Preparation, characterization and photocatalytic application of TiO2/Fe-ZSM-5 nanocomposite for the treatment of petroleum refinery wastewater: Optimization of process parameters by response surface methodology

Abstract

Photocatalytic degradation of organic contaminants from petroleum refinery wastewater under UV and sunlight was investigated by immobilizing nanosized TiO2 photocatalyst into the structure of as-synthesized Fe-ZSM-5 zeolite via sol-gel method. Pure phase of TiO2/Fe-ZSM-5 photocatalyst with specific surface area of 304.6 m(2) g(-1) and loaded TiO2 of 29.28% was successfully synthesized. Effects of various operational parameters on treatment process were investigated by use of Response Surface Methodology (RSM). Maximum reduction of 80% COD was achieved at pH of 4, a photocatalyst concentration of 2.1 g l(-1), temperature of 45 °C and UV exposure time of 240 min. Gas chromatography-mass demonstrated an apparent shift in molecular weight from a higher fraction to a lower fraction even under sunlight. It is expected that the prepared photocatalyst is able to use ultraviolet and visible light energy. Results indicated that removal of COD degradation did not decrease as the reuse cycle of photocatalyst increased. Moreover, the potential to use sunlight energy and the simplicity of operation make photocatalysis an attractive prospect in terms of petroleum refinery wastewater treatment.

Application of Heterogeneous Catalytic Ozonation for Refractory Organics in Wastewater

“…In this process, pH was a key operational parameter. Fe-based catalyst could possess a high activity at pH 6-9 [74][75][76]. On the contrary, at pH 6, many molecular ozone and little CO 3 2− existed in the weakly acidic solution, which led to better COD removal.…”

Optimization of photo-catalytic degradation of oil refinery wastewater using Box-Behnken design

“…The above photocatalytic reaction mechanism indicates that the degradation method is a clean technology and can be applied to the treatment of several wastewater applications where unwanted organics may exist [12]. Similar thoughts are shared by Ghasemi et al [13], where it was reported that some of the key benefits of using TiO 2 for PCD include the fact that no sludge formation occurs in the complete elimination of the contaminants. In addition, the use of the TiO 2 particles due to its ability to remove organics and in some cases inorganic pollutants, makes it appealing.…”

“…The PCD, as one of the emerging techniques, has some setbacks in operations which affects the TiO 2 reaction rate, hence requires an optimized condition to enhance effective degradation of the contaminants [8,11]. Some of the main factors that can affect the performance of PCD with TiO 2 include photo catalyst concentration, pH of the solution, reaction temperature, concentration of the pollutants, presence of inorganic ions, flow rate of air sparged, light intensity or wavelength and reaction time [13].…”

Preparation, Characterization, and Application of N,S-codoped TiO2/Montmorillonite Nanocomposite for the Photocatalytic Degradation of Ciprofl oxacin: Optimization by Response Surface Methodology

“…Eq. (1) was applied to explain the effect of independent variables in the second-order polynomial model: (1) where Y is the response (effi ciency removal), a 0 is the intercept value, a i , a ii , and a ij are regression coeffi cients, x i and x j are the independent variables, and e is the random error 9 . Analysis of variance was used to fi nd the interaction between the independent variables and the response.…”