CATALYTIC REDUCTION OF 4-NITROPHENOL TO 4-AMINOPHENOL USING CHITOSAN AG-TIO2NANOCOMPOSITE AND ITS APPLICATIONS IN THE REMOVAL OF MALACHITE GREEN BY PHOTODEGRADATION TECHNIQUE

Abstract

A simple colloidal processing method was used to synthesize chitosan Ag-TiO2 nanocomposite and its use aimed at the catalytic reductionof 4-nitrophenol to 4-aminophenol in the presence of NaBH4 as reductant. The nanocomposite catalyst was characterized using differenttechnquies and revealed its better catalytic ability than pure TiO2. Since the nanocomposites are readily improved from the solution phasewithout centrifugation or filtration. The catalytic activity trials were examined by changing the catalyst dose, concentration of NaBH4,amount of nitrobenzene and temperature. The reduction reactions were affected by the temperature of reaction medium and the concentrationof NaBH4. The photodegradation conditions were optimized by changing different parameters such as irradiation time, dosage, pH andinitial dye concentration.