Fundamentals and applications of the photocatalytic treatment for the removal of industrial organic pollutants and effects of operational parameters: A review (original) (raw)
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15 Páginas, 8 Figuras, 3 TablasIn the present research, an annular photocatalytic reactor system was designed and operated to quantify the degradation of a real case chemical company wastewater. The photocatalytic degradation process was analyzed and optimized varying some critical operating variables such as pH, catalyst (TiO2) loading, H2O2 concentration (oxidant agent) and light intensity to find the best criterion warranting a high level of degradation. It was demonstrated that a pH of 7.0 and an amount of 2.0 g/L ofTiO2 resulted in a cleanup allowable level for discharge to river. Furthermore, photo-degradation by H2O2/TiO2/UV process was much more efficient (97%) with respect to the processes carried out individually by H2O2/UV(92%) orTiO2/UV (89%). It is remarkable that the optimum concentration of H2O2 was 11.6mM, and increasing the intensity of light accelerated degradation reaction. Careful selection of industrial wastewater reflected the capability predicting the level of...
International Journal Of …, 2011
During the last few years, there has been a plethora of research and development in the area of solar photocatalysis. The aim is to understand the fundamental processes and enhance photocatalytic efficiencies especially for air, soil and water pollution control. Municipal waste water is limited by continual organic water pollutants and micro-organisms that are not removed by conventional mechanical and biological treatment. In this overview of the most recent paper, studies focused on the treatment of municipal wastewater (containing organic compounds) by photocatalysis and the effects of various parameters such as pH, light intensity, Advance oxidation method etc. have been studied It can be concluded that the photocatalysis process is suitable for the treatment of drinking water, municipal and industrial wastewater. Some studies on the economic analysis of photocatalytic systems are also included.
Case Studies in Chemical and Environmental Engineering, 2024
The presence of persistent organic compounds in wastewater poses significant challenges to both biotic community and natural environment, resulting in a severely adverse effect on the ecosystem. In view of the urgent scenarios, the removal of pollutants from wastewater effluent has a significant potential to restore ecological equilibrium and maintain the social value of sustainability. Among the various methods used for wastewater treatment, photocatalytic advanced oxidation processes have gained as a viable and promising alternative approach. The objective of this review paper is to provide a comprehensive exploration of the various photocatalytic materials used in wastewater treatment with potential scopes for future enhancements. Further, various factors affecting the removal of pollutants from wastewater are highlighted. In particular, the selection, design aspects and scaleup criteria of photocatalytic reactors could assist in the establishment of commercial scale process. This review stimulates research on the kinetic study in order to get a deeper understanding of the mechanisms involved in the formation of novel photo-catalyst materials. Thus, photo catalytic advanced oxidation process could become as a spectacular treatment method for wastewater.
Catalysts
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Technologica Acta, 2019
Due to the toxicity effects and endocrine disrupting properties of many organic compounds, their removal from water and wastewater has gained widespread global attention. This review summarizes photocata-lytic degradation of different organic molecules present in wastewaters. This is an overview of photocatalytic degradation with the goal of presenting the technique as an attractive and viable process unit. This process has great potential for replacing other conventional methods for treatment of wastewaters and can be used at the advanced treatment stage. Photocatalytic degradation techniques should be more used in wastewater treatment because with this technique it is possible to decrease contaminants to certain acceptable discharge limits. However, the technique is still not being utilised on an industrial scale. This is mainly due to focus of researchers to study singular contaminants such as alcohols, carboxylic acid, phenol and its derivate, chlorinated aromatic compounds, colours , active pharmaceutical ingredients, and different type of surface active agents. TiO 2 can be used as a photo-catalyst in water purification to degrade organic pollutants.
Journal of Chemical Technology & Biotechnology, 2020
The research in the heterogeneous photocatalysis to remove different type of pollutants in liquid phase notably increased in the last years. The main objectives of the researches dealing with photocatalysis were: i) to shift the photoactivity of catalysts in the visible light range or to increase the degradation rate; ii) the use of the artificial light sources (low pressure lamp, high pressure lamp, LEDs and optical fibers) and solar light; iii) photocatalysts recovering and deactivation; iv) photoreactor configuration; v) photodegradation of contaminants of emerging concern, iv) verification of induced effects from the photocatalytic treatment, such as the induction of bacterial resistance. Here, one of the main problems of practical application of photocatalysis, which is to develop a methodology for the photoreactors scale-up, is addressed considering the use of mathematical modeling. In this perspective, this mini review reports a literature exam of the main parameters that is important to take into account for the design and the developing of photoreactors for wastewater treatment, also through the use of computational fluid dynamics models (CFD).
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International Journal of Chemical Reactor Engineering, 2014
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The chemical complexity of organic contaminants (drugs, agrochemicals, and dyes) requires new, more advanced ways to remove them from water compared to the conventional treatment methods used. One such method is photocatalytic degradation. In this paper, the mechanism of degradation of harmful organic compounds using semiconductor materials with photocatalytically active properties in the presence of UV or visible radiation will be explained. Methods and selection of components for the preparation of the latest developed photocatalysts, their stability, as well as the percentage of organic contaminant removal will be discussed. The discussion will also cover the advantages and drawbacks of photocatalytic methods, as well as future research in this area.
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OALib, 2014
Occurrence of persistent organic compounds in industrial effluents and their efficient removal technique has emerged as a crucial problem to waste water treatment plants. This review aims to focus on the plight associated with the effluents from textile industry, agricultural and pharmaceutical effluents. The occurrence of dyes, pesticides and endocrine disrupting chemicals in aquatic ecosystems may cause chronic diseases, affect the human endocrine system and have appeared as crucial factor to consider for drinking and non-potable end uses of water. Extensive researches have been attempted to screen effective and safe method of contaminants removal by modifying conventional treatments as well as advanced processes by renowned authors. This paper aims to review different possible routes of effluent treatment emphasizing on complete mineralization of the targeted contaminants. With this purpose, a comprehensive review has been presented to deliver essential information about dealing with photocatalytic mineralization of pollutants.