Investigation of epoxy resin/nano-TiO2 composites in photocatalytic degradation of organics present in oil-produced water

Abstract

ABSTRACT Nano photocatalyst (TiO2) has been immobilised on a low-cost polymer (epoxy resin). Composite specimens are synthesised with varying amounts of TiO2 viz., 40, 50 and 60 weight%. The composite was used to study the degradation of organics present in oil-produced water (OPW). A series of batch experiments were conducted by varying the solution pH, stirring time, dosage, stirring speed and concentration of TiO2. Dissolved oxygen (DO), chemical oxygen demand (COD), turbidity, conductivity, and total dissolved solids (TDS) were evaluated to study the performance of the composites. The optimum conditions for the effective treatment of organics present in OPW were found to be pH 6, a stirring time of 60 minutes, 8 g per 100 mL of composite dosage, composite containing 60% TiO2 and stirring speed of 200 RPM. The maximum percentage removal efficiency of organics (COD) was achieved between 77% and 88% at optimum operating conditions depending upon the intensity of natural sunlight. The surface morphology of composites using scanning electron microscopy showed that photocatalyst particles aggregated to form particle clusters on the polymer matrix. Thermal gravimetric analysis (TGA) data revealed that incorporation of TiO2 into the polymer matrix improved the thermal stability of the composite. An FTIR spectrum confirmed the presence of TiO2 band peaks in the composite between wavenumbers 1000–1400 cm−1.