AH∞control for optimizing the advanced oxidation processes—Case of a catalytic ozonation reactor

The degradation of sulfamethoxazole (SMX) by several advanced oxidation processes (AOPs) is carried out in the presence of different catalysts. The catalysts used consisted of carbon nanotubes (CNT), titanium dioxide (TiO2), a composite of carbon nanotubes and titanium dioxide (TiO2/CNT), and iron supported on carbon nanotubes (Fe/CNT). SMX removal was evaluated by catalytic ozonation, photocatalysis, catalytic oxidation with hydrogen peroxide, and combinations of these processes. The evolution of the SMX concentration during reaction time, the mineralization degree, the toxicity of the treated solution, and the formation of organic intermediates and ions were monitored. Ozonation catalyzed by Fe/CNT and CNT and photocatalytic ozonation in the presence of CNT presented the fastest degradation of SMX, whereas photocatalytic ozonation with CNT showed the best results in terms of organic matter removal (92% of total organic carbon (TOC) depletion). Total mineralization of the solution and almost complete reduction of toxicity was only achieved in the photocatalytic ozonation with H2O2 and Fe/CNT catalysts. The compound 3-amino-5-methylisoxazole was one of the first intermediates formed during SMX degradation. p-Benzoquinone was only formed in photocatalysis. Oxalic and oxamic acids were also detected and in most of the catalytic processes they appeared in small amounts. Ion concentrations increased with the reaction time.

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A study on ozonation and ozone based advanced oxidation processes for the removal of naphthenic acids from water: kinetic studies modelling and optimal control

10.32920/ryerson.14648601.v1 ◽

2021 ◽

Author(s):

Ali Kamel H. Al jibouri

Keyword(s):

Hydrogen Peroxide ◽

Optimal Control ◽

Advanced Oxidation Processes ◽

Operating Cost ◽

Advanced Oxidation ◽

Kinetic Studies ◽

Naphthenic Acids ◽

Catalytic Ozonation ◽

Oxidation Processes ◽

Outlet Stream

Industrial wastewater is one of the largest environmental challenges of this century. Most of these wastewaters contain non-biodegradable pollutants which need special treatment methods. Advanced oxidation processes (AOP’s), such as, ozonation, catalytic ozonation and ozone/ hydrogen peroxide have proved their effectiveness on the degradation of bio-recalcitrant pollutants. The main drawback in these processes is the high operating cost. The objective of this study was to develop innovative continuous ozonation and ozone based processes that can effectively degrade industrial non-biodegradable pollutants. Naphthenic acids (NAs) was used as the model pollutant in this study due to its importance as a major pollutant in oil and oil sands industries. The target was to convert bio-recalcitrant NAs into biodegradable substances with minimum consumption of ozone gas (operating cost). These processes can be followed by the biodegradation process to fully remove the rest of the pollutants. This research passed through several stages including screening of operating parameters, kinetic studies, and modeling, followed by optimal control of these processes. It was found that ozone concentration had the most significant effect on the NAs degradation compared to other parameters. The kinetics of direct and indirect (radical) ozonation of NAs were investigated and rate constants and activation energies of these reactions were determined. Catalytic ozonation of NAs was explored using alumina supported metal oxides and unsupported catalysts. Activated carbon was found to be the most effective catalyst. The addition of hydrogen peroxide into the ozonation systems significantly improved the removal of NAs compared with the ozonation only process. Models based on mass balance for the ozonation and ozone/ hydrogen peroxide processes were developed to predict the concentration profiles of reacting species. Optimal control policies of ozone/oxygen gas flow rate versus time were developed and validated to minimize NAs concentration in the liquid outlet stream from the continuous ozonation and ozone/ hydrogen peroxide processes. The experimental results demonstrated that the optimal control policies successfully minimized NAs concentration in the outlet stream. At the same time, ozone gas consumption was reduced to its minimum, i.e., just enough to minimize the concentration of NAs in the outlet stream.

