Degradation of acetaminophen in a photocatalytic (batch and continuous system) and photoelectrocatalytic process by application of faceted-TiO2

Abstract

In this study, anatase TiO2 rich in {0 0 1} (T-{0 0 1}), {1 0 1} (T-{1 0 1}) and {0 1 0} (T-{0 1 0}) facets were hydrothermally synthesized by a two-step reaction; the samples was utilized for the acetaminophen (ACE) degradation in an aqueous solution in the photocatalysis (batch and continuous system) and photoelectrocatalysis process. The characterization of the samples was performed by FE-SEM, XPS, UV–Vis and XRD. The photocatalytic performance of T-{0 0 1}, T-{1 0 1}, and T-{0 1 0} (for ACE phototdegradation) were evaluated and the results showed that T-{0 0 1} and T-{1 0 1} are more effective for ACE photocatalytic degradation. Photoluminescence (PL) spectra showed that separation efficiency order of photo-generated e−-h+ are {0 1 0} ~ {0 0 1} > {1 0 1}. Continuous flow membrane photoreactor (MPR) was used for photocatalytic degradation of ACE; the performance of MPR were studied at various hydraulic residence times (HRTs). The best performance of the MPR was observed at an HRT of 6.47 h. It was found that the transmembrane pressure (TMP) build-up was negligible at low flux, but a considerable increment was observed at the flux greater than 40 L/m2 h. However, it was also observed that periodic backwashing could be used for complete removal of the fouling. The photoelectrocatalytic degradation of ACE under UVC illumination was also investigated by synthesized samples; the results showed that T-{0 1 0} and T-{0 0 1} are more effective for photoelectrocatalytic degradation of ACE. The photo-generated current of the synthesized samples was also measured and the results showed that the T-{0 1 0} has the highest photocurrent.