Removal of N-Methyl-2-pyrrolidone by Photocatalytic Degradation in a Batch Reactor

Abstract

Photocatalytic degradation of N-methyl-2-pyrrolidone (NMP) was investigated in an aerated UV/TiO2 batch system. The effects of TiO2 photocatalyst loading, temperature, pH, initial concentration, and the type of gas phase on the reaction rate were ascertained, and the optimum conditions for the maximum degradation rate were determined. The results showed that photocatalytic degradation of NMP is strongly influenced by these parameters. The optimum TiO2 loading, which provides enough surface area for reaction without irradiation loss due to scattering of UV light, was found to be 0.1 wt %. It was revealed that due to bilateral effect of temperature on the process, the maximum oxidation rate (0.22 min–1) is obtained at 45 °C. The highest photodegradation reaction rate is obtained in neutral or slightly acidic condition rather than in extreme acidic or alkaline range. The pseudo-first-order reaction rate expression based on Langmuir–Hinshelwood model can reasonably simulate the photocatalytic degradation process. The optimum values for TiO2 photocatalyst loading, temperature, and pH were confirmed by economic factor analysis based on electrical energy consumption.

Synthesis and photocatalytic activity of TiO2 nanowires in the degradation of p-aminobenzoic acid: A comparative study with a commercial catalyst

“…When the TiO 2 NWs loading is greater than 1.0 gL -1 the photodegradation decreases due to system saturation, increasing the probability of interaction between catalyst particles. Also at higher catalyst loading a light screening effect may cause a dispersion of incident radiation and therefore decreasing the photocatalytic efficiency (Ji et al 2013a, Zolfaghari et al 2011. When the experiments are carried out with P25 a continuous improvement in the photocatalytic degradation of PABA up to 97% is observed.…”

Solar-light induced photodecolorization of water soluble azo-azomethine dye: influence of operational parameters and nanophotocatalysts

“…Among the commonly applied semiconductors, TiO 2 and ZnO with 3.42-3.54 and 3.37 eV band gaps, respectively, have received the greatest interest [18,19]. TiO 2 is found to be the most active photocatalyst under the photon energy of 300 nm < λ < 390 nm [20]. Moreover, good chemical durability and long-term photostability, low toxicity and inexpensive cost of TiO 2 have advanced its wide application in photocatalytic processes [21][22][23].…”

Mineralization of N‐Methyl‐2‐Pyrrolidone by UV‐Assisted Advanced Fenton Process in a Three‐Phase Fluidized Bed Reactor

“…Advanced oxidation processes (AOPs) have been applied for the destruction of recalcitrant pollutants with an aim to either completely mineralize the contaminants or to convert them into less harmful or shorter‐chain compounds which are biodegradable . The hydroxyl radicals ( • OH) generated in AOPs are highly active oxidants with a standard reduction potential of 2.8 V to non‐selectively degrade many contaminants .…”

“…[1][2][3][4] Advanced oxidation processes (AOPs) have been applied for the destruction of recalcitrant pollutants with an aim to either completely mineralize the contaminants or to convert them into less harmful or shorterchain compounds which are biodegradable. [1,[5][6][7][8] The hydroxyl radicals ( • OH) generated in AOPs are highly active oxidants with a standard reduction potential of 2.8 V to non-selectively degrade many contaminants. [9][10][11] Some of the AOPs include cavitation (acoustic and hydrodynamic), photocatalytic oxidation and Fenton chemistry, operated either individually or in combination.…”