Removal of 1,4-Dioxane and Volatile Organic Compounds from Groundwater Using Ozone-Based Advanced Oxidation Process

Abstract In the photochemical UV-H2O2 advanced oxidation process, H2O2 absorbs UV light and is decomposed to form hydroxyl radicals (OH·), which are highly excited and reactive for electron-rich organic compounds and hence can degrade organic compounds. In the present work, the UV-H2O2 process was investigated to degrade ciprofloxacin (CIP), one of India's widely used antibiotics, from aqueous solutions using a batch type UV reactor having photon flux = 1.9 (± 0.1) ×10-4 Einstein L-1 min-1. The effects of UV irradiation time on CIP degradation were investigated for both UV and UV-H2O2 processes. It was found that about 75% degradation of CIP was achieved within 60 s with initial CIP concentration and peroxide concentration of 10 mg L-1 and 1 mol H2O2/ mol CIP, respectively, at pH of 7(±0.1) and fluence dose of 113 mJ cm-2. The experimental data were analyzed by the first-order kinetics model to find out the time- and fluence-based degradation rate constants. Under optimized experimental conditions (initial CIP concentration, pH and H2O2 dose of 10 mg L-1, 7(±0.1) and 1.0 mol H2O2 / mol CIP, respectively), the fluence-based pseudo-first-order rate constant for the UV and UV-H2O2 processes were determined to be 1.28(±0.0) ×10-4 and 1.20(±0.04) ×10-2 cm2 mJ-1 respectively. The quantum yields at various pH under direct UV were calculated. The impacts of different process parameters such as H2O2 concentration, solution pH, initial CIP concentration, and wastewater matrix on CIP degradation were also investigated in detail. CIP degradation was favorable in acidic conditions. Six degradation products of CIP were identified. Results clearly showed the potentiality of the UV-H2O2 process for the degradation of antibiotics in wastewater.

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Using Volatile Organic Compounds in Waste Streams as Fuel

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2018-0252 ◽

2019 ◽

Vol 17 (6) ◽

Cited By ~ 1

Author(s):

Doruk Dogu ◽

Hyuntae Sohn ◽

Shubho Bhattacharya ◽

Chris Cornelius ◽

Umit S. Ozkan

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Steam Reforming ◽

Oxidation Process ◽

Waste Streams ◽

Operational Costs ◽

Volatile Organic ◽

Exhaust Stream ◽

Thermal Oxidation Process ◽

Additional Fuel

Abstract To meet the environmental regulations, volatile organic compounds (VOC) in waste streams of various industries are thermally oxidized before being released to the atmosphere. This thermal oxidation process requires use of additional fuel and energy, has high operational costs and requires frequent maintenance. As an alternative, these VOCs can be considered as fuels themselves. Even without considering the energy used for the supplemental fuel such as natural gas, the enthalpy of the VOCs incinerated is not negligible. Hydrogen, a valuable energy carrier, can be produced from VOCs by reforming them. In this study, a system that can reform VOCs in the exhaust stream of paint finishing operations and use it to produce hydrogen that can be used in a fuel cell for power generation was designed. Steam reforming experiments were conducted on different VOCs using a 10 % Co/CeO2 catalyst. The effect of different functional groups and the chain length was examined. This study shows the potential of dilute VOCs in the waste stream of many industries if they can be recovered and used as a fuel effectively instead of being incinerated.

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Removal of Refractory Organic Compounds from Wastewater by Various Advanced Oxidation Process - A Review

Current Environmental Engineering ◽

10.2174/2212717806666181212125216 ◽

2019 ◽

Vol 6 (1) ◽

pp. 8-16 ◽

Cited By ~ 5

Author(s):

Manjari Srivastav ◽

Meenal Gupta ◽

Sushil K. Agrahari ◽

Pawan Detwal

Keyword(s):

