4-chlorophenol (4-CP) - largely used in the bleaching of cellulose pulp in the paper industry, as herbicide and pesticide - under simulated solar light irradiation at environmental conditions. This is the first time that a composite PPy-TiO2 was used as photocatalyst for the conversion of 4-CP. Results showed that the PPy-TiO2 was able to convert more than 90% of DCF and 40% of 4-CP in just 60 min, showing stability and efficiency over five consecutive cycles of reuse for both pollutants. The produced PPy-TiO2 showed higher photocatalytic efficiency compared to that of TiO2, thus proving itself to be a promising photocatalyst.