Open AccessRestoration of pretreated palm oil mill effluent using TiO2 based photocatalytic system: An optimization study
Author(s) -
Rab Nawaz,
Chong Fai Kait,
YeekChia Ho,
Mohamed Hasnain Isa,
Wen Huei Lim
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/736/4/042035
Subject(s) - pome , photocatalysis , anatase , response surface methodology , materials science , nuclear chemistry , central composite design , scanning electron microscope , visible spectrum , formic acid , chemical engineering , chemistry , pulp and paper industry , catalysis , chromatography , composite material , organic chemistry , optoelectronics , engineering
Phenolic compounds found in pretreated palm oil mill effluent (pre-POME) pose severe threat to aquatic ecosystem and human health due to their build-up in the environment and high toxicity. Thus, the removal of phenolic compounds from pre-POME is necessary to preserve environmental quality and protect human health. In this paper, the optimized degradation of phenolic compound, gallic acid (GA) from pre-POME under visible light assisted TiO 2 based photocatalysis is reported. TiO 2 nanoparticles (NPs) were synthesized by chemical precipitation technique followed by characterization with X-ray diffraction (XRD), diffuse reflectance UV-Vis spectroscopy (DR-UV-Vis) and field emission scanning electron microscopy (FESEM). The effect of process variables such as loading of TiO 2 and H 2 O 2 dose on the degradation of GA from pre-POME was investigated and optimized using response surface methodology (RSM) based on central composite design (CCD). Spherical shaped anatase phase TiO 2 NPs with size 45.47 nm and band gap (Eg) of 3.16 eV were obtained. The results demonstrated that both variables, TiO 2 loading and H 2 O 2 dosage showed positive effect on GA degradation. The highest removal of GA from pre-POME (71.20%), from 44.85 ppm of initial concentration was observed for the optimal TiO 2 loading of 0.88 g/L, H 2 O 2 dosage of 8.5 wt% and 2 h reaction under visible light irradiation. The use of H 2 O 2 combined with TiO 2 NPs indicated a great potential for the removal of GA, which has been pointed out as the major phenolic compounds in pre-POME.