Organic Compounds ◽

Conventional Treatment ◽

Advanced Oxidation Process ◽

Oxidation Process ◽

Oxygen Demand ◽

Ultra Violet ◽

Advanced Oxidation ◽

Complete Removal ◽

Pollutant Removal ◽

Treatment Technologies

Per capita average annual freshwater availability is gradually reduced due to increasing population, urbanization and affluent lifestyles. Hence, management of wastewater is of great concern. The wastewater from different industries can be treated by various conventional treatment methods but these conventional treatment technologies seem to be ineffective for the complete removal of pollutants especially refractory organic compounds that are not readily biodegradable in nature. Detergents, detergent additives, sequestering agents like EDTA, Pesticides, Polycyclic aromatic hydrocarbons, etc. are some of the recalcitrant organic compounds found in the wastewater. One of the treatment technologies for the removal of recalcitrant organic compounds is Advanced Oxidation Process (AOP). The production of hydroxyl free radical is the main mechanism for the AOP. AOP is a promising technology for the treatment of refractory organic compounds due to its low oxidation selectivity and high reactivity of the radical. Hydrogen peroxide (H2O2), Ozonation, Ultra-violet (UV) radiation, H2O2/UV process and Fenton’s reaction are extensively used for the removal of refractory organic compounds thus reducing Chemical Oxygen Demand (COD), Total Organic Carbon (TOC), phenolic compounds, dyes etc. to great extent. From the studies, we found that Fenton’s reagents appear to be most economically practical AOP systems for almost all industries with respect to high pollutant removal efficiency and it is also economical. From the energy point of view, the ozone based process proves to be more efficient but it is costlier than the Fenton’s process.

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A New Type of Reactor with a Combination of Surface Discharge and Advanced Oxidation Process in Air and its Applications

Journal of Advanced Oxidation Technologies ◽

10.1515/jaots-2006-0214 ◽

2006 ◽

Vol 9 (2) ◽

Author(s):

Mitsuaki Shimosaki ◽

Chobei Yamabe

Keyword(s):

Organic Compounds ◽

Applied Voltage ◽

Advanced Oxidation Process ◽

Oxidation Process ◽

Surface Discharge ◽

Wire Electrode ◽

Uv Emission ◽

Volatile Organic ◽

New Type ◽

Argon Mixture

AbstractA new type of reactor which is operated with a combination of surface discharge and UV radiation emitted by a lamp discharge is studied for both its fundamental characteristics and the treatment of volatile organic compounds (VOCs). The surface discharge occurs along the wire electrode which surrounds on the outer tube of reactor and generates ozone from the air. It seems that the UV emission has an effect on the initiation and uniformity of the surface discharge. The toluene treatment in oxygen or air and argon mixture gas was carried out and the decomposition of almost 100% was established at the applied voltage of 4 kV (peak to peak). The toluene in oxygen was converted into CO

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Volatile organic compounds (VOCs) control by combining bio-scrubber and ozone pretreatment

Global NEST Journal ◽

10.30955/gnj.003298 ◽

2020 ◽

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Removal Efficiency ◽

Advanced Oxidation Process ◽

Operating Conditions ◽

Gaseous Emissions ◽

Model Substance ◽

Volatile Organic ◽

Ozone Pretreatment ◽

Culture Growth

<p>Volatile Organic Compounds (VOCs) are toxic for the environment and human health and their tendency to readily volatilize in the atmosphere can lead to problems connected to odours annoyance. Conventional VOCs gaseous emissions treatments entail the application of chemical-physical processes, only promoting the transfer of the contaminants from gas to liquid and/or solid phases. Advanced Oxidation Process (AOPs) and biological processes, conversely, support the oxidation of the organic pollutants, promoting their conversion into harmless and odourless compounds. The integration of booth processes is suggested to increase treatability of VOC. The research presents the application of an innovative treatment system composed by an AOPs pretreatment coupled with a bio-scrubbing unit for the abatement of VOCs, with the aim to increase the removal efficiency. The evaluation of the performance of the proposed system is discussed with reference to the analysis carried out using toluene as model substance. Different operating conditions have been analyzed and investigated to optimize the removal efficiency. The results show that the ozonation applied as pretreatment to the biological process may promote an increase of the pollutant biodegradability along with synergic effects due to the absorption of the ozone derived compounds into the culture growth, resulting in a significant enhancement of removal performances respect to the conventional biotechnologies. A toluene removal efficiency up to 95% were obtained under the investigated conditions.</p>

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