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A study on ozonation and ozone based advanced oxidation processes for the removal of naphthenic acids from water: kinetic studies modelling and optimal control

10.32920/ryerson.14648601 ◽

2021 ◽

Author(s):

Ali Kamel H. Al jibouri

Keyword(s):

Hydrogen Peroxide ◽

Optimal Control ◽

Advanced Oxidation Processes ◽

Operating Cost ◽

Advanced Oxidation ◽

Kinetic Studies ◽

Naphthenic Acids ◽

Catalytic Ozonation ◽

Oxidation Processes ◽

Outlet Stream

Industrial wastewater is one of the largest environmental challenges of this century. Most of these wastewaters contain non-biodegradable pollutants which need special treatment methods. Advanced oxidation processes (AOP’s), such as, ozonation, catalytic ozonation and ozone/ hydrogen peroxide have proved their effectiveness on the degradation of bio-recalcitrant pollutants. The main drawback in these processes is the high operating cost. The objective of this study was to develop innovative continuous ozonation and ozone based processes that can effectively degrade industrial non-biodegradable pollutants. Naphthenic acids (NAs) was used as the model pollutant in this study due to its importance as a major pollutant in oil and oil sands industries. The target was to convert bio-recalcitrant NAs into biodegradable substances with minimum consumption of ozone gas (operating cost). These processes can be followed by the biodegradation process to fully remove the rest of the pollutants. This research passed through several stages including screening of operating parameters, kinetic studies, and modeling, followed by optimal control of these processes. It was found that ozone concentration had the most significant effect on the NAs degradation compared to other parameters. The kinetics of direct and indirect (radical) ozonation of NAs were investigated and rate constants and activation energies of these reactions were determined. Catalytic ozonation of NAs was explored using alumina supported metal oxides and unsupported catalysts. Activated carbon was found to be the most effective catalyst. The addition of hydrogen peroxide into the ozonation systems significantly improved the removal of NAs compared with the ozonation only process. Models based on mass balance for the ozonation and ozone/ hydrogen peroxide processes were developed to predict the concentration profiles of reacting species. Optimal control policies of ozone/oxygen gas flow rate versus time were developed and validated to minimize NAs concentration in the liquid outlet stream from the continuous ozonation and ozone/ hydrogen peroxide processes. The experimental results demonstrated that the optimal control policies successfully minimized NAs concentration in the outlet stream. At the same time, ozone gas consumption was reduced to its minimum, i.e., just enough to minimize the concentration of NAs in the outlet stream.

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Comparison of Advanced Oxidation Processes (AOPs) based on O3 and H2O2 for the Remediation of Real Wastewaters

Journal of Advanced Oxidation Technologies ◽

10.1515/jaots-2011-0214 ◽

2011 ◽

Vol 14 (2) ◽

Cited By ~ 1

Author(s):

Rui C. Martins ◽

Rosa M. Quinta-Ferreira

Keyword(s):

Hydrogen Peroxide ◽

Advanced Oxidation Processes ◽

Treatment Strategies ◽

Advanced Oxidation ◽

Catalytic Ozonation ◽

Oxidation Processes

AbstractSeveral treatment strategies based in ozone and hydrogen peroxide (single, catalytic ozonation over Mn-Ce-O and Fe

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Comparison of the Efficiency of Ultraviolet/Zinc Oxide (UV/ZnO) and Ozone/Zinc Oxide (O3/ZnO) Techniques as Advanced Oxidation Processes in the Removal of Trimethoprim from Aqueous Solutions

International Journal of Chemical Engineering ◽

10.1155/2021/9640918 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Moayede Taie ◽

Abdolmajid Fadaei ◽

Mehraban Sadeghi ◽

Sara Hemati ◽

Gashtasb Mardani

Keyword(s):

