Control of malodorous gases emission from wet-end white water with hydrogen peroxide

White water is highly recycled in the papermaking process so that its quality is easily deteriorated, thus producing lots of malodorous gases that are extremely harmful to human health and the environment. In this paper, the effect of hydrogen peroxide (H2O2) on the control of malodorous gases released from white water was investigated. The results showed that the released amount of total volatile organic compounds (TVOC) decreased gradually with the increase of H2O2 dosage. Specifically, the TVOC emission reached the minimum as the H2O2 dosage was 1.5 mmol/L, and meanwhile, the hydrogen sulfide (H2S) and ammonia (NH3) were almost completely removed. It was also found that pH had little effect on the release of TVOC as H2O2 was added, but it evidently affect-ed the release of H2S and NH3. When the pH value of the white water was changed to 4.0 or 9.0, the emission of TVOC decreased slightly, while both H2S and NH3 were completely removed in both cases. The ferrous ions (Fe2+) and the copper ions (Cu2+) were found to promote the generation of hydroxyl radicals (HO•) out of H2O2, enhancing its inhibition on the release of malodorous gases from white water. The Fe2+/H2O2 system and Cu2+/H2O2 system exhibited similar efficiency in inhibiting the TVOC releasing, whereas the Cu2+/H2O2 system showed better perfor-mance in removing H2S and NH3.

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Free-radical generation by copper ions and hydrogen peroxide. Stimulation by Hepes buffer

Biochemical Journal ◽

10.1042/bj2540519 ◽

1988 ◽

Vol 254 (2) ◽

pp. 519-523 ◽

Cited By ~ 115

Author(s):

J A Simpson ◽

K H Cheeseman ◽

S E Smith ◽

R T Dean

Keyword(s):

Hydrogen Peroxide ◽

Free Radical ◽

Hydroxyl Radicals ◽

Copper Ions ◽

Free Radical Generation ◽

Hepes Buffer ◽

Radical Generation ◽

Deoxyribose Degradation ◽

H2o2 System

Hydroxyl radicals (OH.), generated by a phosphate-buffered Cu2+/H2O2 system, were detected by lucigenin-amplified chemiluminescence, deoxyribose degradation and benzoate hydroxylation. In each system the buffer, Hepes, was found to stimulate radical generation significantly. There are two main reasons for this effect: Hepes increases Cu2+ solubility in phosphate-buffered systems, and forms a complex with Cu2+ that is effective in generating OH. from H2O2. Pipes, a structurally similar buffer, and histidine, a known Cu2+ chelator, were found to have a similar effect. These data suggest that the crucial factor in such free-radical-generating systems is the availability of Cu2+, and that these actions of Hepes should be considered in the design of studies utilizing such systems.

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Stationary source emissions. Determination of total volatile organic compounds (TVOCs) in waste gases from non-combustion processes. Non-dispersive infrared analyser equipped with catalytic converter

10.3403/30207396 ◽

2015 ◽

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Catalytic Converter ◽

Total Volatile ◽

Stationary Source ◽

Volatile Organic ◽

Total Volatile Organic Compounds ◽

Combustion Processes

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Investigations of Museum Indoor Microclimate and Air Quality. Case Study from Romania

Atmosphere ◽

10.3390/atmos12020286 ◽

2021 ◽

Vol 12 (2) ◽

pp. 286

Author(s):

Dorina Camelia Ilieș ◽

Florin Marcu ◽

Tudor Caciora ◽

Liliana Indrie ◽

Alexandru Ilieș ◽

...

Keyword(s):

Air Quality ◽

Volatile Organic Compounds ◽

Organic Compounds ◽

Construction Materials ◽

International Standards ◽

Total Volatile ◽

Negative Effects ◽

Museum Exhibits ◽

Volatile Organic ◽

Total Volatile Organic Compounds

Poor air quality inside museums is one of the main causes influencing the state of conservation of exhibits. Even if they are mostly placed in a controlled environment because of their construction materials, the exhibits can be very vulnerable to the influence of the internal microclimate. As a consequence, museum exhibits must be protected from potential negative effects. In order to prevent and stop the process of damage of the exhibits, monitoring the main parameters of the microclimate (especially temperature, humidity, and brightness) and keeping them in strict values is extremely important. The present study refers to the investigations and analysis of air quality inside a museum, located in a heritage building, from Romania. The paper focuses on monitoring and analysing temperature of air and walls, relative humidity (RH), CO2, brightness and particulate matters (PM), formaldehyde (HCHO), and total volatile organic compounds (TVOC). The monitoring was carried out in the Summer–Autumn 2020 Campaign, in two different exhibition areas (first floor and basement) and the main warehouse where the exhibits are kept and restored. The analyses aimed both at highlighting the hazard induced by the poor air quality inside the museum that the exhibits face. The results show that this environment is potentially harmful to both exposed items and people. Therefore, the number of days in which the ideal conditions in terms of temperature and RH are met are quite few, the concentration of suspended particles, formaldehyde, and total volatile organic compounds often exceed the limit allowed by the international standards in force. The results represent the basis for the development and implementation of strategies for long-term conservation of exhibits and to ensure a clean environment for employees, restorers, and visitors.

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Killing of Bacillus Spores by Aqueous Dissolved Oxygen, Ascorbic Acid, and Copper Ions

Applied and Environmental Microbiology ◽

10.1128/aem.69.4.2245-2252.2003 ◽

2003 ◽

Vol 69 (4) ◽

pp. 2245-2252 ◽

Cited By ~ 60

Author(s):

J. B. Cross ◽

R. P. Currier ◽

D. J. Torraco ◽

L. A. Vanderberg ◽

G. L. Wagner ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Ascorbic Acid ◽

Dissolved Oxygen ◽

Hydroxyl Radicals ◽

Fenton Reaction ◽

Copper Ions ◽

Transition Metal Ions ◽

Fenton Reagent ◽

Bacillus Spores ◽

Modified Fenton

ABSTRACT An approach to decontamination of biological endospores is discussed. Specifically, the performance of an aqueous modified Fenton reagent is examined. A modified Fenton reagent formulation of cupric chloride, ascorbic acid, and sodium chloride is shown to be an effective sporicide under aerobic conditions. The traditional Fenton reaction involves the conversion of hydrogen peroxide to hydroxyl radical by aqueous ionic catalysts such as the transition metal ions. Our modified Fenton reaction involves the conversion of aqueous dissolved oxygen to hydrogen peroxide by an ionic catalyst (Cu2+) and then subsequent conversion to hydroxyl radicals. Results are given for the modified Fenton reagent deactivating spores of Bacillus globigii. A biocidal mechanism is proposed that is consistent with our experimental results and independently derived information found in the literature. This mechanism requires diffusion of relatively benign species into the interior of the spore, where dissolved O2 is then converted through a series of reactions which ultimately produce hydroxyl radicals that perform the killing action.

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