Zinc Oxide ◽

Reaction Time ◽

Aqueous Solutions ◽

Removal Efficiency ◽

Zno Nanoparticles ◽

Advanced Oxidation Processes ◽

Advanced Oxidation ◽

Catalytic Ozonation ◽

Continuous Reactor ◽

Oxidation Processes

Nowadays, advanced oxidation processes, particularly photocatalyst process and catalytic ozonation by ZnO nanoparticles, are the most efficient method of eliminating pharmaceuticals. The purpose of this study was to compare the efficiency of ultraviolet/zinc oxide (UV/ZnO) and ozone/zinc oxide (O3/ZnO) techniques as advanced oxidation processes in the removal of trimethoprim (TMP) from aqueous solutions. The process consisted of 0.6 g/L of ozone (O3), pH = 7.5 ± 0.5, TMP with a concentration of 0.5–5 mg/L, ZnO with a dose of 50–500 mg/L, 5–30 min reaction time, and 30–180 min contact time with UV radiation (6 W, 256 nm) in a continuous reactor. The high removal efficiency was achieved after 25 minutes when ZnO is used in 1 mg/L TMP under an operational condition at pH 7.5. When the concentration of the pollutant increased from 0.5 to 1, the average removal efficiency increased from 78% to 94%, and then, it remained almost constant. An increase in the reaction time from 5 to 25 minutes will cause the average elimination to increase from 84% to 94%. The results showed that the efficiency of O3/ZnO process in the removal of TMP was 94%, while the removal efficiency of UV/ZnO process was 91%. The findings exhibited that the kinetic study followed the second-order kinetics, both processes. With regard to the results, the photocatalyst process and catalytic ozonation by ZnO nanoparticles can make acceptable levels for an efficient posttreatment. Finally, this combined system is proven to be a technically effective method for treating antibiotic contaminants.

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Degradation of Low Concentrations of Formaldehyde in Sono Catalytic Ozonation Advanced Oxidation Processes using Zero-valent Iron

International Journal of Engineering ◽

10.5829/idosi.ije.2017.30.03c.06 ◽

2017 ◽

Vol 30 (3) ◽

Keyword(s):

Advanced Oxidation Processes ◽

Advanced Oxidation ◽

Catalytic Ozonation ◽

Zero Valent Iron ◽

Oxidation Processes ◽

Low Concentrations

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Paraben Compounds—Part II: An Overview of Advanced Oxidation Processes for Their Degradation

Applied Sciences ◽

10.3390/app11083556 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3556

Author(s):

João Lincho ◽

João Gomes ◽

Rui C. Martins

Keyword(s):

Wastewater Treatment ◽

Advanced Oxidation Processes ◽

Advanced Oxidation ◽

Catalytic Ozonation ◽

Contaminants Of Emerging Concern ◽

Ecotoxicological Assessment ◽

Oxidation Processes ◽

Endocrine Disrupting ◽

Pathogenic Agents ◽

By Products

Water scarcity represents a problem for billions of people and is expected to get worse in the future. To guarantee people’s water needs, the use of “first-hand water” or the reuse of wastewater must be done. Wastewater treatment and reuse are favorable for this purpose, since first-hand water is scarce and the economic needs for the exploration of this type of water are increasing. In wastewater treatment, it is important to remove contaminants of emerging concern, as well as pathogenic agents. Parabens are used in daily products as preservatives and are detected in different water sources. These compounds are related to different human health problems due to their endocrine-disrupting behavior, as well as several problems in animals. Thus, their removal from water streams is essential to achieve safe reusable water. Advanced Oxidation Processes (AOPs) are considered very promising technologies for wastewater treatment and can be used as alternatives or as complements of the conventional wastewater treatments that are inefficient in the removal of such contaminants. Different AOP technologies such as ozonation, catalytic ozonation, photocatalytic ozonation, Fenton’s, and photocatalysis, among others, have already been used for parabens abatement. This manuscript critically overviews several AOP technologies used in parabens abatement. These treatments were evaluated in terms of ecotoxicological assessment since the resulting by-products of parabens abatement can be more toxic than the parent compounds. The economic aspect was also analyzed to evaluate and compare the considered technologies.

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